add custom mouse event test

this was already updated, but subsequent PR (by me) accidentally reve…

.github/actions/install/action.yml

@@ -5,7 +5,7 @@ inputs:
   zig:
     description: 'Zig version to install'
     required: false
-    default: '0.14.1'
+    default: '0.15.1'
   arch:
     description: 'CPU arch used to select the v8 lib'
     required: false
@@ -17,7 +17,7 @@ inputs:
   zig-v8:
     description: 'zig v8 version to install'
     required: false
-    default: 'v0.1.24'
+    default: 'v0.1.28'
   v8:
     description: 'v8 version to install'
     required: false

.github/workflows/build.yml

@@ -60,7 +60,7 @@ jobs:
       ARCH: aarch64
       OS: linux
 
-    runs-on: ubuntu-24.04-arm
+    runs-on: ubuntu-22.04-arm
     timeout-minutes: 15
 
     steps:
@@ -76,7 +76,7 @@ jobs:
           arch: ${{env.ARCH}}
 
       - name: zig build
-        run: zig build --release=safe -Doptimize=ReleaseSafe -Dgit_commit=$(git rev-parse --short ${{ github.sha }})
+        run: zig build --release=safe -Doptimize=ReleaseSafe -Dcpu=generic -Dgit_commit=$(git rev-parse --short ${{ github.sha }})
 
       - name: Rename binary
         run: mv zig-out/bin/lightpanda lightpanda-${{ env.ARCH }}-${{ env.OS }}
@@ -98,7 +98,9 @@ jobs:
       ARCH: aarch64
       OS: macos
 
-    runs-on: macos-latest
+    # macos-14 runs on arm CPU. see
+    # https://github.com/actions/runner-images?tab=readme-ov-file
+    runs-on: macos-14
     timeout-minutes: 15
 
     steps:
@@ -136,6 +138,11 @@ jobs:
       ARCH: x86_64
       OS: macos
 
+    # macos-13 runs on x86 CPU. see
+    # https://github.com/actions/runner-images?tab=readme-ov-file
+    # If we want to build for macos-14 or superior, we need to switch to
+    # macos-14-large.
+    # No need for now, but maybe we will need it in the short term.
     runs-on: macos-13
     timeout-minutes: 15
 

.github/workflows/e2e-test.yml

@@ -45,6 +45,9 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 15
 
+    # Don't run the CI with draft PR.
+    if: github.event.pull_request.draft == false
+
     steps:
       - uses: actions/checkout@v4
         with:
@@ -65,56 +68,6 @@ jobs:
             zig-out/bin/lightpanda
           retention-days: 1
 
-  puppeteer-perf:
-    name: puppeteer-perf
-    needs: zig-build-release
-
-    env:
-      MAX_MEMORY: 30000
-      MAX_AVG_DURATION: 24
-      LIGHTPANDA_DISABLE_TELEMETRY: true
-
-    runs-on: ubuntu-latest
-    timeout-minutes: 15
-
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          repository: 'lightpanda-io/demo'
-          fetch-depth: 0
-
-      - run: npm install
-
-      - name: download artifact
-        uses: actions/download-artifact@v4
-        with:
-          name: lightpanda-build-release
-
-      - run: chmod a+x ./lightpanda
-
-      - name: run puppeteer
-        run: |
-          python3 -m http.server 1234 -d ./public & echo $! > PYTHON.pid
-          ./lightpanda serve & echo $! > LPD.pid
-          RUNS=100 npm run bench-puppeteer-cdp > puppeteer.out || exit 1
-          cat /proc/`cat LPD.pid`/status |grep VmHWM|grep -oP '\d+' > LPD.VmHWM
-          kill `cat LPD.pid` `cat PYTHON.pid`
-
-      - name: puppeteer result
-        run: cat puppeteer.out
-
-      - name: memory regression
-        run: |
-          export LPD_VmHWM=`cat LPD.VmHWM`
-          echo "Peak resident set size: $LPD_VmHWM"
-          test "$LPD_VmHWM" -le "$MAX_MEMORY"
-
-      - name: duration regression
-        run: |
-          export PUPPETEER_AVG_DURATION=`cat puppeteer.out|grep 'avg run'|sed 's/avg run duration (ms) //'`
-          echo "puppeteer avg duration: $PUPPETEER_AVG_DURATION"
-          test "$PUPPETEER_AVG_DURATION" -le "$MAX_AVG_DURATION"
-
   demo-scripts:
     name: demo-scripts
     needs: zig-build-release
@@ -140,15 +93,29 @@ jobs:
       - name: run end to end tests
         run: |
           ./lightpanda serve & echo $! > LPD.pid
-          go run runner/main.go --verbose
+          go run runner/main.go
           kill `cat LPD.pid`
 
+      - name: build proxy
+        run: |
+          cd proxy
+          go build
+
+      - name: run end to end tests through proxy
+        run: |
+          ./proxy/proxy & echo $! > PROXY.id
+          ./lightpanda serve --http_proxy 'http://127.0.0.1:3000' & echo $! > LPD.pid
+          go run runner/main.go
+          kill `cat LPD.pid` `cat PROXY.id`
+
   cdp-and-hyperfine-bench:
     name: cdp-and-hyperfine-bench
     needs: zig-build-release
 
-    # Don't execute on PR
-    if: github.event_name != 'pull_request'
+    env:
+      MAX_MEMORY: 27000
+      MAX_AVG_DURATION: 23
+      LIGHTPANDA_DISABLE_TELEMETRY: true
 
     # use a self host runner.
     runs-on: lpd-bench-hetzner
@@ -185,6 +152,18 @@ jobs:
       - name: puppeteer result
         run: cat puppeteer.out
 
+      - name: memory regression
+        run: |
+          export LPD_VmHWM=`cat LPD.VmHWM`
+          echo "Peak resident set size: $LPD_VmHWM"
+          test "$LPD_VmHWM" -le "$MAX_MEMORY"
+
+      - name: duration regression
+        run: |
+          export PUPPETEER_AVG_DURATION=`cat puppeteer.out|grep 'avg run'|sed 's/avg run duration (ms) //'`
+          echo "puppeteer avg duration: $PUPPETEER_AVG_DURATION"
+          test "$PUPPETEER_AVG_DURATION" -le "$MAX_AVG_DURATION"
+
       - name: json output
         run: |
           export AVG_DURATION=`cat puppeteer.out|grep 'avg run'|sed 's/avg run duration (ms) //'`

.github/workflows/zig-fmt.yml

@@ -1,7 +1,7 @@
 name: zig-fmt
 
 env:
-  ZIG_VERSION: 0.14.1
+  ZIG_VERSION: 0.15.1
 
 on:
   pull_request:

.gitmodules

@@ -19,3 +19,15 @@
 [submodule "vendor/mimalloc"]
 	path = vendor/mimalloc
 	url = https://github.com/microsoft/mimalloc.git/
+[submodule "vendor/nghttp2"]
+	path = vendor/nghttp2
+	url = https://github.com/nghttp2/nghttp2.git
+[submodule "vendor/mbedtls"]
+	path = vendor/mbedtls
+	url = https://github.com/Mbed-TLS/mbedtls.git
+[submodule "vendor/zlib"]
+	path = vendor/zlib
+	url = https://github.com/madler/zlib.git
+[submodule "vendor/curl"]
+	path = vendor/curl
+	url = https://github.com/curl/curl.git

Dockerfile

@@ -1,11 +1,11 @@
-FROM ubuntu:24.04
+FROM debian:stable
 
 ARG MINISIG=0.12
-ARG ZIG=0.14.1
+ARG ZIG=0.15.1
 ARG ZIG_MINISIG=RWSGOq2NVecA2UPNdBUZykf1CCb147pkmdtYxgb3Ti+JO/wCYvhbAb/U
-ARG ARCH=x86_64
 ARG V8=13.6.233.8
-ARG ZIG_V8=v0.1.24
+ARG ZIG_V8=v0.1.28
+ARG TARGETPLATFORM
 
 RUN apt-get update -yq && \
     apt-get install -yq xz-utils \
@@ -20,30 +20,19 @@ RUN curl --fail -L -O https://github.com/jedisct1/minisign/releases/download/${M
     tar xvzf minisign-${MINISIG}-linux.tar.gz
 
 # install zig
-RUN curl --fail -L -O https://ziglang.org/download/${ZIG}/zig-${ARCH}-linux-${ZIG}.tar.xz
-RUN curl --fail -L -O https://ziglang.org/download/${ZIG}/zig-${ARCH}-linux-${ZIG}.tar.xz.minisig
-
-RUN minisign-linux/${ARCH}/minisign -Vm zig-${ARCH}-linux-${ZIG}.tar.xz -P ${ZIG_MINISIG}
-
-# clean minisg
-RUN rm -fr minisign-0.11-linux.tar.gz minisign-linux
-
-# install zig
-RUN tar xvf zig-${ARCH}-linux-${ZIG}.tar.xz && \
+RUN case $TARGETPLATFORM in \
+    "linux/arm64") ARCH="aarch64" ;; \
+    *) ARCH="x86_64" ;; \
+    esac && \
+    curl --fail -L -O https://ziglang.org/download/${ZIG}/zig-${ARCH}-linux-${ZIG}.tar.xz && \
+    curl --fail -L -O https://ziglang.org/download/${ZIG}/zig-${ARCH}-linux-${ZIG}.tar.xz.minisig && \
+    minisign-linux/${ARCH}/minisign -Vm zig-${ARCH}-linux-${ZIG}.tar.xz -P ${ZIG_MINISIG} && \
+    tar xvf zig-${ARCH}-linux-${ZIG}.tar.xz && \
     mv zig-${ARCH}-linux-${ZIG} /usr/local/lib && \
     ln -s /usr/local/lib/zig-${ARCH}-linux-${ZIG}/zig /usr/local/bin/zig
 
-# clean up zig install
-RUN rm -fr zig-${ARCH}-linux-${ZIG}.tar.xz zig-${ARCH}-linux-${ZIG}.tar.xz.minisig
-
-# force use of http instead of ssh with github
-RUN cat <<EOF > /root/.gitconfig
-[url "https://github.com/"]
-    insteadOf="git@github.com:"
-EOF
-
 # clone lightpanda
-RUN git clone git@github.com:lightpanda-io/browser.git
+RUN git clone https://github.com/lightpanda-io/browser.git
 
 WORKDIR /browser
 
@@ -56,14 +45,18 @@ RUN make install-libiconv && \
     make install-mimalloc
 
 # download and install v8
-RUN curl --fail -L -o libc_v8.a https://github.com/lightpanda-io/zig-v8-fork/releases/download/${ZIG_V8}/libc_v8_${V8}_linux_${ARCH}.a && \
+RUN case $TARGETPLATFORM in \
+    "linux/arm64") ARCH="aarch64" ;; \
+    *) ARCH="x86_64" ;; \
+    esac && \
+    curl --fail -L -o libc_v8.a https://github.com/lightpanda-io/zig-v8-fork/releases/download/${ZIG_V8}/libc_v8_${V8}_linux_${ARCH}.a && \
     mkdir -p v8/out/linux/release/obj/zig/ && \
     mv libc_v8.a v8/out/linux/release/obj/zig/libc_v8.a
 
 # build release
 RUN make build
 
-FROM ubuntu:24.04
+FROM debian:stable-slim
 
 # copy ca certificates
 COPY --from=0 /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt

README.md

@@ -18,7 +18,7 @@ Lightpanda is the open-source browser made for headless usage:
 
 - Javascript execution
 - Support of Web APIs (partial, WIP)
-- Compatible with Playwright[^1], Puppeteer through CDP (WIP)
+- Compatible with Playwright[^1], Puppeteer, chromedp through CDP
 
 Fast web automation for AI agents, LLM training, scraping and testing:
 
@@ -41,7 +41,8 @@ Due to the nature of Playwright, a script that works with the current version of
 
 ## Quick start
 
-### Install from the nightly builds
+### Install
+**Install from the nightly builds**
 
 You can download the last binary from the [nightly
 builds](https://github.com/lightpanda-io/browser/releases/tag/nightly) for
@@ -64,6 +65,16 @@ chmod a+x ./lightpanda
 The Lightpanda browser is compatible to run on windows inside WSL. Follow the Linux instruction for installation from a WSL terminal.
 It is recommended to install clients like Puppeteer on the Windows host.
 
+**Install from Docker**
+
+Lightpanda provides [official Docker
+images](https://hub.docker.com/r/lightpanda/browser) for both Linux amd64 and
+arm64 architectures.
+The following command fetches the Docker image and starts a new container exposing Lightpanda's CDP server on port `9222`.
+```console
+docker run -d --name lightpanda -p 9222:9222 lightpanda/browser:nightly
+```
+
 ### Dump a URL
 
 ```console
@@ -124,21 +135,26 @@ By default, Lightpanda collects and sends usage telemetry. This can be disabled
 
 ## Status
 
-Lightpanda is still a work in progress and is currently at a Beta stage.
-
-:warning: You should expect most websites to fail or crash.
+Lightpanda is in Beta and currently a work in progress. Stability and coverage are improving and many websites now work.
+You may still encounter errors or crashes. Please open an issue with specifics if so.
 
 Here are the key features we have implemented:
 
-- [x] HTTP loader
+- [x] HTTP loader (based on Libcurl)
 - [x] HTML parser and DOM tree (based on Netsurf libs)
 - [x] Javascript support (v8)
-- [x] Basic DOM APIs
+- [x] DOM APIs
 - [x] Ajax
   - [x] XHR API
-  - [x] Fetch API
+  - [x] Fetch API (polyfill)
 - [x] DOM dump
-- [x] Basic CDP/websockets server
+- [x] CDP/websockets server
+- [x] Click
+- [x] Input form
+- [x] Cookies
+- [x] Custom HTTP headers
+- [x] Proxy support
+- [x] Network interception
 
 NOTE: There are hundreds of Web APIs. Developing a browser (even just for headless mode) is a huge task. Coverage will increase over time.
 
@@ -148,11 +164,12 @@ You can also follow the progress of our Javascript support in our dedicated [zig
 
 ### Prerequisites
 
-Lightpanda is written with [Zig](https://ziglang.org/) `0.14.1`. You have to
+Lightpanda is written with [Zig](https://ziglang.org/) `0.15.1`. You have to
 install it with the right version in order to build the project.
 
 Lightpanda also depends on
 [zig-js-runtime](https://github.com/lightpanda-io/zig-js-runtime/) (with v8),
+[Libcurl](https://curl.se/libcurl/),
 [Netsurf libs](https://www.netsurf-browser.org/) and
 [Mimalloc](https://microsoft.github.io/mimalloc).
 

build.zig

@@ -19,11 +19,13 @@
 const std = @import("std");
 const builtin = @import("builtin");
 
+const Build = std.Build;
+
 /// Do not rename this constant. It is scanned by some scripts to determine
 /// which zig version to install.
-const recommended_zig_version = "0.14.1";
+const recommended_zig_version = "0.15.1";
 
-pub fn build(b: *std.Build) !void {
+pub fn build(b: *Build) !void {
     switch (comptime builtin.zig_version.order(std.SemanticVersion.parse(recommended_zig_version) catch unreachable)) {
         .eq => {},
         .lt => {
@@ -47,6 +49,18 @@ pub fn build(b: *std.Build) !void {
     const target = b.standardTargetOptions(.{});
     const optimize = b.standardOptimizeOption(.{});
 
+    // We're still using llvm because the new x86 backend seems to crash
+    // with v8. This can be reproduced in zig-v8-fork.
+
+    const lightpanda_module = b.addModule("lightpanda", .{
+        .root_source_file = b.path("src/main.zig"),
+        .target = target,
+        .optimize = optimize,
+        .link_libc = true,
+        .link_libcpp = true,
+    });
+    try addDependencies(b, lightpanda_module, opts);
+
     {
         // browser
         // -------
@@ -54,12 +68,9 @@ pub fn build(b: *std.Build) !void {
         // compile and install
         const exe = b.addExecutable(.{
             .name = "lightpanda",
-            .target = target,
-            .optimize = optimize,
-            .root_source_file = b.path("src/main.zig"),
+            .use_llvm = true,
+            .root_module = lightpanda_module,
         });
-
-        try common(b, opts, exe);
         b.installArtifact(exe);
 
         // run
@@ -73,6 +84,54 @@ pub fn build(b: *std.Build) !void {
         run_step.dependOn(&run_cmd.step);
     }
 
+    {
+        // tests
+        // ----
+
+        // compile
+        const tests = b.addTest(.{
+            .root_module = lightpanda_module,
+            .use_llvm = true,
+            .test_runner = .{ .path = b.path("src/test_runner.zig"), .mode = .simple },
+        });
+
+        const run_tests = b.addRunArtifact(tests);
+        if (b.args) |args| {
+            run_tests.addArgs(args);
+        }
+
+        // step
+        const tests_step = b.step("test", "Run unit tests");
+        tests_step.dependOn(&run_tests.step);
+    }
+
+    {
+        // wpt
+        // -----
+        const wpt_module = b.createModule(.{
+            .root_source_file = b.path("src/main_wpt.zig"),
+            .target = target,
+            .optimize = optimize,
+        });
+        try addDependencies(b, wpt_module, opts);
+
+        // compile and install
+        const wpt = b.addExecutable(.{
+            .name = "lightpanda-wpt",
+            .use_llvm = true,
+            .root_module = wpt_module,
+        });
+
+        // run
+        const wpt_cmd = b.addRunArtifact(wpt);
+        if (b.args) |args| {
+            wpt_cmd.addArgs(args);
+        }
+        // step
+        const wpt_step = b.step("wpt", "WPT tests");
+        wpt_step.dependOn(&wpt_cmd.step);
+    }
+
     {
         // get v8
         // -------
@@ -90,63 +149,19 @@ pub fn build(b: *std.Build) !void {
         const build_step = b.step("build-v8", "Build v8");
         build_step.dependOn(&build_v8.step);
     }
-
-    {
-        // tests
-        // ----
-
-        // compile
-        const tests = b.addTest(.{
-            .root_source_file = b.path("src/main.zig"),
-            .test_runner = .{ .path = b.path("src/test_runner.zig"), .mode = .simple },
-            .target = target,
-            .optimize = optimize,
-        });
-        try common(b, opts, tests);
-
-        const run_tests = b.addRunArtifact(tests);
-        if (b.args) |args| {
-            run_tests.addArgs(args);
-        }
-
-        // step
-        const tests_step = b.step("test", "Run unit tests");
-        tests_step.dependOn(&run_tests.step);
-    }
-
-    {
-        // wpt
-        // -----
-
-        // compile and install
-        const wpt = b.addExecutable(.{
-            .name = "lightpanda-wpt",
-            .root_source_file = b.path("src/main_wpt.zig"),
-            .target = target,
-            .optimize = optimize,
-        });
-        try common(b, opts, wpt);
-
-        // run
-        const wpt_cmd = b.addRunArtifact(wpt);
-        if (b.args) |args| {
-            wpt_cmd.addArgs(args);
-        }
-        // step
-        const wpt_step = b.step("wpt", "WPT tests");
-        wpt_step.dependOn(&wpt_cmd.step);
-    }
 }
 
-fn common(b: *std.Build, opts: *std.Build.Step.Options, step: *std.Build.Step.Compile) !void {
-    const mod = step.root_module;
-    const target = mod.resolved_target.?;
-    const optimize = mod.optimize.?;
-    const dep_opts = .{ .target = target, .optimize = optimize };
+fn addDependencies(b: *Build, mod: *Build.Module, opts: *Build.Step.Options) !void {
+    try moduleNetSurf(b, mod);
+    mod.addImport("build_config", opts.createModule());
 
-    try moduleNetSurf(b, step, target);
-    mod.addImport("tls", b.dependency("tls", dep_opts).module("tls"));
-    mod.addImport("tigerbeetle-io", b.dependency("tigerbeetle_io", .{}).module("tigerbeetle_io"));
+    const target = mod.resolved_target.?;
+    const dep_opts = .{
+        .target = target,
+        .optimize = mod.optimize.?,
+    };
+
+    mod.addIncludePath(b.path("vendor/lightpanda"));
 
     {
         // v8
@@ -156,11 +171,7 @@ fn common(b: *std.Build, opts: *std.Build.Step.Options, step: *std.Build.Step.Co
         const v8_mod = b.dependency("v8", dep_opts).module("v8");
         v8_mod.addOptions("default_exports", v8_opts);
         mod.addImport("v8", v8_mod);
-    }
 
-    mod.link_libcpp = true;
-
-    {
         const release_dir = if (mod.optimize.? == .Debug) "debug" else "release";
         const os = switch (target.result.os.tag) {
             .linux => "linux",
@@ -181,21 +192,211 @@ fn common(b: *std.Build, opts: *std.Build.Step.Options, step: *std.Build.Step.Co
             );
         };
         mod.addObjectFile(mod.owner.path(lib_path));
+
+        switch (target.result.os.tag) {
+            .macos => {
+                // v8 has a dependency, abseil-cpp, which, on Mac, uses CoreFoundation
+                mod.addSystemFrameworkPath(.{ .cwd_relative = "/System/Library/Frameworks" });
+                mod.linkFramework("CoreFoundation", .{});
+            },
+            else => {},
+        }
     }
 
-    switch (target.result.os.tag) {
-        .macos => {
-            // v8 has a dependency, abseil-cpp, which, on Mac, uses CoreFoundation
-            mod.addSystemFrameworkPath(.{ .cwd_relative = "/System/Library/Frameworks" });
-            mod.linkFramework("CoreFoundation", .{});
-        },
-        else => {},
-    }
+    {
+        //curl
+        {
+            const is_linux = target.result.os.tag == .linux;
+            if (is_linux) {
+                mod.addCMacro("HAVE_LINUX_TCP_H", "1");
+                mod.addCMacro("HAVE_MSG_NOSIGNAL", "1");
+                mod.addCMacro("HAVE_GETHOSTBYNAME_R", "1");
+            }
+            mod.addCMacro("_FILE_OFFSET_BITS", "64");
+            mod.addCMacro("BUILDING_LIBCURL", "1");
+            mod.addCMacro("CURL_DISABLE_AWS", "1");
+            mod.addCMacro("CURL_DISABLE_DICT", "1");
+            mod.addCMacro("CURL_DISABLE_DOH", "1");
+            mod.addCMacro("CURL_DISABLE_FILE", "1");
+            mod.addCMacro("CURL_DISABLE_FTP", "1");
+            mod.addCMacro("CURL_DISABLE_GOPHER", "1");
+            mod.addCMacro("CURL_DISABLE_KERBEROS", "1");
+            mod.addCMacro("CURL_DISABLE_IMAP", "1");
+            mod.addCMacro("CURL_DISABLE_IPFS", "1");
+            mod.addCMacro("CURL_DISABLE_LDAP", "1");
+            mod.addCMacro("CURL_DISABLE_LDAPS", "1");
+            mod.addCMacro("CURL_DISABLE_MQTT", "1");
+            mod.addCMacro("CURL_DISABLE_NTLM", "1");
+            mod.addCMacro("CURL_DISABLE_PROGRESS_METER", "1");
+            mod.addCMacro("CURL_DISABLE_POP3", "1");
+            mod.addCMacro("CURL_DISABLE_RTSP", "1");
+            mod.addCMacro("CURL_DISABLE_SMB", "1");
+            mod.addCMacro("CURL_DISABLE_SMTP", "1");
+            mod.addCMacro("CURL_DISABLE_TELNET", "1");
+            mod.addCMacro("CURL_DISABLE_TFTP", "1");
+            mod.addCMacro("CURL_EXTERN_SYMBOL", "__attribute__ ((__visibility__ (\"default\"))");
+            mod.addCMacro("CURL_OS", if (is_linux) "\"Linux\"" else "\"mac\"");
+            mod.addCMacro("CURL_STATICLIB", "1");
+            mod.addCMacro("ENABLE_IPV6", "1");
+            mod.addCMacro("HAVE_ALARM", "1");
+            mod.addCMacro("HAVE_ALLOCA_H", "1");
+            mod.addCMacro("HAVE_ARPA_INET_H", "1");
+            mod.addCMacro("HAVE_ARPA_TFTP_H", "1");
+            mod.addCMacro("HAVE_ASSERT_H", "1");
+            mod.addCMacro("HAVE_BASENAME", "1");
+            mod.addCMacro("HAVE_BOOL_T", "1");
+            mod.addCMacro("HAVE_BUILTIN_AVAILABLE", "1");
+            mod.addCMacro("HAVE_CLOCK_GETTIME_MONOTONIC", "1");
+            mod.addCMacro("HAVE_DLFCN_H", "1");
+            mod.addCMacro("HAVE_ERRNO_H", "1");
+            mod.addCMacro("HAVE_FCNTL", "1");
+            mod.addCMacro("HAVE_FCNTL_H", "1");
+            mod.addCMacro("HAVE_FCNTL_O_NONBLOCK", "1");
+            mod.addCMacro("HAVE_FREEADDRINFO", "1");
+            mod.addCMacro("HAVE_FSETXATTR", "1");
+            mod.addCMacro("HAVE_FSETXATTR_5", "1");
+            mod.addCMacro("HAVE_FTRUNCATE", "1");
+            mod.addCMacro("HAVE_GETADDRINFO", "1");
+            mod.addCMacro("HAVE_GETEUID", "1");
+            mod.addCMacro("HAVE_GETHOSTBYNAME", "1");
+            mod.addCMacro("HAVE_GETHOSTBYNAME_R_6", "1");
+            mod.addCMacro("HAVE_GETHOSTNAME", "1");
+            mod.addCMacro("HAVE_GETPEERNAME", "1");
+            mod.addCMacro("HAVE_GETPPID", "1");
+            mod.addCMacro("HAVE_GETPPID", "1");
+            mod.addCMacro("HAVE_GETPROTOBYNAME", "1");
+            mod.addCMacro("HAVE_GETPWUID", "1");
+            mod.addCMacro("HAVE_GETPWUID_R", "1");
+            mod.addCMacro("HAVE_GETRLIMIT", "1");
+            mod.addCMacro("HAVE_GETSOCKNAME", "1");
+            mod.addCMacro("HAVE_GETTIMEOFDAY", "1");
+            mod.addCMacro("HAVE_GMTIME_R", "1");
+            mod.addCMacro("HAVE_IDN2_H", "1");
+            mod.addCMacro("HAVE_IF_NAMETOINDEX", "1");
+            mod.addCMacro("HAVE_IFADDRS_H", "1");
+            mod.addCMacro("HAVE_INET_ADDR", "1");
+            mod.addCMacro("HAVE_INET_PTON", "1");
+            mod.addCMacro("HAVE_INTTYPES_H", "1");
+            mod.addCMacro("HAVE_IOCTL", "1");
+            mod.addCMacro("HAVE_IOCTL_FIONBIO", "1");
+            mod.addCMacro("HAVE_IOCTL_SIOCGIFADDR", "1");
+            mod.addCMacro("HAVE_LDAP_URL_PARSE", "1");
+            mod.addCMacro("HAVE_LIBGEN_H", "1");
+            mod.addCMacro("HAVE_LIBZ", "1");
+            mod.addCMacro("HAVE_LL", "1");
+            mod.addCMacro("HAVE_LOCALE_H", "1");
+            mod.addCMacro("HAVE_LOCALTIME_R", "1");
+            mod.addCMacro("HAVE_LONGLONG", "1");
+            mod.addCMacro("HAVE_MALLOC_H", "1");
+            mod.addCMacro("HAVE_MEMORY_H", "1");
+            mod.addCMacro("HAVE_NET_IF_H", "1");
+            mod.addCMacro("HAVE_NETDB_H", "1");
+            mod.addCMacro("HAVE_NETINET_IN_H", "1");
+            mod.addCMacro("HAVE_NETINET_TCP_H", "1");
+            mod.addCMacro("HAVE_PIPE", "1");
+            mod.addCMacro("HAVE_POLL", "1");
+            mod.addCMacro("HAVE_POLL_FINE", "1");
+            mod.addCMacro("HAVE_POLL_H", "1");
+            mod.addCMacro("HAVE_POSIX_STRERROR_R", "1");
+            mod.addCMacro("HAVE_PTHREAD_H", "1");
+            mod.addCMacro("HAVE_PWD_H", "1");
+            mod.addCMacro("HAVE_RECV", "1");
+            mod.addCMacro("HAVE_SA_FAMILY_T", "1");
+            mod.addCMacro("HAVE_SELECT", "1");
+            mod.addCMacro("HAVE_SEND", "1");
+            mod.addCMacro("HAVE_SETJMP_H", "1");
+            mod.addCMacro("HAVE_SETLOCALE", "1");
+            mod.addCMacro("HAVE_SETRLIMIT", "1");
+            mod.addCMacro("HAVE_SETSOCKOPT", "1");
+            mod.addCMacro("HAVE_SIGACTION", "1");
+            mod.addCMacro("HAVE_SIGINTERRUPT", "1");
+            mod.addCMacro("HAVE_SIGNAL", "1");
+            mod.addCMacro("HAVE_SIGNAL_H", "1");
+            mod.addCMacro("HAVE_SIGSETJMP", "1");
+            mod.addCMacro("HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID", "1");
+            mod.addCMacro("HAVE_SOCKET", "1");
+            mod.addCMacro("HAVE_STDBOOL_H", "1");
+            mod.addCMacro("HAVE_STDINT_H", "1");
+            mod.addCMacro("HAVE_STDIO_H", "1");
+            mod.addCMacro("HAVE_STDLIB_H", "1");
+            mod.addCMacro("HAVE_STRCASECMP", "1");
+            mod.addCMacro("HAVE_STRDUP", "1");
+            mod.addCMacro("HAVE_STRERROR_R", "1");
+            mod.addCMacro("HAVE_STRING_H", "1");
+            mod.addCMacro("HAVE_STRINGS_H", "1");
+            mod.addCMacro("HAVE_STRSTR", "1");
+            mod.addCMacro("HAVE_STRTOK_R", "1");
+            mod.addCMacro("HAVE_STRTOLL", "1");
+            mod.addCMacro("HAVE_STRUCT_SOCKADDR_STORAGE", "1");
+            mod.addCMacro("HAVE_STRUCT_TIMEVAL", "1");
+            mod.addCMacro("HAVE_SYS_IOCTL_H", "1");
+            mod.addCMacro("HAVE_SYS_PARAM_H", "1");
+            mod.addCMacro("HAVE_SYS_POLL_H", "1");
+            mod.addCMacro("HAVE_SYS_RESOURCE_H", "1");
+            mod.addCMacro("HAVE_SYS_SELECT_H", "1");
+            mod.addCMacro("HAVE_SYS_SOCKET_H", "1");
+            mod.addCMacro("HAVE_SYS_STAT_H", "1");
+            mod.addCMacro("HAVE_SYS_TIME_H", "1");
+            mod.addCMacro("HAVE_SYS_TYPES_H", "1");
+            mod.addCMacro("HAVE_SYS_UIO_H", "1");
+            mod.addCMacro("HAVE_SYS_UN_H", "1");
+            mod.addCMacro("HAVE_TERMIO_H", "1");
+            mod.addCMacro("HAVE_TERMIOS_H", "1");
+            mod.addCMacro("HAVE_TIME_H", "1");
+            mod.addCMacro("HAVE_UNAME", "1");
+            mod.addCMacro("HAVE_UNISTD_H", "1");
+            mod.addCMacro("HAVE_UTIME", "1");
+            mod.addCMacro("HAVE_UTIME_H", "1");
+            mod.addCMacro("HAVE_UTIMES", "1");
+            mod.addCMacro("HAVE_VARIADIC_MACROS_C99", "1");
+            mod.addCMacro("HAVE_VARIADIC_MACROS_GCC", "1");
+            mod.addCMacro("HAVE_ZLIB_H", "1");
+            mod.addCMacro("RANDOM_FILE", "\"/dev/urandom\"");
+            mod.addCMacro("RECV_TYPE_ARG1", "int");
+            mod.addCMacro("RECV_TYPE_ARG2", "void *");
+            mod.addCMacro("RECV_TYPE_ARG3", "size_t");
+            mod.addCMacro("RECV_TYPE_ARG4", "int");
+            mod.addCMacro("RECV_TYPE_RETV", "ssize_t");
+            mod.addCMacro("SEND_QUAL_ARG2", "const");
+            mod.addCMacro("SEND_TYPE_ARG1", "int");
+            mod.addCMacro("SEND_TYPE_ARG2", "void *");
+            mod.addCMacro("SEND_TYPE_ARG3", "size_t");
+            mod.addCMacro("SEND_TYPE_ARG4", "int");
+            mod.addCMacro("SEND_TYPE_RETV", "ssize_t");
+            mod.addCMacro("SIZEOF_CURL_OFF_T", "8");
+            mod.addCMacro("SIZEOF_INT", "4");
+            mod.addCMacro("SIZEOF_LONG", "8");
+            mod.addCMacro("SIZEOF_OFF_T", "8");
+            mod.addCMacro("SIZEOF_SHORT", "2");
+            mod.addCMacro("SIZEOF_SIZE_T", "8");
+            mod.addCMacro("SIZEOF_TIME_T", "8");
+            mod.addCMacro("STDC_HEADERS", "1");
+            mod.addCMacro("TIME_WITH_SYS_TIME", "1");
+            mod.addCMacro("USE_NGHTTP2", "1");
+            mod.addCMacro("USE_MBEDTLS", "1");
+            mod.addCMacro("USE_THREADS_POSIX", "1");
+            mod.addCMacro("USE_UNIX_SOCKETS", "1");
+        }
 
-    mod.addImport("build_config", opts.createModule());
+        try buildZlib(b, mod);
+        try buildMbedtls(b, mod);
+        try buildNghttp2(b, mod);
+        try buildCurl(b, mod);
+
+        switch (target.result.os.tag) {
+            .macos => {
+                // needed for proxying on mac
+                mod.addSystemFrameworkPath(.{ .cwd_relative = "/System/Library/Frameworks" });
+                mod.linkFramework("CoreFoundation", .{});
+                mod.linkFramework("SystemConfiguration", .{});
+            },
+            else => {},
+        }
+    }
 }
 
-fn moduleNetSurf(b: *std.Build, step: *std.Build.Step.Compile, target: std.Build.ResolvedTarget) !void {
+fn moduleNetSurf(b: *Build, mod: *Build.Module) !void {
+    const target = mod.resolved_target.?;
     const os = target.result.os.tag;
     const arch = target.result.cpu.arch;
 
@@ -210,8 +411,8 @@ fn moduleNetSurf(b: *std.Build, step: *std.Build.Step.Compile, target: std.Build
         "vendor/libiconv/out/{s}-{s}/lib/libiconv.a",
         .{ @tagName(os), @tagName(arch) },
     );
-    step.addObjectFile(b.path(libiconv_lib_path));
-    step.addIncludePath(b.path(libiconv_include_path));
+    mod.addObjectFile(b.path(libiconv_lib_path));
+    mod.addIncludePath(b.path(libiconv_include_path));
 
     {
         // mimalloc
@@ -221,8 +422,8 @@ fn moduleNetSurf(b: *std.Build, step: *std.Build.Step.Compile, target: std.Build
             mimalloc ++ "/out/{s}-{s}/lib/libmimalloc.a",
             .{ @tagName(os), @tagName(arch) },
         );
-        step.addObjectFile(b.path(lib_path));
-        step.addIncludePath(b.path(mimalloc ++ "/include"));
+        mod.addObjectFile(b.path(lib_path));
+        mod.addIncludePath(b.path(mimalloc ++ "/include"));
     }
 
     // netsurf libs
@@ -232,7 +433,7 @@ fn moduleNetSurf(b: *std.Build, step: *std.Build.Step.Compile, target: std.Build
         ns ++ "/out/{s}-{s}/include",
         .{ @tagName(os), @tagName(arch) },
     );
-    step.addIncludePath(b.path(ns_include_path));
+    mod.addIncludePath(b.path(ns_include_path));
 
     const libs: [4][]const u8 = .{
         "libdom",
@@ -246,7 +447,379 @@ fn moduleNetSurf(b: *std.Build, step: *std.Build.Step.Compile, target: std.Build
             ns ++ "/out/{s}-{s}/lib/" ++ lib ++ ".a",
             .{ @tagName(os), @tagName(arch) },
         );
-        step.addObjectFile(b.path(ns_lib_path));
-        step.addIncludePath(b.path(ns ++ "/" ++ lib ++ "/src"));
+        mod.addObjectFile(b.path(ns_lib_path));
+        mod.addIncludePath(b.path(ns ++ "/" ++ lib ++ "/src"));
     }
 }
+
+fn buildZlib(b: *Build, m: *Build.Module) !void {
+    const zlib = b.addLibrary(.{
+        .name = "zlib",
+        .root_module = m,
+    });
+
+    const root = "vendor/zlib/";
+    zlib.installHeader(b.path(root ++ "zlib.h"), "zlib.h");
+    zlib.installHeader(b.path(root ++ "zconf.h"), "zconf.h");
+    zlib.addCSourceFiles(.{ .flags = &.{
+        "-DHAVE_SYS_TYPES_H",
+        "-DHAVE_STDINT_H",
+        "-DHAVE_STDDEF_H",
+    }, .files = &.{
+        root ++ "adler32.c",
+        root ++ "compress.c",
+        root ++ "crc32.c",
+        root ++ "deflate.c",
+        root ++ "gzclose.c",
+        root ++ "gzlib.c",
+        root ++ "gzread.c",
+        root ++ "gzwrite.c",
+        root ++ "inflate.c",
+        root ++ "infback.c",
+        root ++ "inftrees.c",
+        root ++ "inffast.c",
+        root ++ "trees.c",
+        root ++ "uncompr.c",
+        root ++ "zutil.c",
+    } });
+}
+
+fn buildMbedtls(b: *Build, m: *Build.Module) !void {
+    const mbedtls = b.addLibrary(.{
+        .name = "mbedtls",
+        .root_module = m,
+    });
+
+    const root = "vendor/mbedtls/";
+    mbedtls.addIncludePath(b.path(root ++ "include"));
+    mbedtls.addIncludePath(b.path(root ++ "library"));
+
+    mbedtls.addCSourceFiles(.{ .flags = &.{}, .files = &.{
+        root ++ "library/aes.c",
+        root ++ "library/aesni.c",
+        root ++ "library/aesce.c",
+        root ++ "library/aria.c",
+        root ++ "library/asn1parse.c",
+        root ++ "library/asn1write.c",
+        root ++ "library/base64.c",
+        root ++ "library/bignum.c",
+        root ++ "library/bignum_core.c",
+        root ++ "library/bignum_mod.c",
+        root ++ "library/bignum_mod_raw.c",
+        root ++ "library/camellia.c",
+        root ++ "library/ccm.c",
+        root ++ "library/chacha20.c",
+        root ++ "library/chachapoly.c",
+        root ++ "library/cipher.c",
+        root ++ "library/cipher_wrap.c",
+        root ++ "library/constant_time.c",
+        root ++ "library/cmac.c",
+        root ++ "library/ctr_drbg.c",
+        root ++ "library/des.c",
+        root ++ "library/dhm.c",
+        root ++ "library/ecdh.c",
+        root ++ "library/ecdsa.c",
+        root ++ "library/ecjpake.c",
+        root ++ "library/ecp.c",
+        root ++ "library/ecp_curves.c",
+        root ++ "library/entropy.c",
+        root ++ "library/entropy_poll.c",
+        root ++ "library/error.c",
+        root ++ "library/gcm.c",
+        root ++ "library/hkdf.c",
+        root ++ "library/hmac_drbg.c",
+        root ++ "library/lmots.c",
+        root ++ "library/lms.c",
+        root ++ "library/md.c",
+        root ++ "library/md5.c",
+        root ++ "library/memory_buffer_alloc.c",
+        root ++ "library/nist_kw.c",
+        root ++ "library/oid.c",
+        root ++ "library/padlock.c",
+        root ++ "library/pem.c",
+        root ++ "library/pk.c",
+        root ++ "library/pk_ecc.c",
+        root ++ "library/pk_wrap.c",
+        root ++ "library/pkcs12.c",
+        root ++ "library/pkcs5.c",
+        root ++ "library/pkparse.c",
+        root ++ "library/pkwrite.c",
+        root ++ "library/platform.c",
+        root ++ "library/platform_util.c",
+        root ++ "library/poly1305.c",
+        root ++ "library/psa_crypto.c",
+        root ++ "library/psa_crypto_aead.c",
+        root ++ "library/psa_crypto_cipher.c",
+        root ++ "library/psa_crypto_client.c",
+        root ++ "library/psa_crypto_ffdh.c",
+        root ++ "library/psa_crypto_driver_wrappers_no_static.c",
+        root ++ "library/psa_crypto_ecp.c",
+        root ++ "library/psa_crypto_hash.c",
+        root ++ "library/psa_crypto_mac.c",
+        root ++ "library/psa_crypto_pake.c",
+        root ++ "library/psa_crypto_rsa.c",
+        root ++ "library/psa_crypto_se.c",
+        root ++ "library/psa_crypto_slot_management.c",
+        root ++ "library/psa_crypto_storage.c",
+        root ++ "library/psa_its_file.c",
+        root ++ "library/psa_util.c",
+        root ++ "library/ripemd160.c",
+        root ++ "library/rsa.c",
+        root ++ "library/rsa_alt_helpers.c",
+        root ++ "library/sha1.c",
+        root ++ "library/sha3.c",
+        root ++ "library/sha256.c",
+        root ++ "library/sha512.c",
+        root ++ "library/threading.c",
+        root ++ "library/timing.c",
+        root ++ "library/version.c",
+        root ++ "library/version_features.c",
+        root ++ "library/pkcs7.c",
+        root ++ "library/x509.c",
+        root ++ "library/x509_create.c",
+        root ++ "library/x509_crl.c",
+        root ++ "library/x509_crt.c",
+        root ++ "library/x509_csr.c",
+        root ++ "library/x509write.c",
+        root ++ "library/x509write_crt.c",
+        root ++ "library/x509write_csr.c",
+        root ++ "library/debug.c",
+        root ++ "library/mps_reader.c",
+        root ++ "library/mps_trace.c",
+        root ++ "library/net_sockets.c",
+        root ++ "library/ssl_cache.c",
+        root ++ "library/ssl_ciphersuites.c",
+        root ++ "library/ssl_client.c",
+        root ++ "library/ssl_cookie.c",
+        root ++ "library/ssl_debug_helpers_generated.c",
+        root ++ "library/ssl_msg.c",
+        root ++ "library/ssl_ticket.c",
+        root ++ "library/ssl_tls.c",
+        root ++ "library/ssl_tls12_client.c",
+        root ++ "library/ssl_tls12_server.c",
+        root ++ "library/ssl_tls13_keys.c",
+        root ++ "library/ssl_tls13_server.c",
+        root ++ "library/ssl_tls13_client.c",
+        root ++ "library/ssl_tls13_generic.c",
+    } });
+}
+
+fn buildNghttp2(b: *Build, m: *Build.Module) !void {
+    const nghttp2 = b.addLibrary(.{
+        .name = "nghttp2",
+        .root_module = m,
+    });
+
+    const root = "vendor/nghttp2/";
+    nghttp2.addIncludePath(b.path(root ++ "lib"));
+    nghttp2.addIncludePath(b.path(root ++ "lib/includes"));
+    nghttp2.addCSourceFiles(.{ .flags = &.{
+        "-DNGHTTP2_STATICLIB",
+        "-DHAVE_NETINET_IN",
+        "-DHAVE_TIME_H",
+    }, .files = &.{
+        root ++ "lib/sfparse.c",
+        root ++ "lib/nghttp2_alpn.c",
+        root ++ "lib/nghttp2_buf.c",
+        root ++ "lib/nghttp2_callbacks.c",
+        root ++ "lib/nghttp2_debug.c",
+        root ++ "lib/nghttp2_extpri.c",
+        root ++ "lib/nghttp2_frame.c",
+        root ++ "lib/nghttp2_hd.c",
+        root ++ "lib/nghttp2_hd_huffman.c",
+        root ++ "lib/nghttp2_hd_huffman_data.c",
+        root ++ "lib/nghttp2_helper.c",
+        root ++ "lib/nghttp2_http.c",
+        root ++ "lib/nghttp2_map.c",
+        root ++ "lib/nghttp2_mem.c",
+        root ++ "lib/nghttp2_option.c",
+        root ++ "lib/nghttp2_outbound_item.c",
+        root ++ "lib/nghttp2_pq.c",
+        root ++ "lib/nghttp2_priority_spec.c",
+        root ++ "lib/nghttp2_queue.c",
+        root ++ "lib/nghttp2_rcbuf.c",
+        root ++ "lib/nghttp2_session.c",
+        root ++ "lib/nghttp2_stream.c",
+        root ++ "lib/nghttp2_submit.c",
+        root ++ "lib/nghttp2_version.c",
+        root ++ "lib/nghttp2_ratelim.c",
+        root ++ "lib/nghttp2_time.c",
+    } });
+}
+
+fn buildCurl(b: *Build, m: *Build.Module) !void {
+    const curl = b.addLibrary(.{
+        .name = "curl",
+        .root_module = m,
+    });
+
+    const root = "vendor/curl/";
+
+    curl.addIncludePath(b.path(root ++ "lib"));
+    curl.addIncludePath(b.path(root ++ "include"));
+    curl.addCSourceFiles(.{
+        .flags = &.{},
+        .files = &.{
+            root ++ "lib/altsvc.c",
+            root ++ "lib/amigaos.c",
+            root ++ "lib/asyn-ares.c",
+            root ++ "lib/asyn-base.c",
+            root ++ "lib/asyn-thrdd.c",
+            root ++ "lib/bufq.c",
+            root ++ "lib/bufref.c",
+            root ++ "lib/cf-h1-proxy.c",
+            root ++ "lib/cf-h2-proxy.c",
+            root ++ "lib/cf-haproxy.c",
+            root ++ "lib/cf-https-connect.c",
+            root ++ "lib/cf-socket.c",
+            root ++ "lib/cfilters.c",
+            root ++ "lib/conncache.c",
+            root ++ "lib/connect.c",
+            root ++ "lib/content_encoding.c",
+            root ++ "lib/cookie.c",
+            root ++ "lib/cshutdn.c",
+            root ++ "lib/curl_addrinfo.c",
+            root ++ "lib/curl_des.c",
+            root ++ "lib/curl_endian.c",
+            root ++ "lib/curl_fnmatch.c",
+            root ++ "lib/curl_get_line.c",
+            root ++ "lib/curl_gethostname.c",
+            root ++ "lib/curl_gssapi.c",
+            root ++ "lib/curl_memrchr.c",
+            root ++ "lib/curl_ntlm_core.c",
+            root ++ "lib/curl_range.c",
+            root ++ "lib/curl_rtmp.c",
+            root ++ "lib/curl_sasl.c",
+            root ++ "lib/curl_sha512_256.c",
+            root ++ "lib/curl_sspi.c",
+            root ++ "lib/curl_threads.c",
+            root ++ "lib/curl_trc.c",
+            root ++ "lib/cw-out.c",
+            root ++ "lib/cw-pause.c",
+            root ++ "lib/dict.c",
+            root ++ "lib/doh.c",
+            root ++ "lib/dynhds.c",
+            root ++ "lib/easy.c",
+            root ++ "lib/easygetopt.c",
+            root ++ "lib/easyoptions.c",
+            root ++ "lib/escape.c",
+            root ++ "lib/fake_addrinfo.c",
+            root ++ "lib/file.c",
+            root ++ "lib/fileinfo.c",
+            root ++ "lib/fopen.c",
+            root ++ "lib/formdata.c",
+            root ++ "lib/ftp.c",
+            root ++ "lib/ftplistparser.c",
+            root ++ "lib/getenv.c",
+            root ++ "lib/getinfo.c",
+            root ++ "lib/gopher.c",
+            root ++ "lib/hash.c",
+            root ++ "lib/headers.c",
+            root ++ "lib/hmac.c",
+            root ++ "lib/hostip.c",
+            root ++ "lib/hostip4.c",
+            root ++ "lib/hostip6.c",
+            root ++ "lib/hsts.c",
+            root ++ "lib/http.c",
+            root ++ "lib/http1.c",
+            root ++ "lib/http2.c",
+            root ++ "lib/http_aws_sigv4.c",
+            root ++ "lib/http_chunks.c",
+            root ++ "lib/http_digest.c",
+            root ++ "lib/http_negotiate.c",
+            root ++ "lib/http_ntlm.c",
+            root ++ "lib/http_proxy.c",
+            root ++ "lib/httpsrr.c",
+            root ++ "lib/idn.c",
+            root ++ "lib/if2ip.c",
+            root ++ "lib/imap.c",
+            root ++ "lib/krb5.c",
+            root ++ "lib/ldap.c",
+            root ++ "lib/llist.c",
+            root ++ "lib/macos.c",
+            root ++ "lib/md4.c",
+            root ++ "lib/md5.c",
+            root ++ "lib/memdebug.c",
+            root ++ "lib/mime.c",
+            root ++ "lib/mprintf.c",
+            root ++ "lib/mqtt.c",
+            root ++ "lib/multi.c",
+            root ++ "lib/multi_ev.c",
+            root ++ "lib/netrc.c",
+            root ++ "lib/noproxy.c",
+            root ++ "lib/openldap.c",
+            root ++ "lib/parsedate.c",
+            root ++ "lib/pingpong.c",
+            root ++ "lib/pop3.c",
+            root ++ "lib/progress.c",
+            root ++ "lib/psl.c",
+            root ++ "lib/rand.c",
+            root ++ "lib/rename.c",
+            root ++ "lib/request.c",
+            root ++ "lib/rtsp.c",
+            root ++ "lib/select.c",
+            root ++ "lib/sendf.c",
+            root ++ "lib/setopt.c",
+            root ++ "lib/sha256.c",
+            root ++ "lib/share.c",
+            root ++ "lib/slist.c",
+            root ++ "lib/smb.c",
+            root ++ "lib/smtp.c",
+            root ++ "lib/socketpair.c",
+            root ++ "lib/socks.c",
+            root ++ "lib/socks_gssapi.c",
+            root ++ "lib/socks_sspi.c",
+            root ++ "lib/speedcheck.c",
+            root ++ "lib/splay.c",
+            root ++ "lib/strcase.c",
+            root ++ "lib/strdup.c",
+            root ++ "lib/strequal.c",
+            root ++ "lib/strerror.c",
+            root ++ "lib/system_win32.c",
+            root ++ "lib/telnet.c",
+            root ++ "lib/tftp.c",
+            root ++ "lib/transfer.c",
+            root ++ "lib/uint-bset.c",
+            root ++ "lib/uint-hash.c",
+            root ++ "lib/uint-spbset.c",
+            root ++ "lib/uint-table.c",
+            root ++ "lib/url.c",
+            root ++ "lib/urlapi.c",
+            root ++ "lib/version.c",
+            root ++ "lib/ws.c",
+            root ++ "lib/curlx/base64.c",
+            root ++ "lib/curlx/dynbuf.c",
+            root ++ "lib/curlx/inet_ntop.c",
+            root ++ "lib/curlx/nonblock.c",
+            root ++ "lib/curlx/strparse.c",
+            root ++ "lib/curlx/timediff.c",
+            root ++ "lib/curlx/timeval.c",
+            root ++ "lib/curlx/wait.c",
+            root ++ "lib/curlx/warnless.c",
+            root ++ "lib/vquic/curl_ngtcp2.c",
+            root ++ "lib/vquic/curl_osslq.c",
+            root ++ "lib/vquic/curl_quiche.c",
+            root ++ "lib/vquic/vquic.c",
+            root ++ "lib/vquic/vquic-tls.c",
+            root ++ "lib/vauth/cleartext.c",
+            root ++ "lib/vauth/cram.c",
+            root ++ "lib/vauth/digest.c",
+            root ++ "lib/vauth/digest_sspi.c",
+            root ++ "lib/vauth/gsasl.c",
+            root ++ "lib/vauth/krb5_gssapi.c",
+            root ++ "lib/vauth/krb5_sspi.c",
+            root ++ "lib/vauth/ntlm.c",
+            root ++ "lib/vauth/ntlm_sspi.c",
+            root ++ "lib/vauth/oauth2.c",
+            root ++ "lib/vauth/spnego_gssapi.c",
+            root ++ "lib/vauth/spnego_sspi.c",
+            root ++ "lib/vauth/vauth.c",
+            root ++ "lib/vtls/cipher_suite.c",
+            root ++ "lib/vtls/mbedtls.c",
+            root ++ "lib/vtls/mbedtls_threadlock.c",
+            root ++ "lib/vtls/vtls.c",
+            root ++ "lib/vtls/vtls_scache.c",
+            root ++ "lib/vtls/x509asn1.c",
+        },
+    });
+}

build.zig.zon

@@ -4,19 +4,10 @@
     .version = "0.0.0",
     .fingerprint = 0xda130f3af836cea0,
     .dependencies = .{
-        .tls = .{
-            .url = "https://github.com/ianic/tls.zig/archive/b29a8b45fc59fc2d202769c4f54509bb9e17d0a2.tar.gz",
-            .hash = "tls-0.1.0-ER2e0uAxBQDm_TmSDdbiiyvAZoh4ejlDD4hW8Fl813xE",
-        },
-        .tigerbeetle_io = .{
-            .url = "https://github.com/lightpanda-io/tigerbeetle-io/archive/61d9652f1a957b7f4db723ea6aa0ce9635e840ce.tar.gz",
-            .hash = "tigerbeetle_io-0.0.0-ViLgxpyRBAB5BMfIcj3KMXfbJzwARs9uSl8aRy2OXULd",
-        },
         .v8 = .{
-            .url = "https://github.com/lightpanda-io/zig-v8-fork/archive/1d25fcf3ced688adca3c7a95a138771e4ebba692.tar.gz",
-            .hash = "v8-0.0.0-xddH61eyAwDICIkLAkfQcxsX4TMCKY80QiSUgNBQqx-u",
+            .url = "https://github.com/lightpanda-io/zig-v8-fork/archive/d3040a953e5a37290dae20e7ddf138b7aeb5e67d.tar.gz",
+            .hash = "v8-0.0.0-xddH6w_EAwA8vK0NAxfxfI7IcbnpkUAcXKNujn7qwnmY",
         },
-        //.v8 = .{ .path = "../zig-v8-fork" },
-        //.tigerbeetle_io = .{ .path = "../tigerbeetle-io" },
+        //.v8 = .{ .path = "../zig-v8-fork" }
     },
 }

flake.lock

@@ -1,5 +1,21 @@
 {
   "nodes": {
+    "flake-compat": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1696426674,
+        "narHash": "sha256-kvjfFW7WAETZlt09AgDn1MrtKzP7t90Vf7vypd3OL1U=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "0f9255e01c2351cc7d116c072cb317785dd33b33",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
     "flake-utils": {
       "inputs": {
         "systems": "systems"
@@ -18,13 +34,52 @@
         "type": "github"
       }
     },
+    "flake-utils_2": {
+      "inputs": {
+        "systems": "systems_2"
+      },
+      "locked": {
+        "lastModified": 1705309234,
+        "narHash": "sha256-uNRRNRKmJyCRC/8y1RqBkqWBLM034y4qN7EprSdmgyA=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "1ef2e671c3b0c19053962c07dbda38332dcebf26",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "gitignore": {
+      "inputs": {
+        "nixpkgs": [
+          "zlsPkg",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1709087332,
+        "narHash": "sha256-HG2cCnktfHsKV0s4XW83gU3F57gaTljL9KNSuG6bnQs=",
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "rev": "637db329424fd7e46cf4185293b9cc8c88c95394",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1748964450,
-        "narHash": "sha256-ZouDiXkUk8mkMnah10QcoQ9Nu6UW6AFAHLScS3En6aI=",
+        "lastModified": 1756822655,
+        "narHash": "sha256-xQAk8xLy7srAkR5NMZFsQFioL02iTHuuEIs3ohGpgdk=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "9ff500cd9e123f46c55855eca64beccead29b152",
+        "rev": "4bdac60bfe32c41103ae500ddf894c258291dd61",
         "type": "github"
       },
       "original": {
@@ -37,7 +92,9 @@
     "root": {
       "inputs": {
         "flake-utils": "flake-utils",
-        "nixpkgs": "nixpkgs"
+        "nixpkgs": "nixpkgs",
+        "zigPkgs": "zigPkgs",
+        "zlsPkg": "zlsPkg"
       }
     },
     "systems": {
@@ -54,6 +111,68 @@
         "repo": "default",
         "type": "github"
       }
+    },
+    "systems_2": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "zigPkgs": {
+      "inputs": {
+        "flake-compat": "flake-compat",
+        "flake-utils": "flake-utils_2",
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1756555914,
+        "narHash": "sha256-7yoSPIVEuL+3Wzf6e7NHuW3zmruHizRrYhGerjRHTLI=",
+        "owner": "mitchellh",
+        "repo": "zig-overlay",
+        "rev": "d0df3a2fd0f11134409d6d5ea0e510e5e477f7d6",
+        "type": "github"
+      },
+      "original": {
+        "owner": "mitchellh",
+        "repo": "zig-overlay",
+        "type": "github"
+      }
+    },
+    "zlsPkg": {
+      "inputs": {
+        "gitignore": "gitignore",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "zig-overlay": [
+          "zigPkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1756048867,
+        "narHash": "sha256-GFzSHUljcxy7sM1PaabbkQUdUnLwpherekPWJFxXtnk=",
+        "owner": "zigtools",
+        "repo": "zls",
+        "rev": "ce6c8f02c78e622421cfc2405c67c5222819ec03",
+        "type": "github"
+      },
+      "original": {
+        "owner": "zigtools",
+        "ref": "0.15.0",
+        "repo": "zls",
+        "type": "github"
+      }
     }
   },
   "root": "root",

flake.nix

@@ -3,20 +3,37 @@
 
   inputs = {
     nixpkgs.url = "github:nixos/nixpkgs/release-25.05";
+
+    zigPkgs.url = "github:mitchellh/zig-overlay";
+    zigPkgs.inputs.nixpkgs.follows = "nixpkgs";
+
+    zlsPkg.url = "github:zigtools/zls/0.15.0";
+    zlsPkg.inputs.zig-overlay.follows = "zigPkgs";
+    zlsPkg.inputs.nixpkgs.follows = "nixpkgs";
+
     flake-utils.url = "github:numtide/flake-utils";
   };
 
   outputs =
     {
       nixpkgs,
+      zigPkgs,
+      zlsPkg,
       flake-utils,
       ...
     }:
     flake-utils.lib.eachDefaultSystem (
       system:
       let
+        overlays = [
+          (final: prev: {
+            zigpkgs = zigPkgs.packages.${prev.system};
+            zls = zlsPkg.packages.${prev.system}.default;
+          })
+        ];
+
         pkgs = import nixpkgs {
-          inherit system;
+          inherit system overlays;
         };
 
         # We need crtbeginS.o for building.
@@ -32,7 +49,7 @@
           targetPkgs =
             pkgs: with pkgs; [
               # Build Tools
-              zig
+              zigpkgs."0.15.1"
               zls
               python3
               pkg-config
@@ -49,6 +66,7 @@
               glib.dev
               glibc.dev
               zlib
+              zlib.dev
             ];
         };
       in

src/TestHTTPServer.zig

@@ -0,0 +1,117 @@
+const std = @import("std");
+
+const TestHTTPServer = @This();
+
+shutdown: bool,
+listener: ?std.net.Server,
+handler: Handler,
+
+const Handler = *const fn (req: *std.http.Server.Request) anyerror!void;
+
+pub fn init(handler: Handler) TestHTTPServer {
+    return .{
+        .shutdown = true,
+        .listener = null,
+        .handler = handler,
+    };
+}
+
+pub fn deinit(self: *TestHTTPServer) void {
+    self.shutdown = true;
+    if (self.listener) |*listener| {
+        listener.deinit();
+    }
+}
+
+pub fn run(self: *TestHTTPServer, wg: *std.Thread.WaitGroup) !void {
+    const address = try std.net.Address.parseIp("127.0.0.1", 9582);
+
+    self.listener = try address.listen(.{ .reuse_address = true });
+    var listener = &self.listener.?;
+
+    wg.finish();
+
+    while (true) {
+        const conn = listener.accept() catch |err| {
+            if (self.shutdown) {
+                return;
+            }
+            return err;
+        };
+        const thrd = try std.Thread.spawn(.{}, handleConnection, .{ self, conn });
+        thrd.detach();
+    }
+}
+
+fn handleConnection(self: *TestHTTPServer, conn: std.net.Server.Connection) !void {
+    defer conn.stream.close();
+
+    var req_buf: [2048]u8 = undefined;
+    var conn_reader = conn.stream.reader(&req_buf);
+    var conn_writer = conn.stream.writer(&req_buf);
+
+    var http_server = std.http.Server.init(conn_reader.interface(), &conn_writer.interface);
+
+    while (true) {
+        var req = http_server.receiveHead() catch |err| switch (err) {
+            error.ReadFailed => continue,
+            error.HttpConnectionClosing => continue,
+            else => {
+                std.debug.print("Test HTTP Server error: {}\n", .{err});
+                return err;
+            },
+        };
+        self.handler(&req) catch |err| {
+            std.debug.print("test http error '{s}': {}\n", .{ req.head.target, err });
+            try req.respond("server error", .{ .status = .internal_server_error });
+            return;
+        };
+    }
+}
+
+pub fn sendFile(req: *std.http.Server.Request, file_path: []const u8) !void {
+    var file = std.fs.cwd().openFile(file_path, .{}) catch |err| switch (err) {
+        error.FileNotFound => return req.respond("server error", .{ .status = .not_found }),
+        else => return err,
+    };
+
+    const stat = try file.stat();
+    var send_buffer: [4096]u8 = undefined;
+
+    var res = try req.respondStreaming(&send_buffer, .{
+        .content_length = stat.size,
+        .respond_options = .{
+            .extra_headers = &.{
+                .{ .name = "content-type", .value = getContentType(file_path) },
+            },
+        },
+    });
+
+    var read_buffer: [4096]u8 = undefined;
+    var reader = file.reader(&read_buffer);
+    _ = try res.writer.sendFileAll(&reader, .unlimited);
+    try res.writer.flush();
+    try res.end();
+}
+
+fn getContentType(file_path: []const u8) []const u8 {
+    if (std.mem.endsWith(u8, file_path, ".js")) {
+        return "application/json";
+    }
+
+    if (std.mem.endsWith(u8, file_path, ".html")) {
+        return "text/html";
+    }
+
+    if (std.mem.endsWith(u8, file_path, ".htm")) {
+        return "text/html";
+    }
+
+    if (std.mem.endsWith(u8, file_path, ".xml")) {
+        // some wpt tests do this
+        return "text/xml";
+    }
+
+    std.debug.print("TestHTTPServer asked to serve an unknown file type: {s}\n", .{file_path});
+    return "text/html";
+}

src/app.zig

@@ -1,20 +1,22 @@
 const std = @import("std");
+
 const Allocator = std.mem.Allocator;
 
 const log = @import("log.zig");
-const Loop = @import("runtime/loop.zig").Loop;
-const HttpClient = @import("http/client.zig").Client;
+const Http = @import("http/Http.zig");
+const Platform = @import("runtime/js.zig").Platform;
+
 const Telemetry = @import("telemetry/telemetry.zig").Telemetry;
 const Notification = @import("notification.zig").Notification;
 
 // Container for global state / objects that various parts of the system
 // might need.
 pub const App = struct {
-    loop: *Loop,
+    http: Http,
     config: Config,
+    platform: Platform,
     allocator: Allocator,
     telemetry: Telemetry,
-    http_client: HttpClient,
     app_dir_path: ?[]const u8,
     notification: *Notification,
 
@@ -28,38 +30,50 @@ pub const App = struct {
     pub const Config = struct {
         run_mode: RunMode,
         tls_verify_host: bool = true,
-        http_proxy: ?std.Uri = null,
+        http_proxy: ?[:0]const u8 = null,
+        proxy_bearer_token: ?[:0]const u8 = null,
+        http_timeout_ms: ?u31 = null,
+        http_connect_timeout_ms: ?u31 = null,
+        http_max_host_open: ?u8 = null,
+        http_max_concurrent: ?u8 = null,
     };
 
     pub fn init(allocator: Allocator, config: Config) !*App {
         const app = try allocator.create(App);
         errdefer allocator.destroy(app);
 
-        const loop = try allocator.create(Loop);
-        errdefer allocator.destroy(loop);
-
-        loop.* = try Loop.init(allocator);
-        errdefer loop.deinit();
-
         const notification = try Notification.init(allocator, null);
         errdefer notification.deinit();
 
+        var http = try Http.init(allocator, .{
+            .max_host_open = config.http_max_host_open orelse 4,
+            .max_concurrent = config.http_max_concurrent orelse 10,
+            .timeout_ms = config.http_timeout_ms orelse 5000,
+            .connect_timeout_ms = config.http_connect_timeout_ms orelse 0,
+            .http_proxy = config.http_proxy,
+            .tls_verify_host = config.tls_verify_host,
+            .proxy_bearer_token = config.proxy_bearer_token,
+        });
+        errdefer http.deinit();
+
+        const platform = try Platform.init();
+        errdefer platform.deinit();
+
         const app_dir_path = getAndMakeAppDir(allocator);
 
         app.* = .{
-            .loop = loop,
+            .http = http,
             .allocator = allocator,
             .telemetry = undefined,
+            .platform = platform,
             .app_dir_path = app_dir_path,
             .notification = notification,
-            .http_client = try HttpClient.init(allocator, .{
-                .max_concurrent = 3,
-                .http_proxy = config.http_proxy,
-                .tls_verify_host = config.tls_verify_host,
-            }),
             .config = config,
         };
-        app.telemetry = Telemetry.init(app, config.run_mode);
+
+        app.telemetry = try Telemetry.init(app, config.run_mode);
+        errdefer app.telemetry.deinit();
+
         try app.telemetry.register(app.notification);
 
         return app;
@@ -71,10 +85,9 @@ pub const App = struct {
             allocator.free(app_dir_path);
         }
         self.telemetry.deinit();
-        self.loop.deinit();
-        allocator.destroy(self.loop);
-        self.http_client.deinit();
         self.notification.deinit();
+        self.http.deinit();
+        self.platform.deinit();
         allocator.destroy(self);
     }
 };

src/browser/DataURI.zig

@@ -0,0 +1,52 @@
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+
+// Parses data:[<media-type>][;base64],<data>
+pub fn parse(allocator: Allocator, src: []const u8) !?[]const u8 {
+    if (!std.mem.startsWith(u8, src, "data:")) {
+        return null;
+    }
+
+    const uri = src[5..];
+    const data_starts = std.mem.indexOfScalar(u8, uri, ',') orelse return null;
+
+    var data = uri[data_starts + 1 ..];
+
+    // Extract the encoding.
+    const metadata = uri[0..data_starts];
+    if (std.mem.endsWith(u8, metadata, ";base64")) {
+        const decoder = std.base64.standard.Decoder;
+        const decoded_size = try decoder.calcSizeForSlice(data);
+
+        const buffer = try allocator.alloc(u8, decoded_size);
+        errdefer allocator.free(buffer);
+
+        try decoder.decode(buffer, data);
+        data = buffer;
+    }
+
+    return data;
+}
+
+const testing = @import("../testing.zig");
+test "DataURI: parse valid" {
+    try test_valid("data:text/javascript; charset=utf-8;base64,Zm9v", "foo");
+    try test_valid("data:text/javascript; charset=utf-8;,foo", "foo");
+    try test_valid("data:,foo", "foo");
+}
+
+test "DataURI: parse invalid" {
+    try test_cannot_parse("atad:,foo");
+    try test_cannot_parse("data:foo");
+    try test_cannot_parse("data:");
+}
+
+fn test_valid(uri: []const u8, expected: []const u8) !void {
+    defer testing.reset();
+    const data_uri = try parse(testing.arena_allocator, uri) orelse return error.TestFailed;
+    try testing.expectEqual(expected, data_uri);
+}
+
+fn test_cannot_parse(uri: []const u8) !void {
+    try testing.expectEqual(null, parse(undefined, uri));
+}

src/browser/Scheduler.zig

@@ -0,0 +1,174 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+const log = @import("../log.zig");
+const Allocator = std.mem.Allocator;
+
+const Scheduler = @This();
+
+high_priority: Queue,
+
+// For repeating tasks. We only want to run these if there are other things to
+// do. We don't, for example, want a window.setInterval or the page.runMicrotasks
+// to block the page.wait.
+low_priority: Queue,
+
+// we expect allocator to be the page arena, hence we never call high_priority.deinit
+pub fn init(allocator: Allocator) Scheduler {
+    return .{
+        .high_priority = Queue.init(allocator, {}),
+        .low_priority = Queue.init(allocator, {}),
+    };
+}
+
+pub fn reset(self: *Scheduler) void {
+    self.high_priority.clearRetainingCapacity();
+    self.low_priority.clearRetainingCapacity();
+}
+
+const AddOpts = struct {
+    name: []const u8 = "",
+    low_priority: bool = false,
+};
+pub fn add(self: *Scheduler, ctx: *anyopaque, func: Task.Func, ms: u32, opts: AddOpts) !void {
+    var low_priority = opts.low_priority;
+    if (ms > 5_000) {
+        // we don't want tasks in the far future to block page.wait from
+        // completing. However, if page.wait is called multiple times (maybe
+        // a CDP driver is wait for something to happen), then we do want
+        // to [eventually] run these when their time is up.
+        low_priority = true;
+    }
+
+    var q = if (low_priority) &self.low_priority else &self.high_priority;
+    return q.add(.{
+        .ms = std.time.milliTimestamp() + ms,
+        .ctx = ctx,
+        .func = func,
+        .name = opts.name,
+    });
+}
+
+pub fn runHighPriority(self: *Scheduler) !?i32 {
+    return self.runQueue(&self.high_priority);
+}
+
+pub fn runLowPriority(self: *Scheduler) !?i32 {
+    return self.runQueue(&self.low_priority);
+}
+
+fn runQueue(self: *Scheduler, queue: *Queue) !?i32 {
+    // this is O(1)
+    if (queue.count() == 0) {
+        return null;
+    }
+
+    const now = std.time.milliTimestamp();
+
+    var next = queue.peek();
+    while (next) |task| {
+        const time_to_next = task.ms - now;
+        if (time_to_next > 0) {
+            // @intCast is petty safe since we limit tasks to just 5 seconds
+            // in the future
+            return @intCast(time_to_next);
+        }
+
+        if (task.func(task.ctx)) |repeat_delay| {
+            // if we do (now + 0) then our WHILE loop will run endlessly.
+            // no task should ever return 0
+            std.debug.assert(repeat_delay != 0);
+
+            var copy = task;
+            copy.ms = now + repeat_delay;
+            try self.low_priority.add(copy);
+        }
+        _ = queue.remove();
+        next = queue.peek();
+    }
+    return null;
+}
+
+const Task = struct {
+    ms: i64,
+    func: Func,
+    ctx: *anyopaque,
+    name: []const u8,
+
+    const Func = *const fn (ctx: *anyopaque) ?u32;
+};
+
+const Queue = std.PriorityQueue(Task, void, struct {
+    fn compare(_: void, a: Task, b: Task) std.math.Order {
+        return std.math.order(a.ms, b.ms);
+    }
+}.compare);
+
+const testing = @import("../testing.zig");
+test "Scheduler" {
+    defer testing.reset();
+
+    var task = TestTask{ .allocator = testing.arena_allocator };
+
+    var s = Scheduler.init(testing.arena_allocator);
+    try testing.expectEqual(null, s.runHighPriority());
+    try testing.expectEqual(0, task.calls.items.len);
+
+    try s.add(&task, TestTask.run1, 3, .{});
+
+    try testing.expectDelta(3, try s.runHighPriority(), 1);
+    try testing.expectEqual(0, task.calls.items.len);
+
+    std.Thread.sleep(std.time.ns_per_ms * 5);
+    try testing.expectEqual(null, s.runHighPriority());
+    try testing.expectEqualSlices(u32, &.{1}, task.calls.items);
+
+    try s.add(&task, TestTask.run2, 3, .{});
+    try s.add(&task, TestTask.run1, 2, .{});
+
+    std.Thread.sleep(std.time.ns_per_ms * 5);
+    try testing.expectDelta(null, try s.runHighPriority(), 1);
+    try testing.expectEqualSlices(u32, &.{ 1, 1, 2 }, task.calls.items);
+
+    std.Thread.sleep(std.time.ns_per_ms * 5);
+    // won't run low_priority
+    try testing.expectEqual(null, try s.runHighPriority());
+    try testing.expectEqualSlices(u32, &.{ 1, 1, 2 }, task.calls.items);
+
+    //runs low_priority
+    try testing.expectDelta(2, try s.runLowPriority(), 1);
+    try testing.expectEqualSlices(u32, &.{ 1, 1, 2, 2 }, task.calls.items);
+}
+
+const TestTask = struct {
+    allocator: Allocator,
+    calls: std.ArrayListUnmanaged(u32) = .{},
+
+    fn run1(ctx: *anyopaque) ?u32 {
+        var self: *TestTask = @ptrCast(@alignCast(ctx));
+        self.calls.append(self.allocator, 1) catch unreachable;
+        return null;
+    }
+
+    fn run2(ctx: *anyopaque) ?u32 {
+        var self: *TestTask = @ptrCast(@alignCast(ctx));
+        self.calls.append(self.allocator, 2) catch unreachable;
+        return 2;
+    }
+};

src/browser/ScriptManager.zig

@@ -0,0 +1,835 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const log = @import("../log.zig");
+const parser = @import("netsurf.zig");
+
+const Env = @import("env.zig").Env;
+const Page = @import("page.zig").Page;
+const DataURI = @import("DataURI.zig");
+const Http = @import("../http/Http.zig");
+const Browser = @import("browser.zig").Browser;
+const URL = @import("../url.zig").URL;
+
+const Allocator = std.mem.Allocator;
+const ArrayListUnmanaged = std.ArrayListUnmanaged;
+
+const ScriptManager = @This();
+
+page: *Page,
+
+// used to prevent recursive evalutaion
+is_evaluating: bool,
+
+// used to prevent executing scripts while we're doing a blocking load
+is_blocking: bool = false,
+
+// Only once this is true can deferred scripts be run
+static_scripts_done: bool,
+
+// List of async scripts. We don't care about the execution order of these, but
+// on shutdown/abort, we need to cleanup any pending ones.
+asyncs: OrderList,
+
+// When an async script is ready to be evaluated, it's moved from asyncs to
+// this list. You might think we can evaluate an async script as soon as it's
+// done, but we can only evaluate scripts when `is_blocking == false`. So this
+// becomes a list of scripts to execute on the next evaluate().
+asyncs_ready: OrderList,
+
+// Normal scripts (non-deferred & non-async). These must be executed in order
+scripts: OrderList,
+
+// List of deferred scripts. These must be executed in order, but only once
+// dom_loaded == true,
+deferreds: OrderList,
+
+shutdown: bool = false,
+
+client: *Http.Client,
+allocator: Allocator,
+buffer_pool: BufferPool,
+script_pool: std.heap.MemoryPool(PendingScript),
+
+const OrderList = std.DoublyLinkedList;
+
+pub fn init(browser: *Browser, page: *Page) ScriptManager {
+    // page isn't fully initialized, we can setup our reference, but that's it.
+    const allocator = browser.allocator;
+    return .{
+        .page = page,
+        .asyncs = .{},
+        .scripts = .{},
+        .deferreds = .{},
+        .asyncs_ready = .{},
+        .is_evaluating = false,
+        .allocator = allocator,
+        .client = browser.http_client,
+        .static_scripts_done = false,
+        .buffer_pool = BufferPool.init(allocator, 5),
+        .script_pool = std.heap.MemoryPool(PendingScript).init(allocator),
+    };
+}
+
+pub fn deinit(self: *ScriptManager) void {
+    self.reset();
+    self.buffer_pool.deinit();
+    self.script_pool.deinit();
+}
+
+pub fn reset(self: *ScriptManager) void {
+    self.clearList(&self.asyncs);
+    self.clearList(&self.scripts);
+    self.clearList(&self.deferreds);
+    self.clearList(&self.asyncs_ready);
+    self.static_scripts_done = false;
+}
+
+fn clearList(_: *const ScriptManager, list: *OrderList) void {
+    while (list.first) |node| {
+        const pending_script: *PendingScript = @fieldParentPtr("node", node);
+        // this removes it from the list
+        pending_script.deinit();
+    }
+    std.debug.assert(list.first == null);
+}
+
+pub fn addFromElement(self: *ScriptManager, element: *parser.Element) !void {
+    if (try parser.elementGetAttribute(element, "nomodule") != null) {
+        // these scripts should only be loaded if we don't support modules
+        // but since we do support modules, we can just skip them.
+        return;
+    }
+
+    // If a script tag gets dynamically created and added to the dom:
+    //    document.getElementsByTagName('head')[0].appendChild(script)
+    // that script tag will immediately get executed by our scriptAddedCallback.
+    // However, if the location where the script tag is inserted happens to be
+    // below where processHTMLDoc currently is, then we'll re-run that same script
+    // again in processHTMLDoc. This flag is used to let us know if a specific
+    // <script> has already been processed.
+    if (try parser.scriptGetProcessed(@ptrCast(element))) {
+        return;
+    }
+    try parser.scriptSetProcessed(@ptrCast(element), true);
+
+    const kind: Script.Kind = blk: {
+        const script_type = try parser.elementGetAttribute(element, "type") orelse break :blk .javascript;
+        if (script_type.len == 0) {
+            break :blk .javascript;
+        }
+        if (std.ascii.eqlIgnoreCase(script_type, "application/javascript")) {
+            break :blk .javascript;
+        }
+        if (std.ascii.eqlIgnoreCase(script_type, "text/javascript")) {
+            break :blk .javascript;
+        }
+        if (std.ascii.eqlIgnoreCase(script_type, "module")) {
+            break :blk .module;
+        }
+
+        // "type" could be anything, but only the above are ones we need to process.
+        // Common other ones are application/json, application/ld+json, text/template
+
+        return;
+    };
+
+    const page = self.page;
+    var source: Script.Source = undefined;
+    var remote_url: ?[:0]const u8 = null;
+    if (try parser.elementGetAttribute(element, "src")) |src| {
+        if (try DataURI.parse(page.arena, src)) |data_uri| {
+            source = .{ .@"inline" = data_uri };
+        }
+        remote_url = try URL.stitch(page.arena, src, page.url.raw, .{ .null_terminated = true });
+        source = .{ .remote = .{} };
+    } else {
+        const inline_source = try parser.nodeTextContent(@ptrCast(element)) orelse return;
+        source = .{ .@"inline" = inline_source };
+    }
+
+    var script = Script{
+        .kind = kind,
+        .element = element,
+        .source = source,
+        .url = remote_url orelse page.url.raw,
+        .is_defer = if (remote_url == null) false else try parser.elementGetAttribute(element, "defer") != null,
+        .is_async = if (remote_url == null) false else try parser.elementGetAttribute(element, "async") != null,
+    };
+
+    if (source == .@"inline" and self.scripts.first == null) {
+        // inline script with no pending scripts, execute it immediately.
+        // (if there is a pending script, then we cannot execute this immediately
+        // as it needs to best executed in order)
+        return script.eval(page);
+    }
+
+    const pending_script = try self.script_pool.create();
+    errdefer self.script_pool.destroy(pending_script);
+    pending_script.* = .{
+        .script = script,
+        .complete = false,
+        .manager = self,
+        .node = .{},
+    };
+
+    if (source == .@"inline") {
+        // if we're here, it means that we have pending scripts (i.e. self.scripts
+        // is not empty). Because the script is inline, it's complete/ready, but
+        // we need to process them in order
+        pending_script.complete = true;
+        self.scripts.append(&pending_script.node);
+        return;
+    } else {
+        log.debug(.http, "script queue", .{ .url = remote_url.? });
+    }
+
+    pending_script.getList().append(&pending_script.node);
+
+    errdefer pending_script.deinit();
+
+    var headers = try Http.Headers.init();
+    try page.requestCookie(.{}).headersForRequest(page.arena, remote_url.?, &headers);
+
+    try self.client.request(.{
+        .url = remote_url.?,
+        .ctx = pending_script,
+        .method = .GET,
+        .headers = headers,
+        .cookie_jar = page.cookie_jar,
+        .resource_type = .script,
+        .start_callback = if (log.enabled(.http, .debug)) startCallback else null,
+        .header_callback = headerCallback,
+        .data_callback = dataCallback,
+        .done_callback = doneCallback,
+        .error_callback = errorCallback,
+    });
+}
+
+// @TODO: Improving this would have the simplest biggest performance improvement
+// for most sites.
+//
+// For JS imports (both static and dynamic), we currently block to get the
+// result (the content of the file).
+//
+// For static imports, this is necessary, since v8 is expecting the compiled module
+// as part of the function return. (we should try to pre-load the JavaScript
+// source via module.GetModuleRequests(), but that's for a later time).
+//
+// For dynamic dynamic imports, this is not strictly necessary since the v8
+// call returns a Promise; we could make this a normal get call, associated with
+// the promise, and when done, resolve the promise.
+//
+// In both cases, for now at least, we just issue a "blocking" request. We block
+// by ticking the http client until the script is complete.
+//
+// This uses the client.blockingRequest call which has a dedicated handle for
+// these blocking requests. Because they are blocking, we're guaranteed to have
+// only 1 at a time, thus the 1 reserved handle.
+//
+// You almost don't need the http client's blocking handle. In most cases, you
+// should always have 1 free handle whenever you get here, because we always
+// release the handle before executing the doneCallback. So, if a module does:
+//    import * as x from 'blah'
+// And we need to load 'blah', there should always be 1 free handle - the handle
+// of the http GET we just completed before executing the module.
+// The exception to this, and the reason we need a special blocking handle, is
+// for inline modules within the HTML page itself:
+//    <script type=module>import ....</script>
+// Unlike external modules which can only ever be executed after releasing an
+// http handle, these are executed without there necessarily being a free handle.
+// Thus, Http/Client.zig maintains a dedicated handle for these calls.
+pub fn blockingGet(self: *ScriptManager, url: [:0]const u8) !BlockingResult {
+    std.debug.assert(self.is_blocking == false);
+
+    self.is_blocking = true;
+    defer {
+        self.is_blocking = false;
+
+        // we blocked evaluation while loading this script, there could be
+        // scripts ready to process.
+        self.evaluate();
+    }
+
+    var blocking = Blocking{
+        .allocator = self.allocator,
+        .buffer_pool = &self.buffer_pool,
+    };
+
+    var headers = try Http.Headers.init();
+    try self.page.requestCookie(.{}).headersForRequest(self.page.arena, url, &headers);
+
+    var client = self.client;
+    try client.blockingRequest(.{
+        .url = url,
+        .method = .GET,
+        .headers = headers,
+        .cookie_jar = self.page.cookie_jar,
+        .ctx = &blocking,
+        .resource_type = .script,
+        .start_callback = if (log.enabled(.http, .debug)) Blocking.startCallback else null,
+        .header_callback = Blocking.headerCallback,
+        .data_callback = Blocking.dataCallback,
+        .done_callback = Blocking.doneCallback,
+        .error_callback = Blocking.errorCallback,
+    });
+
+    // rely on http's timeout settings to avoid an endless/long loop.
+    while (true) {
+        _ = try client.tick(200);
+        switch (blocking.state) {
+            .running => {},
+            .done => |result| return result,
+            .err => |err| return err,
+        }
+    }
+}
+
+pub fn staticScriptsDone(self: *ScriptManager) void {
+    std.debug.assert(self.static_scripts_done == false);
+    self.static_scripts_done = true;
+}
+
+// try to evaluate completed scripts (in order). This is called whenever a script
+// is completed.
+fn evaluate(self: *ScriptManager) void {
+    if (self.is_evaluating) {
+        // It's possible for a script.eval to cause evaluate to be called again.
+        // This is particularly true with blockingGet, but even without this,
+        // it's theoretically possible (but unlikely). We could make this work
+        // but there's little reason to support the complexity.
+        return;
+    }
+
+    if (self.is_blocking) {
+        // Cannot evaluate scripts while a blocking-load is in progress. Not
+        // only could that result in incorrect evaluation order, it could
+        // trigger another blocking request, while we're doing a blocking request.
+        return;
+    }
+
+    const page = self.page;
+    self.is_evaluating = true;
+    defer self.is_evaluating = false;
+
+    // every script in asyncs_ready is ready to be evaluated.
+    while (self.asyncs_ready.first) |n| {
+        var pending_script: *PendingScript = @fieldParentPtr("node", n);
+        defer pending_script.deinit();
+        pending_script.script.eval(page);
+    }
+
+    while (self.scripts.first) |n| {
+        var pending_script: *PendingScript = @fieldParentPtr("node", n);
+        if (pending_script.complete == false) {
+            return;
+        }
+        defer pending_script.deinit();
+        pending_script.script.eval(page);
+    }
+
+    if (self.static_scripts_done == false) {
+        // We can only execute deferred scripts if
+        // 1 - all the normal scripts are done
+        // 2 - we've finished parsing the HTML and at least queued all the scripts
+        // The last one isn't obvious, but it's possible for self.scripts to
+        // be empty not because we're done executing all the normal scripts
+        // but because we're done executing some (or maybe none), but we're still
+        // parsing the HTML.
+        return;
+    }
+
+    while (self.deferreds.first) |n| {
+        var pending_script: *PendingScript = @fieldParentPtr("node", n);
+        if (pending_script.complete == false) {
+            return;
+        }
+        defer pending_script.deinit();
+        pending_script.script.eval(page);
+    }
+
+    // When all scripts (normal and deferred) are done loading, the document
+    // state changes (this ultimately triggers the DOMContentLoaded event)
+    page.documentIsLoaded();
+
+    if (self.asyncs.first == null) {
+        // 1 - there are no async scripts pending
+        // 2 - we checkecked static_scripts_done == true above
+        // 3 - we drained self.scripts above
+        // 4 - we drained self.deferred above
+        page.documentIsComplete();
+    }
+}
+
+pub fn isDone(self: *const ScriptManager) bool {
+    return self.asyncs.first == null and // there are no more async scripts
+        self.static_scripts_done and // and we've finished parsing the HTML to queue all <scripts>
+        self.scripts.first == null and // and there are no more <script src=> to wait for
+        self.deferreds.first == null; // and there are no more <script defer src=> to wait for
+}
+
+fn startCallback(transfer: *Http.Transfer) !void {
+    const script: *PendingScript = @ptrCast(@alignCast(transfer.ctx));
+    script.startCallback(transfer) catch |err| {
+        log.err(.http, "SM.startCallback", .{ .err = err, .transfer = transfer });
+        return err;
+    };
+}
+
+fn headerCallback(transfer: *Http.Transfer) !void {
+    const script: *PendingScript = @ptrCast(@alignCast(transfer.ctx));
+    try script.headerCallback(transfer);
+}
+
+fn dataCallback(transfer: *Http.Transfer, data: []const u8) !void {
+    const script: *PendingScript = @ptrCast(@alignCast(transfer.ctx));
+    script.dataCallback(transfer, data) catch |err| {
+        log.err(.http, "SM.dataCallback", .{ .err = err, .transfer = transfer, .len = data.len });
+        return err;
+    };
+}
+
+fn doneCallback(ctx: *anyopaque) !void {
+    const script: *PendingScript = @ptrCast(@alignCast(ctx));
+    script.doneCallback();
+}
+
+fn errorCallback(ctx: *anyopaque, err: anyerror) void {
+    const script: *PendingScript = @ptrCast(@alignCast(ctx));
+    script.errorCallback(err);
+}
+
+// A script which is pending execution.
+// It could be pending because:
+//   (a) we're still downloading its content or
+//   (b) this is a non-async script that has to be executed in order
+pub const PendingScript = struct {
+    script: Script,
+    complete: bool,
+    node: OrderList.Node,
+    manager: *ScriptManager,
+
+    fn deinit(self: *PendingScript) void {
+        const script = &self.script;
+        const manager = self.manager;
+
+        if (script.source == .remote) {
+            manager.buffer_pool.release(script.source.remote);
+        }
+        self.getList().remove(&self.node);
+    }
+
+    fn remove(self: *PendingScript) void {
+        if (self.node) |*node| {
+            self.getList().remove(node);
+            self.node = null;
+        }
+    }
+
+    fn startCallback(self: *PendingScript, transfer: *Http.Transfer) !void {
+        _ = self;
+        log.debug(.http, "script fetch start", .{ .req = transfer });
+    }
+
+    fn headerCallback(self: *PendingScript, transfer: *Http.Transfer) !void {
+        const header = &transfer.response_header.?;
+        if (header.status != 200) {
+            log.info(.http, "script header", .{
+                .req = transfer,
+                .status = header.status,
+                .content_type = header.contentType(),
+            });
+            return;
+        }
+
+        log.debug(.http, "script header", .{
+            .req = transfer,
+            .status = header.status,
+            .content_type = header.contentType(),
+        });
+
+        // If this isn't true, then we'll likely leak memory. If you don't
+        // set `CURLOPT_SUPPRESS_CONNECT_HEADERS` and CONNECT to a proxy, this
+        // will fail. This assertion exists to catch incorrect assumptions about
+        // how libcurl works, or about how we've configured it.
+        std.debug.assert(self.script.source.remote.capacity == 0);
+        var buffer = self.manager.buffer_pool.get();
+        if (transfer.getContentLength()) |cl| {
+            try buffer.ensureTotalCapacity(self.manager.allocator, cl);
+        }
+        self.script.source = .{ .remote = buffer };
+    }
+
+    fn dataCallback(self: *PendingScript, transfer: *Http.Transfer, data: []const u8) !void {
+        _ = transfer;
+        // too verbose
+        // log.debug(.http, "script data chunk", .{
+        //     .req = transfer,
+        //     .len = data.len,
+        // });
+
+        try self.script.source.remote.appendSlice(self.manager.allocator, data);
+    }
+
+    fn doneCallback(self: *PendingScript) void {
+        log.debug(.http, "script fetch complete", .{ .req = self.script.url });
+
+        const manager = self.manager;
+        self.complete = true;
+        if (self.script.is_async) {
+            manager.asyncs.remove(&self.node);
+            manager.asyncs_ready.append(&self.node);
+        }
+        manager.evaluate();
+    }
+
+    fn errorCallback(self: *PendingScript, err: anyerror) void {
+        log.warn(.http, "script fetch error", .{ .req = self.script.url, .err = err });
+
+        const manager = self.manager;
+
+        self.deinit();
+
+        if (manager.shutdown) {
+            return;
+        }
+
+        manager.evaluate();
+    }
+
+    fn getList(self: *const PendingScript) *OrderList {
+        // When a script has both the async and defer flag set, it should be
+        // treated as async. Async is newer, so some websites use both so that
+        // if async isn't known, it'll fallback to defer.
+
+        const script = &self.script;
+        if (script.is_async) {
+            return if (self.complete) &self.manager.asyncs_ready else &self.manager.asyncs;
+        }
+
+        if (script.is_defer) {
+            return &self.manager.deferreds;
+        }
+
+        return &self.manager.scripts;
+    }
+};
+
+const Script = struct {
+    kind: Kind,
+    url: []const u8,
+    is_async: bool,
+    is_defer: bool,
+    source: Source,
+    element: *parser.Element,
+
+    const Kind = enum {
+        module,
+        javascript,
+    };
+
+    const Callback = union(enum) {
+        string: []const u8,
+        function: Env.Function,
+    };
+
+    const Source = union(enum) {
+        @"inline": []const u8,
+        remote: std.ArrayListUnmanaged(u8),
+
+        fn content(self: Source) []const u8 {
+            return switch (self) {
+                .remote => |buf| buf.items,
+                .@"inline" => |c| c,
+            };
+        }
+    };
+
+    fn eval(self: *Script, page: *Page) void {
+        page.setCurrentScript(@ptrCast(self.element)) catch |err| {
+            log.err(.browser, "set document script", .{ .err = err });
+            return;
+        };
+
+        defer page.setCurrentScript(null) catch |err| {
+            log.err(.browser, "clear document script", .{ .err = err });
+        };
+
+        // inline scripts aren't cached. remote ones are.
+        const cacheable = self.source == .remote;
+
+        const url = self.url;
+
+        log.info(.browser, "executing script", .{
+            .src = url,
+            .kind = self.kind,
+            .cacheable = cacheable,
+        });
+
+        const js_context = page.main_context;
+        var try_catch: Env.TryCatch = undefined;
+        try_catch.init(js_context);
+        defer try_catch.deinit();
+
+        const success = blk: {
+            const content = self.source.content();
+            switch (self.kind) {
+                .javascript => _ = js_context.eval(content, url) catch break :blk false,
+                .module => {
+                    // We don't care about waiting for the evaluation here.
+                    _ = js_context.module(content, url, cacheable) catch break :blk false;
+                },
+            }
+            break :blk true;
+        };
+
+        if (success) {
+            self.executeCallback("onload", page);
+            return;
+        }
+
+        if (page.delayed_navigation) {
+            // If we're navigating to another page, an error is expected
+            // since we probably terminated the script forcefully.
+            return;
+        }
+
+        const msg = try_catch.err(page.arena) catch |err| @errorName(err) orelse "unknown";
+        log.warn(.user_script, "eval script", .{
+            .url = url,
+            .err = msg,
+            .cacheable = cacheable,
+        });
+
+        self.executeCallback("onerror", page);
+    }
+
+    fn executeCallback(self: *const Script, comptime typ: []const u8, page: *Page) void {
+        const callback = self.getCallback(typ, page) orelse return;
+
+        switch (callback) {
+            .string => |str| {
+                var try_catch: Env.TryCatch = undefined;
+                try_catch.init(page.main_context);
+                defer try_catch.deinit();
+
+                _ = page.main_context.exec(str, typ) catch |err| {
+                    const msg = try_catch.err(page.arena) catch @errorName(err) orelse "unknown";
+                    log.warn(.user_script, "script callback", .{
+                        .url = self.url,
+                        .err = msg,
+                        .type = typ,
+                        .@"inline" = true,
+                    });
+                };
+            },
+            .function => |f| {
+                const Event = @import("events/event.zig").Event;
+                const loadevt = parser.eventCreate() catch |err| {
+                    log.err(.browser, "SM event creation", .{ .err = err });
+                    return;
+                };
+                defer parser.eventDestroy(loadevt);
+
+                var result: Env.Function.Result = undefined;
+                const iface = Event.toInterface(loadevt) catch |err| {
+                    log.err(.browser, "SM event interface", .{ .err = err });
+                    return;
+                };
+                f.tryCall(void, .{iface}, &result) catch {
+                    log.warn(.user_script, "script callback", .{
+                        .url = self.url,
+                        .type = typ,
+                        .err = result.exception,
+                        .stack = result.stack,
+                        .@"inline" = false,
+                    });
+                };
+            },
+        }
+    }
+
+    fn getCallback(self: *const Script, comptime typ: []const u8, page: *Page) ?Callback {
+        const element = self.element;
+        // first we check if there was an el.onload set directly on the
+        // element in JavaScript (if so, it'd be stored in the node state)
+        if (page.getNodeState(@ptrCast(element))) |se| {
+            if (@field(se, typ)) |function| {
+                return .{ .function = function };
+            }
+        }
+        // if we have no node state, or if the node state has no onload/onerror
+        // then check for the onload/onerror attribute
+        if (parser.elementGetAttribute(element, typ) catch null) |string| {
+            return .{ .string = string };
+        }
+        return null;
+    }
+};
+
+const BufferPool = struct {
+    count: usize,
+    available: List = .{},
+    allocator: Allocator,
+    max_concurrent_transfers: u8,
+    mem_pool: std.heap.MemoryPool(Container),
+
+    const List = std.DoublyLinkedList;
+
+    const Container = struct {
+        node: List.Node,
+        buf: std.ArrayListUnmanaged(u8),
+    };
+
+    fn init(allocator: Allocator, max_concurrent_transfers: u8) BufferPool {
+        return .{
+            .available = .{},
+            .count = 0,
+            .allocator = allocator,
+            .max_concurrent_transfers = max_concurrent_transfers,
+            .mem_pool = std.heap.MemoryPool(Container).init(allocator),
+        };
+    }
+
+    fn deinit(self: *BufferPool) void {
+        const allocator = self.allocator;
+
+        var node = self.available.first;
+        while (node) |n| {
+            const container: *Container = @fieldParentPtr("node", n);
+            container.buf.deinit(allocator);
+            node = n.next;
+        }
+        self.mem_pool.deinit();
+    }
+
+    fn get(self: *BufferPool) std.ArrayListUnmanaged(u8) {
+        const node = self.available.popFirst() orelse {
+            // return a new buffer
+            return .{};
+        };
+
+        self.count -= 1;
+        const container: *Container = @fieldParentPtr("node", node);
+        defer self.mem_pool.destroy(container);
+        return container.buf;
+    }
+
+    fn release(self: *BufferPool, buffer: ArrayListUnmanaged(u8)) void {
+        // create mutable copy
+        var b = buffer;
+
+        if (self.count == self.max_concurrent_transfers) {
+            b.deinit(self.allocator);
+            return;
+        }
+
+        const container = self.mem_pool.create() catch |err| {
+            b.deinit(self.allocator);
+            log.err(.http, "SM BufferPool release", .{ .err = err });
+            return;
+        };
+
+        b.clearRetainingCapacity();
+        container.* = .{ .buf = b, .node = .{} };
+        self.count += 1;
+        self.available.append(&container.node);
+    }
+};
+
+const Blocking = struct {
+    allocator: Allocator,
+    buffer_pool: *BufferPool,
+    state: State = .{ .running = {} },
+    buffer: std.ArrayListUnmanaged(u8) = .{},
+
+    const State = union(enum) {
+        running: void,
+        err: anyerror,
+        done: BlockingResult,
+    };
+
+    fn startCallback(transfer: *Http.Transfer) !void {
+        log.debug(.http, "script fetch start", .{ .req = transfer, .blocking = true });
+    }
+
+    fn headerCallback(transfer: *Http.Transfer) !void {
+        const header = &transfer.response_header.?;
+        log.debug(.http, "script header", .{
+            .req = transfer,
+            .blocking = true,
+            .status = header.status,
+            .content_type = header.contentType(),
+        });
+
+        if (header.status != 200) {
+            return error.InvalidStatusCode;
+        }
+
+        var self: *Blocking = @ptrCast(@alignCast(transfer.ctx));
+        self.buffer = self.buffer_pool.get();
+    }
+
+    fn dataCallback(transfer: *Http.Transfer, data: []const u8) !void {
+        // too verbose
+        // log.debug(.http, "script data chunk", .{
+        //     .req = transfer,
+        //     .blocking = true,
+        // });
+
+        var self: *Blocking = @ptrCast(@alignCast(transfer.ctx));
+        self.buffer.appendSlice(self.allocator, data) catch |err| {
+            log.err(.http, "SM.dataCallback", .{
+                .err = err,
+                .len = data.len,
+                .blocking = true,
+                .transfer = transfer,
+            });
+            return err;
+        };
+    }
+
+    fn doneCallback(ctx: *anyopaque) !void {
+        var self: *Blocking = @ptrCast(@alignCast(ctx));
+        self.state = .{ .done = .{
+            .buffer = self.buffer,
+            .buffer_pool = self.buffer_pool,
+        } };
+    }
+
+    fn errorCallback(ctx: *anyopaque, err: anyerror) void {
+        var self: *Blocking = @ptrCast(@alignCast(ctx));
+        self.state = .{ .err = err };
+        self.buffer_pool.release(self.buffer);
+    }
+};
+
+pub const BlockingResult = struct {
+    buffer: std.ArrayListUnmanaged(u8),
+    buffer_pool: *BufferPool,
+
+    pub fn deinit(self: *BlockingResult) void {
+        self.buffer_pool.release(self.buffer);
+    }
+
+    pub fn src(self: *const BlockingResult) []const u8 {
+        return self.buffer.items;
+    }
+};

src/browser/State.zig

@@ -28,7 +28,11 @@
 
 const Env = @import("env.zig").Env;
 const parser = @import("netsurf.zig");
-const CSSStyleDeclaration = @import("cssom/css_style_declaration.zig").CSSStyleDeclaration;
+const DataSet = @import("html/DataSet.zig");
+const ShadowRoot = @import("dom/shadow_root.zig").ShadowRoot;
+const StyleSheet = @import("cssom/StyleSheet.zig");
+const CSSStyleSheet = @import("cssom/CSSStyleSheet.zig");
+const CSSStyleDeclaration = @import("cssom/CSSStyleDeclaration.zig");
 
 // for HTMLScript (but probably needs to be added to more)
 onload: ?Env.Function = null,
@@ -36,12 +40,21 @@ onerror: ?Env.Function = null,
 
 // for HTMLElement
 style: CSSStyleDeclaration = .empty,
+dataset: ?DataSet = null,
+template_content: ?*parser.DocumentFragment = null,
+
+// For dom/element
+shadow_root: ?*ShadowRoot = null,
 
 // for html/document
 ready_state: ReadyState = .loading,
 
+// for html/HTMLStyleElement
+style_sheet: ?*StyleSheet = null,
+
 // for dom/document
 active_element: ?*parser.Element = null,
+adopted_style_sheets: ?Env.JsObject = null,
 
 // for HTMLSelectElement
 // By default, if no option is explicitly selected, the first option should

src/browser/browser.zig

@@ -27,7 +27,8 @@ const App = @import("../app.zig").App;
 const Session = @import("session.zig").Session;
 const Notification = @import("../notification.zig").Notification;
 
-const http = @import("../http/client.zig");
+const log = @import("../log.zig");
+const HttpClient = @import("../http/Client.zig");
 
 // Browser is an instance of the browser.
 // You can create multiple browser instances.
@@ -37,7 +38,7 @@ pub const Browser = struct {
     app: *App,
     session: ?Session,
     allocator: Allocator,
-    http_client: *http.Client,
+    http_client: *HttpClient,
     page_arena: ArenaAllocator,
     session_arena: ArenaAllocator,
     transfer_arena: ArenaAllocator,
@@ -47,10 +48,12 @@ pub const Browser = struct {
     pub fn init(app: *App) !Browser {
         const allocator = app.allocator;
 
-        const env = try Env.init(allocator, .{});
+        const env = try Env.init(allocator, &app.platform, .{});
         errdefer env.deinit();
 
         const notification = try Notification.init(allocator, app.notification);
+        app.http.client.notification = notification;
+        app.http.client.next_request_id = 0; // Should we track ids in CDP only?
         errdefer notification.deinit();
 
         return .{
@@ -59,7 +62,7 @@ pub const Browser = struct {
             .session = null,
             .allocator = allocator,
             .notification = notification,
-            .http_client = &app.http_client,
+            .http_client = app.http.client,
             .page_arena = ArenaAllocator.init(allocator),
             .session_arena = ArenaAllocator.init(allocator),
             .transfer_arena = ArenaAllocator.init(allocator),
@@ -73,6 +76,7 @@ pub const Browser = struct {
         self.page_arena.deinit();
         self.session_arena.deinit();
         self.transfer_arena.deinit();
+        self.http_client.notification = null;
         self.notification.deinit();
         self.state_pool.deinit();
     }
@@ -95,17 +99,18 @@ pub const Browser = struct {
     }
 
     pub fn runMicrotasks(self: *const Browser) void {
-        return self.env.runMicrotasks();
+        self.env.runMicrotasks();
+    }
+
+    pub fn runMessageLoop(self: *const Browser) void {
+        while (self.env.pumpMessageLoop()) {
+            log.debug(.browser, "pumpMessageLoop", .{});
+        }
+        self.env.runIdleTasks();
     }
 };
 
 const testing = @import("../testing.zig");
 test "Browser" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    // this will crash if ICU isn't properly configured / ininitialized
-    try runner.testCases(&.{
-        .{ "new Intl.DateTimeFormat()", "[object Intl.DateTimeFormat]" },
-    }, .{});
+    try testing.htmlRunner("browser.html");
 }

src/browser/console/console.zig

@@ -18,62 +18,61 @@
 
 const std = @import("std");
 const builtin = @import("builtin");
+const log = @import("../../log.zig");
 
 const Allocator = std.mem.Allocator;
 const Page = @import("../page.zig").Page;
 const JsObject = @import("../env.zig").Env.JsObject;
 
-const log = if (builtin.is_test) &test_capture else @import("../../log.zig");
-
 pub const Console = struct {
     // TODO: configurable writer
     timers: std.StringHashMapUnmanaged(u32) = .{},
     counts: std.StringHashMapUnmanaged(u32) = .{},
 
-    pub fn static_lp(values: []JsObject, page: *Page) !void {
+    pub fn _lp(values: []JsObject, page: *Page) !void {
         if (values.len == 0) {
             return;
         }
         log.fatal(.console, "lightpanda", .{ .args = try serializeValues(values, page) });
     }
 
-    pub fn static_log(values: []JsObject, page: *Page) !void {
+    pub fn _log(values: []JsObject, page: *Page) !void {
         if (values.len == 0) {
             return;
         }
         log.info(.console, "info", .{ .args = try serializeValues(values, page) });
     }
 
-    pub fn static_info(values: []JsObject, page: *Page) !void {
-        return static_log(values, page);
+    pub fn _info(values: []JsObject, page: *Page) !void {
+        return _log(values, page);
     }
 
-    pub fn static_debug(values: []JsObject, page: *Page) !void {
+    pub fn _debug(values: []JsObject, page: *Page) !void {
         if (values.len == 0) {
             return;
         }
         log.debug(.console, "debug", .{ .args = try serializeValues(values, page) });
     }
 
-    pub fn static_warn(values: []JsObject, page: *Page) !void {
+    pub fn _warn(values: []JsObject, page: *Page) !void {
         if (values.len == 0) {
             return;
         }
         log.warn(.console, "warn", .{ .args = try serializeValues(values, page) });
     }
 
-    pub fn static_error(values: []JsObject, page: *Page) !void {
+    pub fn _error(values: []JsObject, page: *Page) !void {
         if (values.len == 0) {
             return;
         }
 
-        log.info(.console, "error", .{
+        log.warn(.console, "error", .{
             .args = try serializeValues(values, page),
             .stack = page.stackTrace() catch "???",
         });
     }
 
-    pub fn static_clear() void {}
+    pub fn _clear() void {}
 
     pub fn _count(self: *Console, label_: ?[]const u8, page: *Page) !void {
         const label = label_ orelse "default";
@@ -134,7 +133,7 @@ pub const Console = struct {
         log.warn(.console, "timer stop", .{ .label = label, .elapsed = elapsed - kv.value });
     }
 
-    pub fn static_assert(assertion: JsObject, values: []JsObject, page: *Page) !void {
+    pub fn _assert(assertion: JsObject, values: []JsObject, page: *Page) !void {
         if (assertion.isTruthy()) {
             return;
         }
@@ -165,165 +164,76 @@ pub const Console = struct {
 };
 
 fn timestamp() u32 {
-    const ts = std.posix.clock_gettime(std.posix.CLOCK.MONOTONIC) catch unreachable;
-    return @intCast(ts.sec);
+    return @import("../../datetime.zig").timestamp();
 }
 
-var test_capture = TestCapture{};
-const testing = @import("../../testing.zig");
-test "Browser.Console" {
-    defer testing.reset();
+// const testing = @import("../../testing.zig");
+// test "Browser.Console" {
+//     defer testing.reset();
 
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
+//     var runner = try testing.jsRunner(testing.tracking_allocator, .{});
+//     defer runner.deinit();
 
-    {
-        try runner.testCases(&.{
-            .{ "console.log('a')", "undefined" },
-            .{ "console.warn('hello world', 23, true, new Object())", "undefined" },
-        }, .{});
+//     {
+//         try runner.testCases(&.{
+//             .{ "console.log('a')", "undefined" },
+//             .{ "console.warn('hello world', 23, true, new Object())", "undefined" },
+//         }, .{});
 
-        const captured = test_capture.captured.items;
-        try testing.expectEqual("[info] args= 1: a", captured[0]);
-        try testing.expectEqual("[warn] args= 1: hello world 2: 23 3: true 4: #<Object>", captured[1]);
-    }
+//         const captured = test_capture.captured.items;
+//         try testing.expectEqual("[info] args= 1: a", captured[0]);
+//         try testing.expectEqual("[warn] args= 1: hello world 2: 23 3: true 4: #<Object>", captured[1]);
+//     }
 
-    {
-        test_capture.reset();
-        try runner.testCases(&.{
-            .{ "console.countReset()", "undefined" },
-            .{ "console.count()", "undefined" },
-            .{ "console.count('teg')", "undefined" },
-            .{ "console.count('teg')", "undefined" },
-            .{ "console.count('teg')", "undefined" },
-            .{ "console.count()", "undefined" },
-            .{ "console.countReset('teg')", "undefined" },
-            .{ "console.countReset()", "undefined" },
-            .{ "console.count()", "undefined" },
-        }, .{});
+//     {
+//         test_capture.reset();
+//         try runner.testCases(&.{
+//             .{ "console.countReset()", "undefined" },
+//             .{ "console.count()", "undefined" },
+//             .{ "console.count('teg')", "undefined" },
+//             .{ "console.count('teg')", "undefined" },
+//             .{ "console.count('teg')", "undefined" },
+//             .{ "console.count()", "undefined" },
+//             .{ "console.countReset('teg')", "undefined" },
+//             .{ "console.countReset()", "undefined" },
+//             .{ "console.count()", "undefined" },
+//         }, .{});
 
-        const captured = test_capture.captured.items;
-        try testing.expectEqual("[invalid counter] label=default", captured[0]);
-        try testing.expectEqual("[count] label=default count=1", captured[1]);
-        try testing.expectEqual("[count] label=teg count=1", captured[2]);
-        try testing.expectEqual("[count] label=teg count=2", captured[3]);
-        try testing.expectEqual("[count] label=teg count=3", captured[4]);
-        try testing.expectEqual("[count] label=default count=2", captured[5]);
-        try testing.expectEqual("[count reset] label=teg count=3", captured[6]);
-        try testing.expectEqual("[count reset] label=default count=2", captured[7]);
-        try testing.expectEqual("[count] label=default count=1", captured[8]);
-    }
+//         const captured = test_capture.captured.items;
+//         try testing.expectEqual("[invalid counter] label=default", captured[0]);
+//         try testing.expectEqual("[count] label=default count=1", captured[1]);
+//         try testing.expectEqual("[count] label=teg count=1", captured[2]);
+//         try testing.expectEqual("[count] label=teg count=2", captured[3]);
+//         try testing.expectEqual("[count] label=teg count=3", captured[4]);
+//         try testing.expectEqual("[count] label=default count=2", captured[5]);
+//         try testing.expectEqual("[count reset] label=teg count=3", captured[6]);
+//         try testing.expectEqual("[count reset] label=default count=2", captured[7]);
+//         try testing.expectEqual("[count] label=default count=1", captured[8]);
+//     }
 
-    {
-        test_capture.reset();
-        try runner.testCases(&.{
-            .{ "console.assert(true)", "undefined" },
-            .{ "console.assert('a', 2, 3, 4)", "undefined" },
-            .{ "console.assert('')", "undefined" },
-            .{ "console.assert('', 'x', true)", "undefined" },
-            .{ "console.assert(false, 'x')", "undefined" },
-        }, .{});
+//     {
+//         test_capture.reset();
+//         try runner.testCases(&.{
+//             .{ "console.assert(true)", "undefined" },
+//             .{ "console.assert('a', 2, 3, 4)", "undefined" },
+//             .{ "console.assert('')", "undefined" },
+//             .{ "console.assert('', 'x', true)", "undefined" },
+//             .{ "console.assert(false, 'x')", "undefined" },
+//         }, .{});
 
-        const captured = test_capture.captured.items;
-        try testing.expectEqual("[assertion failed] values=", captured[0]);
-        try testing.expectEqual("[assertion failed] values= 1: x 2: true", captured[1]);
-        try testing.expectEqual("[assertion failed] values= 1: x", captured[2]);
-    }
+//         const captured = test_capture.captured.items;
+//         try testing.expectEqual("[assertion failed] values=", captured[0]);
+//         try testing.expectEqual("[assertion failed] values= 1: x 2: true", captured[1]);
+//         try testing.expectEqual("[assertion failed] values= 1: x", captured[2]);
+//     }
 
-    {
-        test_capture.reset();
-        try runner.testCases(&.{
-            .{ "[1].forEach(console.log)", null },
-        }, .{});
+//     {
+//         test_capture.reset();
+//         try runner.testCases(&.{
+//             .{ "[1].forEach(console.log)", null },
+//         }, .{});
 
-        const captured = test_capture.captured.items;
-        try testing.expectEqual("[info] args= 1: 1 2: 0 3: [1]", captured[0]);
-    }
-}
-
-const TestCapture = struct {
-    captured: std.ArrayListUnmanaged([]const u8) = .{},
-
-    fn separator(_: *const TestCapture) []const u8 {
-        return " ";
-    }
-
-    fn reset(self: *TestCapture) void {
-        self.captured = .{};
-    }
-
-    fn debug(
-        self: *TestCapture,
-        comptime scope: @Type(.enum_literal),
-        comptime msg: []const u8,
-        args: anytype,
-    ) void {
-        self.capture(scope, msg, args);
-    }
-
-    fn info(
-        self: *TestCapture,
-        comptime scope: @Type(.enum_literal),
-        comptime msg: []const u8,
-        args: anytype,
-    ) void {
-        self.capture(scope, msg, args);
-    }
-
-    fn warn(
-        self: *TestCapture,
-        comptime scope: @Type(.enum_literal),
-        comptime msg: []const u8,
-        args: anytype,
-    ) void {
-        self.capture(scope, msg, args);
-    }
-
-    fn err(
-        self: *TestCapture,
-        comptime scope: @Type(.enum_literal),
-        comptime msg: []const u8,
-        args: anytype,
-    ) void {
-        self.capture(scope, msg, args);
-    }
-
-    fn fatal(
-        self: *TestCapture,
-        comptime scope: @Type(.enum_literal),
-        comptime msg: []const u8,
-        args: anytype,
-    ) void {
-        self.capture(scope, msg, args);
-    }
-
-    fn capture(
-        self: *TestCapture,
-        comptime scope: @Type(.enum_literal),
-        comptime msg: []const u8,
-        args: anytype,
-    ) void {
-        self._capture(scope, msg, args) catch unreachable;
-    }
-
-    fn _capture(
-        self: *TestCapture,
-        comptime scope: @Type(.enum_literal),
-        comptime msg: []const u8,
-        args: anytype,
-    ) !void {
-        std.debug.assert(scope == .console);
-
-        const allocator = testing.arena_allocator;
-        var buf: std.ArrayListUnmanaged(u8) = .empty;
-        try buf.appendSlice(allocator, "[" ++ msg ++ "] ");
-
-        inline for (@typeInfo(@TypeOf(args)).@"struct".fields) |f| {
-            try buf.appendSlice(allocator, f.name);
-            try buf.append(allocator, '=');
-            try @import("../../log.zig").writeValue(.pretty, @field(args, f.name), buf.writer(allocator));
-            try buf.append(allocator, ' ');
-        }
-        self.captured.append(testing.arena_allocator, std.mem.trimRight(u8, buf.items, " ")) catch unreachable;
-    }
-};
+//         const captured = test_capture.captured.items;
+//         try testing.expectEqual("[info] args= 1: 1 2: 0 3: [1]", captured[0]);
+//     }
+// }

src/browser/crypto/crypto.zig

@@ -17,16 +17,21 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const Env = @import("../env.zig").Env;
 const uuidv4 = @import("../../id.zig").uuidv4;
 
 // https://w3c.github.io/webcrypto/#crypto-interface
 pub const Crypto = struct {
-    pub fn _getRandomValues(_: *const Crypto, into: RandomValues) !void {
+    _not_empty: bool = true,
+
+    pub fn _getRandomValues(_: *const Crypto, js_obj: Env.JsObject) !Env.JsObject {
+        var into = try js_obj.toZig(Crypto, "getRandomValues", RandomValues);
         const buf = into.asBuffer();
         if (buf.len > 65_536) {
             return error.QuotaExceededError;
         }
         std.crypto.random.bytes(buf);
+        return js_obj;
     }
 
     pub fn _randomUUID(_: *const Crypto) [36]u8 {
@@ -47,36 +52,20 @@ const RandomValues = union(enum) {
     uint64: []u64,
 
     fn asBuffer(self: RandomValues) []u8 {
-        switch (self) {
-            .int8 => |b| return (@as([]u8, @ptrCast(b)))[0..b.len],
-            .uint8 => |b| return (@as([]u8, @ptrCast(b)))[0..b.len],
-            .int16 => |b| return (@as([]u8, @ptrCast(b)))[0 .. b.len * 2],
-            .uint16 => |b| return (@as([]u8, @ptrCast(b)))[0 .. b.len * 2],
-            .int32 => |b| return (@as([]u8, @ptrCast(b)))[0 .. b.len * 4],
-            .uint32 => |b| return (@as([]u8, @ptrCast(b)))[0 .. b.len * 4],
-            .int64 => |b| return (@as([]u8, @ptrCast(b)))[0 .. b.len * 8],
-            .uint64 => |b| return (@as([]u8, @ptrCast(b)))[0 .. b.len * 8],
-        }
+        return switch (self) {
+            .int8 => |b| (@as([]u8, @ptrCast(b)))[0..b.len],
+            .uint8 => |b| (@as([]u8, @ptrCast(b)))[0..b.len],
+            .int16 => |b| (@as([]u8, @ptrCast(b)))[0 .. b.len * 2],
+            .uint16 => |b| (@as([]u8, @ptrCast(b)))[0 .. b.len * 2],
+            .int32 => |b| (@as([]u8, @ptrCast(b)))[0 .. b.len * 4],
+            .uint32 => |b| (@as([]u8, @ptrCast(b)))[0 .. b.len * 4],
+            .int64 => |b| (@as([]u8, @ptrCast(b)))[0 .. b.len * 8],
+            .uint64 => |b| (@as([]u8, @ptrCast(b)))[0 .. b.len * 8],
+        };
     }
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.Crypto" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "const a = crypto.randomUUID();", "undefined" },
-        .{ "const b = crypto.randomUUID();", "undefined" },
-        .{ "a.length;", "36" },
-        .{ "a.length;", "36" },
-        .{ "a == b;", "false" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "try { crypto.getRandomValues(new BigUint64Array(8193)) } catch(e) { e.message == 'QuotaExceededError' }", "true" },
-        .{ "let r1 = new Int32Array(5)", "undefined" },
-        .{ "crypto.getRandomValues(r1)", "undefined" },
-        .{ "new Set(r1).size", "5" },
-    }, .{});
+test "Browser: Crypto" {
+    try testing.htmlRunner("crypto.html");
 }

src/browser/css/css.zig

@@ -23,6 +23,20 @@ const std = @import("std");
 const Selector = @import("selector.zig").Selector;
 const parser = @import("parser.zig");
 
+pub const Interfaces = .{
+    Css,
+};
+
+// https://developer.mozilla.org/en-US/docs/Web/API/CSS
+pub const Css = struct {
+    _not_empty: bool = true,
+
+    pub fn _supports(_: *Css, _: []const u8, _: ?[]const u8) bool {
+        // TODO: Actually respond with which CSS features we support.
+        return true;
+    }
+};
+
 // parse parse a selector string and returns the parsed result or an error.
 pub fn parse(alloc: std.mem.Allocator, s: []const u8, opts: parser.ParseOptions) parser.ParseError!Selector {
     var p = parser.Parser{ .s = s, .i = 0, .opts = opts };
@@ -31,7 +45,7 @@ pub fn parse(alloc: std.mem.Allocator, s: []const u8, opts: parser.ParseOptions)
 
 // matchFirst call m.match with the first node that matches the selector s, from the
 // descendants of n and returns true. If none matches, it returns false.
-pub fn matchFirst(s: Selector, node: anytype, m: anytype) !bool {
+pub fn matchFirst(s: *const Selector, node: anytype, m: anytype) !bool {
     var c = try node.firstChild();
     while (true) {
         if (c == null) break;
@@ -49,7 +63,7 @@ pub fn matchFirst(s: Selector, node: anytype, m: anytype) !bool {
 
 // matchAll call m.match with the all the nodes that matches the selector s, from the
 // descendants of n.
-pub fn matchAll(s: Selector, node: anytype, m: anytype) !void {
+pub fn matchAll(s: *const Selector, node: anytype, m: anytype) !void {
     var c = try node.firstChild();
     while (true) {
         if (c == null) break;
@@ -174,3 +188,8 @@ test "parse" {
         defer s.deinit(alloc);
     }
 }
+
+const testing = @import("../../testing.zig");
+test "Browser: CSS" {
+    try testing.htmlRunner("css.html");
+}

src/browser/css/libdom_test.zig

@@ -20,18 +20,23 @@ const std = @import("std");
 const css = @import("css.zig");
 const Node = @import("libdom.zig").Node;
 const parser = @import("../netsurf.zig");
+const Allocator = std.mem.Allocator;
 
 const Matcher = struct {
-    const Nodes = std.ArrayList(Node);
+    const Nodes = std.ArrayListUnmanaged(Node);
 
     nodes: Nodes,
+    allocator: Allocator,
 
-    fn init(alloc: std.mem.Allocator) Matcher {
-        return .{ .nodes = Nodes.init(alloc) };
+    fn init(allocator: Allocator) Matcher {
+        return .{
+            .nodes = .empty,
+            .allocator = allocator,
+        };
     }
 
     fn deinit(m: *Matcher) void {
-        m.nodes.deinit();
+        m.nodes.deinit(m.allocator);
     }
 
     fn reset(m: *Matcher) void {
@@ -39,7 +44,7 @@ const Matcher = struct {
     }
 
     pub fn match(m: *Matcher, n: Node) !void {
-        try m.nodes.append(n);
+        try m.nodes.append(m.allocator, n);
     }
 };
 

src/browser/css/match_test.zig

@@ -84,16 +84,20 @@ pub const Node = struct {
 };
 
 const Matcher = struct {
-    const Nodes = std.ArrayList(*const Node);
+    const Nodes = std.ArrayListUnmanaged(*const Node);
 
     nodes: Nodes,
+    allocator: Allocator,
 
-    fn init(alloc: std.mem.Allocator) Matcher {
-        return .{ .nodes = Nodes.init(alloc) };
+    fn init(allocator: Allocator) Matcher {
+        return .{
+            .nodes = .empty,
+            .allocator = allocator,
+        };
     }
 
     fn deinit(m: *Matcher) void {
-        m.nodes.deinit();
+        m.nodes.deinit(self.allocator);
     }
 
     fn reset(m: *Matcher) void {
@@ -101,7 +105,7 @@ const Matcher = struct {
     }
 
     pub fn match(m: *Matcher, n: *const Node) !void {
-        try m.nodes.append(n);
+        try m.nodes.append(self.allocator, n);
     }
 };
 

src/browser/css/parser.zig

@@ -22,6 +22,7 @@
 // see https://github.com/andybalholm/cascadia/blob/master/parser.go
 const std = @import("std");
 const ascii = std.ascii;
+const Allocator = std.mem.Allocator;
 
 const selector = @import("selector.zig");
 const Selector = selector.Selector;
@@ -77,8 +78,8 @@ pub const Parser = struct {
 
     opts: ParseOptions,
 
-    pub fn parse(p: *Parser, alloc: std.mem.Allocator) ParseError!Selector {
-        return p.parseSelectorGroup(alloc);
+    pub fn parse(p: *Parser, allocator: Allocator) ParseError!Selector {
+        return p.parseSelectorGroup(allocator);
     }
 
     // skipWhitespace consumes whitespace characters and comments.
@@ -115,13 +116,13 @@ pub const Parser = struct {
 
     // parseSimpleSelectorSequence parses a selector sequence that applies to
     // a single element.
-    fn parseSimpleSelectorSequence(p: *Parser, alloc: std.mem.Allocator) ParseError!Selector {
+    fn parseSimpleSelectorSequence(p: *Parser, allocator: Allocator) ParseError!Selector {
         if (p.i >= p.s.len) {
             return ParseError.ExpectedSelector;
         }
 
-        var buf = std.ArrayList(Selector).init(alloc);
-        defer buf.deinit();
+        var buf: std.ArrayListUnmanaged(Selector) = .empty;
+        defer buf.deinit(allocator);
 
         switch (p.s[p.i]) {
             '*' => {
@@ -138,20 +139,20 @@ pub const Parser = struct {
                 // There's no type selector. Wait to process the other till the
                 // main loop.
             },
-            else => try buf.append(try p.parseTypeSelector(alloc)),
+            else => try buf.append(allocator, try p.parseTypeSelector(allocator)),
         }
 
         var pseudo_elt: ?PseudoClass = null;
 
         loop: while (p.i < p.s.len) {
             var ns: Selector = switch (p.s[p.i]) {
-                '#' => try p.parseIDSelector(alloc),
-                '.' => try p.parseClassSelector(alloc),
-                '[' => try p.parseAttributeSelector(alloc),
-                ':' => try p.parsePseudoclassSelector(alloc),
+                '#' => try p.parseIDSelector(allocator),
+                '.' => try p.parseClassSelector(allocator),
+                '[' => try p.parseAttributeSelector(allocator),
+                ':' => try p.parsePseudoclassSelector(allocator),
                 else => break :loop,
             };
-            errdefer ns.deinit(alloc);
+            errdefer ns.deinit(allocator);
 
             // From https://drafts.csswg.org/selectors-3/#pseudo-elements :
             // "Only one pseudo-element may appear per selector, and if present
@@ -165,28 +166,32 @@ pub const Parser = struct {
                     if (!p.opts.accept_pseudo_elts) return ParseError.PseudoElementDisabled;
 
                     pseudo_elt = e;
-                    ns.deinit(alloc);
+                    ns.deinit(allocator);
                 },
                 else => {
                     if (pseudo_elt != null) return ParseError.PseudoElementNotAtSelectorEnd;
-                    try buf.append(ns);
+                    try buf.append(allocator, ns);
                 },
             }
         }
 
         // no need wrap the selectors in compoundSelector
-        if (buf.items.len == 1 and pseudo_elt == null) return buf.items[0];
+        if (buf.items.len == 1 and pseudo_elt == null) {
+            return buf.items[0];
+        }
 
-        return .{ .compound = .{ .selectors = try buf.toOwnedSlice(), .pseudo_elt = pseudo_elt } };
+        return .{
+            .compound = .{ .selectors = try buf.toOwnedSlice(allocator), .pseudo_elt = pseudo_elt },
+        };
     }
 
     // parseTypeSelector parses a type selector (one that matches by tag name).
-    fn parseTypeSelector(p: *Parser, alloc: std.mem.Allocator) ParseError!Selector {
-        var buf = std.ArrayList(u8).init(alloc);
-        defer buf.deinit();
-        try p.parseIdentifier(buf.writer());
+    fn parseTypeSelector(p: *Parser, allocator: Allocator) ParseError!Selector {
+        var buf: std.ArrayListUnmanaged(u8) = .empty;
+        defer buf.deinit(allocator);
+        try p.parseIdentifier(buf.writer(allocator));
 
-        return .{ .tag = try buf.toOwnedSlice() };
+        return .{ .tag = try buf.toOwnedSlice(allocator) };
     }
 
     // parseIdentifier parses an identifier.
@@ -204,7 +209,7 @@ pub const Parser = struct {
         }
 
         const c = p.s[p.i];
-        if (!nameStart(c) or c == '\\') {
+        if (!(nameStart(c) or c == '\\')) {
             return ParseError.ExpectedSelector;
         }
 
@@ -314,47 +319,47 @@ pub const Parser = struct {
     }
 
     // parseIDSelector parses a selector that matches by id attribute.
-    fn parseIDSelector(p: *Parser, alloc: std.mem.Allocator) ParseError!Selector {
+    fn parseIDSelector(p: *Parser, allocator: Allocator) ParseError!Selector {
         if (p.i >= p.s.len) return ParseError.ExpectedIDSelector;
         if (p.s[p.i] != '#') return ParseError.ExpectedIDSelector;
 
         p.i += 1;
 
-        var buf = std.ArrayList(u8).init(alloc);
-        defer buf.deinit();
+        var buf: std.ArrayListUnmanaged(u8) = .empty;
+        defer buf.deinit(allocator);
 
-        try p.parseName(buf.writer());
-        return .{ .id = try buf.toOwnedSlice() };
+        try p.parseName(buf.writer(allocator));
+        return .{ .id = try buf.toOwnedSlice(allocator) };
     }
 
     // parseClassSelector parses a selector that matches by class attribute.
-    fn parseClassSelector(p: *Parser, alloc: std.mem.Allocator) ParseError!Selector {
+    fn parseClassSelector(p: *Parser, allocator: Allocator) ParseError!Selector {
         if (p.i >= p.s.len) return ParseError.ExpectedClassSelector;
         if (p.s[p.i] != '.') return ParseError.ExpectedClassSelector;
 
         p.i += 1;
 
-        var buf = std.ArrayList(u8).init(alloc);
-        defer buf.deinit();
+        var buf: std.ArrayListUnmanaged(u8) = .empty;
+        defer buf.deinit(allocator);
 
-        try p.parseIdentifier(buf.writer());
-        return .{ .class = try buf.toOwnedSlice() };
+        try p.parseIdentifier(buf.writer(allocator));
+        return .{ .class = try buf.toOwnedSlice(allocator) };
     }
 
     // parseAttributeSelector parses a selector that matches by attribute value.
-    fn parseAttributeSelector(p: *Parser, alloc: std.mem.Allocator) ParseError!Selector {
+    fn parseAttributeSelector(p: *Parser, allocator: Allocator) ParseError!Selector {
         if (p.i >= p.s.len) return ParseError.ExpectedAttributeSelector;
         if (p.s[p.i] != '[') return ParseError.ExpectedAttributeSelector;
 
         p.i += 1;
         _ = p.skipWhitespace();
 
-        var buf = std.ArrayList(u8).init(alloc);
-        defer buf.deinit();
+        var buf: std.ArrayListUnmanaged(u8) = .empty;
+        defer buf.deinit(allocator);
 
-        try p.parseIdentifier(buf.writer());
-        const key = try buf.toOwnedSlice();
-        errdefer alloc.free(key);
+        try p.parseIdentifier(buf.writer(allocator));
+        const key = try buf.toOwnedSlice(allocator);
+        errdefer allocator.free(key);
 
         lowerstr(key);
 
@@ -377,12 +382,12 @@ pub const Parser = struct {
         var is_val: bool = undefined;
         if (op == .regexp) {
             is_val = false;
-            try p.parseRegex(buf.writer());
+            try p.parseRegex(buf.writer(allocator));
         } else {
             is_val = true;
             switch (p.s[p.i]) {
-                '\'', '"' => try p.parseString(buf.writer()),
-                else => try p.parseIdentifier(buf.writer()),
+                '\'', '"' => try p.parseString(buf.writer(allocator)),
+                else => try p.parseIdentifier(buf.writer(allocator)),
             }
         }
 
@@ -404,8 +409,8 @@ pub const Parser = struct {
 
         return .{ .attribute = .{
             .key = key,
-            .val = if (is_val) try buf.toOwnedSlice() else null,
-            .regexp = if (!is_val) try buf.toOwnedSlice() else null,
+            .val = if (is_val) try buf.toOwnedSlice(allocator) else null,
+            .regexp = if (!is_val) try buf.toOwnedSlice(allocator) else null,
             .op = op,
             .ci = ci,
         } };
@@ -498,7 +503,7 @@ pub const Parser = struct {
     // parsePseudoclassSelector parses a pseudoclass selector like :not(p) or a pseudo-element
     // For backwards compatibility, both ':' and '::' prefix are allowed for pseudo-elements.
     // https://drafts.csswg.org/selectors-3/#pseudo-elements
-    fn parsePseudoclassSelector(p: *Parser, alloc: std.mem.Allocator) ParseError!Selector {
+    fn parsePseudoclassSelector(p: *Parser, allocator: Allocator) ParseError!Selector {
         if (p.i >= p.s.len) return ParseError.ExpectedPseudoClassSelector;
         if (p.s[p.i] != ':') return ParseError.ExpectedPseudoClassSelector;
 
@@ -511,10 +516,10 @@ pub const Parser = struct {
             p.i += 1;
         }
 
-        var buf = std.ArrayList(u8).init(alloc);
-        defer buf.deinit();
+        var buf: std.ArrayListUnmanaged(u8) = .empty;
+        defer buf.deinit(allocator);
 
-        try p.parseIdentifier(buf.writer());
+        try p.parseIdentifier(buf.writer(allocator));
 
         const pseudo_class = try PseudoClass.parse(buf.items);
 
@@ -527,11 +532,11 @@ pub const Parser = struct {
             .not, .has, .haschild => {
                 if (!p.consumeParenthesis()) return ParseError.ExpectedParenthesis;
 
-                const sel = try p.parseSelectorGroup(alloc);
+                const sel = try p.parseSelectorGroup(allocator);
                 if (!p.consumeClosingParenthesis()) return ParseError.ExpectedParenthesisClose;
 
-                const s = try alloc.create(Selector);
-                errdefer alloc.destroy(s);
+                const s = try allocator.create(Selector);
+                errdefer allocator.destroy(s);
                 s.* = sel;
 
                 return .{ .pseudo_class_relative = .{ .pseudo_class = pseudo_class, .match = s } };
@@ -541,16 +546,16 @@ pub const Parser = struct {
                 if (p.i == p.s.len) return ParseError.UnmatchParenthesis;
 
                 switch (p.s[p.i]) {
-                    '\'', '"' => try p.parseString(buf.writer()),
-                    else => try p.parseString(buf.writer()),
+                    '\'', '"' => try p.parseString(buf.writer(allocator)),
+                    else => try p.parseString(buf.writer(allocator)),
                 }
 
                 _ = p.skipWhitespace();
                 if (p.i >= p.s.len) return ParseError.InvalidPseudoClass;
                 if (!p.consumeClosingParenthesis()) return ParseError.ExpectedParenthesisClose;
 
-                const val = try buf.toOwnedSlice();
-                errdefer alloc.free(val);
+                const val = try buf.toOwnedSlice(allocator);
+                errdefer allocator.free(val);
 
                 lowerstr(val);
 
@@ -559,15 +564,15 @@ pub const Parser = struct {
             .matches, .matchesown => {
                 if (!p.consumeParenthesis()) return ParseError.ExpectedParenthesis;
 
-                try p.parseRegex(buf.writer());
+                try p.parseRegex(buf.writer(allocator));
                 if (p.i >= p.s.len) return ParseError.InvalidPseudoClassSelector;
                 if (!p.consumeClosingParenthesis()) return ParseError.ExpectedParenthesisClose;
 
-                return .{ .pseudo_class_regexp = .{ .own = pseudo_class == .matchesown, .regexp = try buf.toOwnedSlice() } };
+                return .{ .pseudo_class_regexp = .{ .own = pseudo_class == .matchesown, .regexp = try buf.toOwnedSlice(allocator) } };
             },
             .nth_child, .nth_last_child, .nth_of_type, .nth_last_of_type => {
                 if (!p.consumeParenthesis()) return ParseError.ExpectedParenthesis;
-                const nth = try p.parseNth(alloc);
+                const nth = try p.parseNth(allocator);
                 if (!p.consumeClosingParenthesis()) return ParseError.ExpectedParenthesisClose;
 
                 const last = pseudo_class == .nth_last_child or pseudo_class == .nth_last_of_type;
@@ -582,18 +587,19 @@ pub const Parser = struct {
             .only_of_type => return .{ .pseudo_class_only_child = true },
             .input, .empty, .root, .link => return .{ .pseudo_class = pseudo_class },
             .enabled, .disabled, .checked => return .{ .pseudo_class = pseudo_class },
+            .visible => return .{ .pseudo_class = pseudo_class },
             .lang => {
                 if (!p.consumeParenthesis()) return ParseError.ExpectedParenthesis;
                 if (p.i == p.s.len) return ParseError.UnmatchParenthesis;
 
-                try p.parseIdentifier(buf.writer());
+                try p.parseIdentifier(buf.writer(allocator));
 
                 _ = p.skipWhitespace();
                 if (p.i >= p.s.len) return ParseError.InvalidPseudoClass;
                 if (!p.consumeClosingParenthesis()) return ParseError.ExpectedParenthesisClose;
 
-                const val = try buf.toOwnedSlice();
-                errdefer alloc.free(val);
+                const val = try buf.toOwnedSlice(allocator);
+                errdefer allocator.free(val);
                 lowerstr(val);
 
                 return .{ .pseudo_class_lang = val };
@@ -605,7 +611,7 @@ pub const Parser = struct {
             .after, .backdrop, .before, .cue, .first_letter => return .{ .pseudo_element = pseudo_class },
             .first_line, .grammar_error, .marker, .placeholder => return .{ .pseudo_element = pseudo_class },
             .selection, .spelling_error => return .{ .pseudo_element = pseudo_class },
-            .modal => return .{ .pseudo_element = pseudo_class },
+            .modal, .popover_open => return .{ .pseudo_element = pseudo_class },
         }
     }
 
@@ -621,30 +627,32 @@ pub const Parser = struct {
     }
 
     // parseSelectorGroup parses a group of selectors, separated by commas.
-    fn parseSelectorGroup(p: *Parser, alloc: std.mem.Allocator) ParseError!Selector {
-        const s = try p.parseSelector(alloc);
+    fn parseSelectorGroup(p: *Parser, allocator: Allocator) ParseError!Selector {
+        const s = try p.parseSelector(allocator);
 
-        var buf = std.ArrayList(Selector).init(alloc);
-        defer buf.deinit();
+        var buf: std.ArrayListUnmanaged(Selector) = .empty;
+        defer buf.deinit(allocator);
 
-        try buf.append(s);
+        try buf.append(allocator, s);
 
         while (p.i < p.s.len) {
             if (p.s[p.i] != ',') break;
             p.i += 1;
-            const ss = try p.parseSelector(alloc);
-            try buf.append(ss);
+            const ss = try p.parseSelector(allocator);
+            try buf.append(allocator, ss);
         }
 
-        if (buf.items.len == 1) return buf.items[0];
+        if (buf.items.len == 1) {
+            return buf.items[0];
+        }
 
-        return .{ .group = try buf.toOwnedSlice() };
+        return .{ .group = try buf.toOwnedSlice(allocator) };
     }
 
     // parseSelector parses a selector that may include combinators.
-    fn parseSelector(p: *Parser, alloc: std.mem.Allocator) ParseError!Selector {
+    fn parseSelector(p: *Parser, allocator: Allocator) ParseError!Selector {
         _ = p.skipWhitespace();
-        var s = try p.parseSimpleSelectorSequence(alloc);
+        var s = try p.parseSimpleSelectorSequence(allocator);
 
         while (true) {
             var combinator: Combinator = .empty;
@@ -672,17 +680,21 @@ pub const Parser = struct {
                 return s;
             }
 
-            const c = try p.parseSimpleSelectorSequence(alloc);
+            const c = try p.parseSimpleSelectorSequence(allocator);
 
-            const first = try alloc.create(Selector);
-            errdefer alloc.destroy(first);
+            const first = try allocator.create(Selector);
+            errdefer allocator.destroy(first);
             first.* = s;
 
-            const second = try alloc.create(Selector);
-            errdefer alloc.destroy(second);
+            const second = try allocator.create(Selector);
+            errdefer allocator.destroy(second);
             second.* = c;
 
-            s = Selector{ .combined = .{ .first = first, .second = second, .combinator = combinator } };
+            s = Selector{ .combined = .{
+                .first = first,
+                .second = second,
+                .combinator = combinator,
+            } };
         }
 
         return s;
@@ -775,7 +787,7 @@ pub const Parser = struct {
     }
 
     // parseNth parses the argument for :nth-child (normally of the form an+b).
-    fn parseNth(p: *Parser, alloc: std.mem.Allocator) ParseError![2]isize {
+    fn parseNth(p: *Parser, allocator: Allocator) ParseError![2]isize {
         // initial state
         if (p.i >= p.s.len) return ParseError.ExpectedNthExpression;
         return switch (p.s[p.i]) {
@@ -793,10 +805,10 @@ pub const Parser = struct {
                 return p.parseNthReadN(1);
             },
             'o', 'O', 'e', 'E' => {
-                var buf = std.ArrayList(u8).init(alloc);
-                defer buf.deinit();
+                var buf: std.ArrayListUnmanaged(u8) = .empty;
+                defer buf.deinit(allocator);
 
-                try p.parseName(buf.writer());
+                try p.parseName(buf.writer(allocator));
 
                 if (std.ascii.eqlIgnoreCase("odd", buf.items)) return .{ 2, 1 };
                 if (std.ascii.eqlIgnoreCase("even", buf.items)) return .{ 2, 0 };
@@ -872,7 +884,7 @@ test "parser.skipWhitespace" {
 }
 
 test "parser.parseIdentifier" {
-    const alloc = std.testing.allocator;
+    const allocator = std.testing.allocator;
 
     const testcases = [_]struct {
         s: []const u8, // given value
@@ -888,14 +900,14 @@ test "parser.parseIdentifier" {
         .{ .s = "a\\\"b", .exp = "a\"b" },
     };
 
-    var buf = std.ArrayList(u8).init(alloc);
-    defer buf.deinit();
+    var buf: std.ArrayListUnmanaged(u8) = .empty;
+    defer buf.deinit(allocator);
 
     for (testcases) |tc| {
         buf.clearRetainingCapacity();
 
         var p = Parser{ .s = tc.s, .opts = .{} };
-        p.parseIdentifier(buf.writer()) catch |e| {
+        p.parseIdentifier(buf.writer(allocator)) catch |e| {
             // if error was expected, continue.
             if (tc.err) continue;
 
@@ -910,7 +922,7 @@ test "parser.parseIdentifier" {
 }
 
 test "parser.parseString" {
-    const alloc = std.testing.allocator;
+    const allocator = std.testing.allocator;
 
     const testcases = [_]struct {
         s: []const u8, // given value
@@ -929,14 +941,14 @@ test "parser.parseString" {
         .{ .s = "\"hello world\"", .exp = "hello world" },
     };
 
-    var buf = std.ArrayList(u8).init(alloc);
-    defer buf.deinit();
+    var buf: std.ArrayListUnmanaged(u8) = .empty;
+    defer buf.deinit(allocator);
 
     for (testcases) |tc| {
         buf.clearRetainingCapacity();
 
         var p = Parser{ .s = tc.s, .opts = .{} };
-        p.parseString(buf.writer()) catch |e| {
+        p.parseString(buf.writer(allocator)) catch |e| {
             // if error was expected, continue.
             if (tc.err) continue;
 
@@ -949,3 +961,36 @@ test "parser.parseString" {
         };
     }
 }
+
+test "parser.parse" {
+    var arena = std.heap.ArenaAllocator.init(std.testing.allocator);
+    defer arena.deinit();
+    const allocator = arena.allocator();
+
+    const testcases = [_]struct {
+        s: []const u8, // given value
+        exp: Selector, // expected value
+        err: bool = false,
+    }{
+        .{ .s = "root", .exp = .{ .tag = "root" } },
+        .{ .s = ".root", .exp = .{ .class = "root" } },
+        .{ .s = ":root", .exp = .{ .pseudo_class = .root } },
+        .{ .s = ".\\:bar", .exp = .{ .class = ":bar" } },
+        .{ .s = ".foo\\:bar", .exp = .{ .class = "foo:bar" } },
+    };
+
+    for (testcases) |tc| {
+        var p = Parser{ .s = tc.s, .opts = .{} };
+        const sel = p.parse(allocator) catch |e| {
+            // if error was expected, continue.
+            if (tc.err) continue;
+
+            std.debug.print("test case {s}\n", .{tc.s});
+            return e;
+        };
+        std.testing.expectEqualDeep(tc.exp, sel) catch |e| {
+            std.debug.print("test case {s} : {}\n", .{ tc.s, sel });
+            return e;
+        };
+    }
+}

src/browser/css/selector.zig

@@ -99,6 +99,8 @@ pub const PseudoClass = enum {
     selection,
     spelling_error,
     modal,
+    popover_open,
+    visible,
 
     pub const Error = error{
         InvalidPseudoClass,
@@ -114,52 +116,108 @@ pub const PseudoClass = enum {
     }
 
     pub fn parse(s: []const u8) Error!PseudoClass {
-        if (std.ascii.eqlIgnoreCase(s, "not")) return .not;
-        if (std.ascii.eqlIgnoreCase(s, "has")) return .has;
-        if (std.ascii.eqlIgnoreCase(s, "haschild")) return .haschild;
-        if (std.ascii.eqlIgnoreCase(s, "contains")) return .contains;
-        if (std.ascii.eqlIgnoreCase(s, "containsown")) return .containsown;
-        if (std.ascii.eqlIgnoreCase(s, "matches")) return .matches;
-        if (std.ascii.eqlIgnoreCase(s, "matchesown")) return .matchesown;
-        if (std.ascii.eqlIgnoreCase(s, "nth-child")) return .nth_child;
-        if (std.ascii.eqlIgnoreCase(s, "nth-last-child")) return .nth_last_child;
-        if (std.ascii.eqlIgnoreCase(s, "nth-of-type")) return .nth_of_type;
-        if (std.ascii.eqlIgnoreCase(s, "nth-last-of-type")) return .nth_last_of_type;
-        if (std.ascii.eqlIgnoreCase(s, "first-child")) return .first_child;
-        if (std.ascii.eqlIgnoreCase(s, "last-child")) return .last_child;
-        if (std.ascii.eqlIgnoreCase(s, "first-of-type")) return .first_of_type;
-        if (std.ascii.eqlIgnoreCase(s, "last-of-type")) return .last_of_type;
-        if (std.ascii.eqlIgnoreCase(s, "only-child")) return .only_child;
-        if (std.ascii.eqlIgnoreCase(s, "only-of-type")) return .only_of_type;
-        if (std.ascii.eqlIgnoreCase(s, "input")) return .input;
-        if (std.ascii.eqlIgnoreCase(s, "empty")) return .empty;
-        if (std.ascii.eqlIgnoreCase(s, "root")) return .root;
-        if (std.ascii.eqlIgnoreCase(s, "link")) return .link;
-        if (std.ascii.eqlIgnoreCase(s, "lang")) return .lang;
-        if (std.ascii.eqlIgnoreCase(s, "enabled")) return .enabled;
-        if (std.ascii.eqlIgnoreCase(s, "disabled")) return .disabled;
-        if (std.ascii.eqlIgnoreCase(s, "checked")) return .checked;
-        if (std.ascii.eqlIgnoreCase(s, "visited")) return .visited;
-        if (std.ascii.eqlIgnoreCase(s, "hover")) return .hover;
-        if (std.ascii.eqlIgnoreCase(s, "active")) return .active;
-        if (std.ascii.eqlIgnoreCase(s, "focus")) return .focus;
-        if (std.ascii.eqlIgnoreCase(s, "target")) return .target;
-        if (std.ascii.eqlIgnoreCase(s, "after")) return .after;
-        if (std.ascii.eqlIgnoreCase(s, "backdrop")) return .backdrop;
-        if (std.ascii.eqlIgnoreCase(s, "before")) return .before;
-        if (std.ascii.eqlIgnoreCase(s, "cue")) return .cue;
-        if (std.ascii.eqlIgnoreCase(s, "first-letter")) return .first_letter;
-        if (std.ascii.eqlIgnoreCase(s, "first-line")) return .first_line;
-        if (std.ascii.eqlIgnoreCase(s, "grammar-error")) return .grammar_error;
-        if (std.ascii.eqlIgnoreCase(s, "marker")) return .marker;
-        if (std.ascii.eqlIgnoreCase(s, "placeholder")) return .placeholder;
-        if (std.ascii.eqlIgnoreCase(s, "selection")) return .selection;
-        if (std.ascii.eqlIgnoreCase(s, "spelling-error")) return .spelling_error;
-        if (std.ascii.eqlIgnoreCase(s, "modal")) return .modal;
+        const longest_selector = "nth-last-of-type";
+        if (s.len > longest_selector.len) {
+            return Error.InvalidPseudoClass;
+        }
+
+        var buf: [longest_selector.len]u8 = undefined;
+        const selector = std.ascii.lowerString(&buf, s);
+
+        switch (selector.len) {
+            3 => switch (@as(u24, @bitCast(selector[0..3].*))) {
+                asUint(u24, "cue") => return .cue,
+                asUint(u24, "has") => return .has,
+                asUint(u24, "not") => return .not,
+                else => {},
+            },
+            4 => switch (@as(u32, @bitCast(selector[0..4].*))) {
+                asUint(u32, "lang") => return .lang,
+                asUint(u32, "link") => return .link,
+                asUint(u32, "root") => return .root,
+                else => {},
+            },
+            5 => switch (@as(u40, @bitCast(selector[0..5].*))) {
+                asUint(u40, "after") => return .after,
+                asUint(u40, "empty") => return .empty,
+                asUint(u40, "focus") => return .focus,
+                asUint(u40, "hover") => return .hover,
+                asUint(u40, "input") => return .input,
+                asUint(u40, "modal") => return .modal,
+                else => {},
+            },
+            6 => switch (@as(u48, @bitCast(selector[0..6].*))) {
+                asUint(u48, "active") => return .active,
+                asUint(u48, "before") => return .before,
+                asUint(u48, "marker") => return .marker,
+                asUint(u48, "target") => return .target,
+                else => {},
+            },
+            7 => switch (@as(u56, @bitCast(selector[0..7].*))) {
+                asUint(u56, "checked") => return .checked,
+                asUint(u56, "enabled") => return .enabled,
+                asUint(u56, "matches") => return .matches,
+                asUint(u56, "visited") => return .visited,
+                asUint(u56, "visible") => return .visible,
+                else => {},
+            },
+            8 => switch (@as(u64, @bitCast(selector[0..8].*))) {
+                asUint(u64, "backdrop") => return .backdrop,
+                asUint(u64, "contains") => return .contains,
+                asUint(u64, "disabled") => return .disabled,
+                asUint(u64, "haschild") => return .haschild,
+                else => {},
+            },
+            9 => switch (@as(u72, @bitCast(selector[0..9].*))) {
+                asUint(u72, "nth-child") => return .nth_child,
+                asUint(u72, "selection") => return .selection,
+                else => {},
+            },
+            10 => switch (@as(u80, @bitCast(selector[0..10].*))) {
+                asUint(u80, "first-line") => return .first_line,
+                asUint(u80, "last-child") => return .last_child,
+                asUint(u80, "matchesown") => return .matchesown,
+                asUint(u80, "only-child") => return .only_child,
+                else => {},
+            },
+            11 => switch (@as(u88, @bitCast(selector[0..11].*))) {
+                asUint(u88, "containsown") => return .containsown,
+                asUint(u88, "first-child") => return .first_child,
+                asUint(u88, "nth-of-type") => return .nth_of_type,
+                asUint(u88, "placeholder") => return .placeholder,
+                else => {},
+            },
+            12 => switch (@as(u96, @bitCast(selector[0..12].*))) {
+                asUint(u96, "first-letter") => return .first_letter,
+                asUint(u96, "last-of-type") => return .last_of_type,
+                asUint(u96, "only-of-type") => return .only_of_type,
+                asUint(u96, "popover-open") => return .popover_open,
+                else => {},
+            },
+            13 => switch (@as(u104, @bitCast(selector[0..13].*))) {
+                asUint(u104, "first-of-type") => return .first_of_type,
+                asUint(u104, "grammar-error") => return .grammar_error,
+                else => {},
+            },
+            14 => switch (@as(u112, @bitCast(selector[0..14].*))) {
+                asUint(u112, "nth-last-child") => return .nth_last_child,
+                asUint(u112, "spelling-error") => return .spelling_error,
+                else => {},
+            },
+            16 => switch (@as(u128, @bitCast(selector[0..16].*))) {
+                asUint(u128, "nth-last-of-type") => return .nth_last_of_type,
+                else => {},
+            },
+            else => {},
+        }
         return Error.InvalidPseudoClass;
     }
 };
 
+fn asUint(comptime T: type, comptime string: []const u8) T {
+    return @bitCast(string[0..string.len].*);
+}
+
 pub const Selector = union(enum) {
     pub const Error = error{
         UnknownCombinedCombinator,
@@ -248,8 +306,8 @@ pub const Selector = union(enum) {
     }
 
     // match returns true if the node matches the selector query.
-    pub fn match(s: Selector, n: anytype) !bool {
-        return switch (s) {
+    pub fn match(s: *const Selector, n: anytype) !bool {
+        return switch (s.*) {
             .tag => |v| n.isElement() and std.ascii.eqlIgnoreCase(v, try n.tag()),
             .id => |v| return n.isElement() and std.mem.eql(u8, v, try n.attr("id") orelse return false),
             .class => |v| return n.isElement() and word(try n.attr("class") orelse return false, v, false),
@@ -511,6 +569,8 @@ pub const Selector = union(enum) {
                     // TODO implement using the url fragment.
                     // see https://developer.mozilla.org/en-US/docs/Web/CSS/:target
                     .target => return false,
+                    // visible always returns true.
+                    .visible => return true,
 
                     // all others pseudo class are handled by specialized
                     // pseudo_class_X selectors.
@@ -734,8 +794,8 @@ pub const Selector = union(enum) {
         return false;
     }
 
-    pub fn deinit(sel: Selector, alloc: std.mem.Allocator) void {
-        switch (sel) {
+    pub fn deinit(sel: *const Selector, alloc: std.mem.Allocator) void {
+        switch (sel.*) {
             .group => |v| {
                 for (v) |vv| vv.deinit(alloc);
                 alloc.free(v);

src/browser/cssom/CSSParser.zig

@@ -0,0 +1,289 @@
+// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+
+const CSSConstants = struct {
+    const IMPORTANT = "!important";
+    const URL_PREFIX = "url(";
+};
+
+const CSSParserState = enum {
+    seek_name,
+    in_name,
+    seek_colon,
+    seek_value,
+    in_value,
+    in_quoted_value,
+    in_single_quoted_value,
+    in_url,
+    in_important,
+};
+
+const CSSDeclaration = struct {
+    name: []const u8,
+    value: []const u8,
+    is_important: bool,
+};
+
+const CSSParser = @This();
+state: CSSParserState,
+name_start: usize,
+name_end: usize,
+value_start: usize,
+position: usize,
+paren_depth: usize,
+escape_next: bool,
+
+pub fn init() CSSParser {
+    return .{
+        .state = .seek_name,
+        .name_start = 0,
+        .name_end = 0,
+        .value_start = 0,
+        .position = 0,
+        .paren_depth = 0,
+        .escape_next = false,
+    };
+}
+
+pub fn parseDeclarations(arena: Allocator, text: []const u8) ![]CSSDeclaration {
+    var parser = init();
+    var declarations: std.ArrayListUnmanaged(CSSDeclaration) = .empty;
+
+    while (parser.position < text.len) {
+        const c = text[parser.position];
+
+        switch (parser.state) {
+            .seek_name => {
+                if (!std.ascii.isWhitespace(c)) {
+                    parser.name_start = parser.position;
+                    parser.state = .in_name;
+                    continue;
+                }
+            },
+            .in_name => {
+                if (c == ':') {
+                    parser.name_end = parser.position;
+                    parser.state = .seek_value;
+                } else if (std.ascii.isWhitespace(c)) {
+                    parser.name_end = parser.position;
+                    parser.state = .seek_colon;
+                }
+            },
+            .seek_colon => {
+                if (c == ':') {
+                    parser.state = .seek_value;
+                } else if (!std.ascii.isWhitespace(c)) {
+                    parser.state = .seek_name;
+                    continue;
+                }
+            },
+            .seek_value => {
+                if (!std.ascii.isWhitespace(c)) {
+                    parser.value_start = parser.position;
+                    if (c == '"') {
+                        parser.state = .in_quoted_value;
+                    } else if (c == '\'') {
+                        parser.state = .in_single_quoted_value;
+                    } else if (c == 'u' and parser.position + CSSConstants.URL_PREFIX.len <= text.len and std.mem.startsWith(u8, text[parser.position..], CSSConstants.URL_PREFIX)) {
+                        parser.state = .in_url;
+                        parser.paren_depth = 1;
+                        parser.position += 3;
+                    } else {
+                        parser.state = .in_value;
+                        continue;
+                    }
+                }
+            },
+            .in_value => {
+                if (parser.escape_next) {
+                    parser.escape_next = false;
+                } else if (c == '\\') {
+                    parser.escape_next = true;
+                } else if (c == '(') {
+                    parser.paren_depth += 1;
+                } else if (c == ')' and parser.paren_depth > 0) {
+                    parser.paren_depth -= 1;
+                } else if (c == ';' and parser.paren_depth == 0) {
+                    try parser.finishDeclaration(arena, &declarations, text);
+                    parser.state = .seek_name;
+                }
+            },
+            .in_quoted_value => {
+                if (parser.escape_next) {
+                    parser.escape_next = false;
+                } else if (c == '\\') {
+                    parser.escape_next = true;
+                } else if (c == '"') {
+                    parser.state = .in_value;
+                }
+            },
+            .in_single_quoted_value => {
+                if (parser.escape_next) {
+                    parser.escape_next = false;
+                } else if (c == '\\') {
+                    parser.escape_next = true;
+                } else if (c == '\'') {
+                    parser.state = .in_value;
+                }
+            },
+            .in_url => {
+                if (parser.escape_next) {
+                    parser.escape_next = false;
+                } else if (c == '\\') {
+                    parser.escape_next = true;
+                } else if (c == '(') {
+                    parser.paren_depth += 1;
+                } else if (c == ')') {
+                    parser.paren_depth -= 1;
+                    if (parser.paren_depth == 0) {
+                        parser.state = .in_value;
+                    }
+                }
+            },
+            .in_important => {},
+        }
+
+        parser.position += 1;
+    }
+
+    try parser.finalize(arena, &declarations, text);
+
+    return declarations.items;
+}
+
+fn finishDeclaration(self: *CSSParser, arena: Allocator, declarations: *std.ArrayListUnmanaged(CSSDeclaration), text: []const u8) !void {
+    const name = std.mem.trim(u8, text[self.name_start..self.name_end], &std.ascii.whitespace);
+    if (name.len == 0) return;
+
+    const raw_value = text[self.value_start..self.position];
+    const value = std.mem.trim(u8, raw_value, &std.ascii.whitespace);
+
+    var final_value = value;
+    var is_important = false;
+
+    if (std.mem.endsWith(u8, value, CSSConstants.IMPORTANT)) {
+        is_important = true;
+        final_value = std.mem.trimRight(u8, value[0 .. value.len - CSSConstants.IMPORTANT.len], &std.ascii.whitespace);
+    }
+
+    try declarations.append(arena, .{
+        .name = name,
+        .value = final_value,
+        .is_important = is_important,
+    });
+}
+
+fn finalize(self: *CSSParser, arena: Allocator, declarations: *std.ArrayListUnmanaged(CSSDeclaration), text: []const u8) !void {
+    if (self.state != .in_value) {
+        return;
+    }
+    return self.finishDeclaration(arena, declarations, text);
+}
+
+const testing = @import("../../testing.zig");
+test "Browser: CSS.Parser - Simple property" {
+    defer testing.reset();
+
+    const text = "color: red;";
+    const allocator = testing.arena_allocator;
+
+    const declarations = try CSSParser.parseDeclarations(allocator, text);
+
+    try testing.expectEqual(1, declarations.len);
+    try testing.expectEqual("color", declarations[0].name);
+    try testing.expectEqual("red", declarations[0].value);
+    try testing.expectEqual(false, declarations[0].is_important);
+}
+
+test "Browser: CSS.Parser - Property with !important" {
+    defer testing.reset();
+    const text = "margin: 10px !important;";
+    const allocator = testing.arena_allocator;
+
+    const declarations = try CSSParser.parseDeclarations(allocator, text);
+
+    try testing.expectEqual(1, declarations.len);
+    try testing.expectEqual("margin", declarations[0].name);
+    try testing.expectEqual("10px", declarations[0].value);
+    try testing.expectEqual(true, declarations[0].is_important);
+}
+
+test "Browser: CSS.Parser - Multiple properties" {
+    defer testing.reset();
+    const text = "color: red; font-size: 12px; margin: 5px !important;";
+    const allocator = testing.arena_allocator;
+
+    const declarations = try CSSParser.parseDeclarations(allocator, text);
+
+    try testing.expect(declarations.len == 3);
+
+    try testing.expectEqual("color", declarations[0].name);
+    try testing.expectEqual("red", declarations[0].value);
+    try testing.expectEqual(false, declarations[0].is_important);
+
+    try testing.expectEqual("font-size", declarations[1].name);
+    try testing.expectEqual("12px", declarations[1].value);
+    try testing.expectEqual(false, declarations[1].is_important);
+
+    try testing.expectEqual("margin", declarations[2].name);
+    try testing.expectEqual("5px", declarations[2].value);
+    try testing.expectEqual(true, declarations[2].is_important);
+}
+
+test "Browser: CSS.Parser - Quoted value with semicolon" {
+    defer testing.reset();
+    const text = "content: \"Hello; world!\";";
+    const allocator = testing.arena_allocator;
+
+    const declarations = try CSSParser.parseDeclarations(allocator, text);
+
+    try testing.expectEqual(1, declarations.len);
+    try testing.expectEqual("content", declarations[0].name);
+    try testing.expectEqual("\"Hello; world!\"", declarations[0].value);
+    try testing.expectEqual(false, declarations[0].is_important);
+}
+
+test "Browser: CSS.Parser - URL value" {
+    defer testing.reset();
+    const text = "background-image: url(\"test.png\");";
+    const allocator = testing.arena_allocator;
+
+    const declarations = try CSSParser.parseDeclarations(allocator, text);
+
+    try testing.expectEqual(1, declarations.len);
+    try testing.expectEqual("background-image", declarations[0].name);
+    try testing.expectEqual("url(\"test.png\")", declarations[0].value);
+    try testing.expectEqual(false, declarations[0].is_important);
+}
+
+test "Browser: CSS.Parser - Whitespace handling" {
+    defer testing.reset();
+    const text = "  color  :  purple  ;  margin  :  10px  ;  ";
+    const allocator = testing.arena_allocator;
+
+    const declarations = try CSSParser.parseDeclarations(allocator, text);
+
+    try testing.expectEqual(2, declarations.len);
+    try testing.expectEqual("color", declarations[0].name);
+    try testing.expectEqual("purple", declarations[0].value);
+    try testing.expectEqual("margin", declarations[1].name);
+    try testing.expectEqual("10px", declarations[1].value);
+}

src/browser/cssom/CSSRule.zig

@@ -18,7 +18,7 @@
 
 const std = @import("std");
 
-const CSSStyleSheet = @import("css_stylesheet.zig").CSSStyleSheet;
+const CSSStyleSheet = @import("CSSStyleSheet.zig");
 
 pub const Interfaces = .{
     CSSRule,
@@ -26,11 +26,10 @@ pub const Interfaces = .{
 };
 
 // https://developer.mozilla.org/en-US/docs/Web/API/CSSRule
-pub const CSSRule = struct {
-    css_text: []const u8,
-    parent_rule: ?*CSSRule = null,
-    parent_stylesheet: ?*CSSStyleSheet = null,
-};
+const CSSRule = @This();
+css_text: []const u8,
+parent_rule: ?*CSSRule = null,
+parent_stylesheet: ?*CSSStyleSheet = null,
 
 pub const CSSImportRule = struct {
     pub const prototype = *CSSRule;

src/browser/cssom/CSSRuleList.zig

@@ -0,0 +1,52 @@
+// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const CSSRule = @import("CSSRule.zig");
+const StyleSheet = @import("StyleSheet.zig").StyleSheet;
+
+const CSSImportRule = CSSRule.CSSImportRule;
+
+const CSSRuleList = @This();
+list: std.ArrayListUnmanaged([]const u8),
+
+pub fn constructor() CSSRuleList {
+    return .{ .list = .empty };
+}
+
+pub fn _item(self: *CSSRuleList, _index: u32) ?CSSRule {
+    const index: usize = @intCast(_index);
+
+    if (index > self.list.items.len) {
+        return null;
+    }
+
+    // todo: for now, just return null.
+    // this depends on properly parsing CSSRule
+    return null;
+}
+
+pub fn get_length(self: *CSSRuleList) u32 {
+    return @intCast(self.list.items.len);
+}
+
+const testing = @import("../../testing.zig");
+test "Browser: CSS.CSSRuleList" {
+    try testing.htmlRunner("cssom/css_rule_list.html");
+}

src/browser/cssom/CSSStyleDeclaration.zig

@@ -0,0 +1,958 @@
+// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const Page = @import("../page.zig").Page;
+const CSSRule = @import("CSSRule.zig");
+const CSSParser = @import("CSSParser.zig");
+
+const Property = struct {
+    value: []const u8,
+    priority: bool,
+};
+
+const CSSStyleDeclaration = @This();
+
+properties: std.StringArrayHashMapUnmanaged(Property),
+
+pub const empty: CSSStyleDeclaration = .{
+    .properties = .empty,
+};
+
+pub fn get_cssFloat(self: *const CSSStyleDeclaration) []const u8 {
+    return self._getPropertyValue("float");
+}
+
+pub fn set_cssFloat(self: *CSSStyleDeclaration, value: ?[]const u8, page: *Page) !void {
+    const final_value = value orelse "";
+    return self._setProperty("float", final_value, null, page);
+}
+
+pub fn get_cssText(self: *const CSSStyleDeclaration, page: *Page) ![]const u8 {
+    var buffer: std.ArrayListUnmanaged(u8) = .empty;
+    const writer = buffer.writer(page.call_arena);
+    var it = self.properties.iterator();
+    while (it.next()) |entry| {
+        const name = entry.key_ptr.*;
+        const property = entry.value_ptr;
+        const escaped = try escapeCSSValue(page.call_arena, property.value);
+        try writer.print("{s}: {s}", .{ name, escaped });
+        if (property.priority) {
+            try writer.writeAll(" !important; ");
+        } else {
+            try writer.writeAll("; ");
+        }
+    }
+    return buffer.items;
+}
+
+// TODO Propagate also upward to parent node
+pub fn set_cssText(self: *CSSStyleDeclaration, text: []const u8, page: *Page) !void {
+    self.properties.clearRetainingCapacity();
+
+    // call_arena is safe here, because _setProperty will dupe the name
+    // using the page's longer-living arena.
+    const declarations = try CSSParser.parseDeclarations(page.call_arena, text);
+
+    for (declarations) |decl| {
+        if (!isValidPropertyName(decl.name)) {
+            continue;
+        }
+        const priority: ?[]const u8 = if (decl.is_important) "important" else null;
+        try self._setProperty(decl.name, decl.value, priority, page);
+    }
+}
+
+pub fn get_length(self: *const CSSStyleDeclaration) usize {
+    return self.properties.count();
+}
+
+pub fn get_parentRule(_: *const CSSStyleDeclaration) ?CSSRule {
+    return null;
+}
+
+pub fn _getPropertyPriority(self: *const CSSStyleDeclaration, name: []const u8) []const u8 {
+    const property = self.properties.getPtr(name) orelse return "";
+    return if (property.priority) "important" else "";
+}
+
+// TODO should handle properly shorthand properties and canonical forms
+pub fn _getPropertyValue(self: *const CSSStyleDeclaration, name: []const u8) []const u8 {
+    if (self.properties.getPtr(name)) |property| {
+        return property.value;
+    }
+
+    // default to everything being visible (unless it's been explicitly set)
+    if (std.mem.eql(u8, name, "visibility")) {
+        return "visible";
+    }
+
+    return "";
+}
+
+pub fn _item(self: *const CSSStyleDeclaration, index: usize) []const u8 {
+    const values = self.properties.entries.items(.key);
+    if (index >= values.len) {
+        return "";
+    }
+    return values[index];
+}
+
+pub fn _removeProperty(self: *CSSStyleDeclaration, name: []const u8) ![]const u8 {
+    const property = self.properties.fetchOrderedRemove(name) orelse return "";
+    return property.value.value;
+}
+
+pub fn _setProperty(self: *CSSStyleDeclaration, name: []const u8, value: []const u8, priority: ?[]const u8, page: *Page) !void {
+    const gop = try self.properties.getOrPut(page.arena, name);
+    if (!gop.found_existing) {
+        const owned_name = try page.arena.dupe(u8, name);
+        gop.key_ptr.* = owned_name;
+    }
+
+    const owned_value = try page.arena.dupe(u8, value);
+    const is_important = priority != null and std.ascii.eqlIgnoreCase(priority.?, "important");
+    gop.value_ptr.* = .{ .value = owned_value, .priority = is_important };
+}
+
+pub fn named_get(self: *const CSSStyleDeclaration, name: []const u8, _: *bool) []const u8 {
+    return self._getPropertyValue(name);
+}
+
+pub fn named_set(self: *CSSStyleDeclaration, name: []const u8, value: []const u8, _: *bool, page: *Page) !void {
+    return self._setProperty(name, value, null, page);
+}
+
+fn isNumericWithUnit(value: []const u8) bool {
+    if (value.len == 0) {
+        return false;
+    }
+
+    const first = value[0];
+
+    if (!std.ascii.isDigit(first) and first != '+' and first != '-' and first != '.') {
+        return false;
+    }
+
+    var i: usize = 0;
+    var has_digit = false;
+    var decimal_point = false;
+
+    while (i < value.len) : (i += 1) {
+        const c = value[i];
+        if (std.ascii.isDigit(c)) {
+            has_digit = true;
+        } else if (c == '.' and !decimal_point) {
+            decimal_point = true;
+        } else if ((c == 'e' or c == 'E') and has_digit) {
+            if (i + 1 >= value.len) return false;
+            if (value[i + 1] != '+' and value[i + 1] != '-' and !std.ascii.isDigit(value[i + 1])) break;
+            i += 1;
+            if (value[i] == '+' or value[i] == '-') {
+                i += 1;
+            }
+            var has_exp_digits = false;
+            while (i < value.len and std.ascii.isDigit(value[i])) : (i += 1) {
+                has_exp_digits = true;
+            }
+            if (!has_exp_digits) return false;
+            break;
+        } else if (c != '-' and c != '+') {
+            break;
+        }
+    }
+
+    if (!has_digit) {
+        return false;
+    }
+
+    if (i == value.len) {
+        return true;
+    }
+
+    const unit = value[i..];
+    return CSSKeywords.isValidUnit(unit);
+}
+
+fn isHexColor(value: []const u8) bool {
+    if (value.len == 0) {
+        return false;
+    }
+    if (value[0] != '#') {
+        return false;
+    }
+
+    const hex_part = value[1..];
+    if (hex_part.len != 3 and hex_part.len != 6 and hex_part.len != 8) {
+        return false;
+    }
+
+    for (hex_part) |c| {
+        if (!std.ascii.isHex(c)) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+fn isMultiValueProperty(value: []const u8) bool {
+    var parts = std.mem.splitAny(u8, value, " ");
+    var multi_value_parts: usize = 0;
+    var all_parts_valid = true;
+
+    while (parts.next()) |part| {
+        if (part.len == 0) continue;
+        multi_value_parts += 1;
+
+        if (isNumericWithUnit(part)) {
+            continue;
+        }
+        if (isHexColor(part)) {
+            continue;
+        }
+        if (CSSKeywords.isKnownKeyword(part)) {
+            continue;
+        }
+        if (CSSKeywords.startsWithFunction(part)) {
+            continue;
+        }
+
+        all_parts_valid = false;
+        break;
+    }
+
+    return multi_value_parts >= 2 and all_parts_valid;
+}
+
+fn isAlreadyQuoted(value: []const u8) bool {
+    return value.len >= 2 and ((value[0] == '"' and value[value.len - 1] == '"') or
+        (value[0] == '\'' and value[value.len - 1] == '\''));
+}
+
+fn isValidPropertyName(name: []const u8) bool {
+    if (name.len == 0) return false;
+
+    if (std.mem.startsWith(u8, name, "--")) {
+        if (name.len == 2) return false;
+        for (name[2..]) |c| {
+            if (!std.ascii.isAlphanumeric(c) and c != '-' and c != '_') {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    const first_char = name[0];
+    if (!std.ascii.isAlphabetic(first_char) and first_char != '-') {
+        return false;
+    }
+
+    if (first_char == '-') {
+        if (name.len < 2) return false;
+
+        if (!std.ascii.isAlphabetic(name[1])) {
+            return false;
+        }
+
+        for (name[2..]) |c| {
+            if (!std.ascii.isAlphanumeric(c) and c != '-') {
+                return false;
+            }
+        }
+    } else {
+        for (name[1..]) |c| {
+            if (!std.ascii.isAlphanumeric(c) and c != '-') {
+                return false;
+            }
+        }
+    }
+
+    return true;
+}
+
+fn extractImportant(value: []const u8) struct { value: []const u8, is_important: bool } {
+    const trimmed = std.mem.trim(u8, value, &std.ascii.whitespace);
+
+    if (std.mem.endsWith(u8, trimmed, "!important")) {
+        const clean_value = std.mem.trimRight(u8, trimmed[0 .. trimmed.len - 10], &std.ascii.whitespace);
+        return .{ .value = clean_value, .is_important = true };
+    }
+
+    return .{ .value = trimmed, .is_important = false };
+}
+
+fn needsQuotes(value: []const u8) bool {
+    if (value.len == 0) return true;
+    if (isAlreadyQuoted(value)) return false;
+
+    if (CSSKeywords.containsSpecialChar(value)) {
+        return true;
+    }
+
+    if (std.mem.indexOfScalar(u8, value, ' ') == null) {
+        return false;
+    }
+
+    const is_url = std.mem.startsWith(u8, value, "url(");
+    const is_function = CSSKeywords.startsWithFunction(value);
+
+    return !isMultiValueProperty(value) and
+        !is_url and
+        !is_function;
+}
+
+fn escapeCSSValue(arena: std.mem.Allocator, value: []const u8) ![]const u8 {
+    if (!needsQuotes(value)) {
+        return value;
+    }
+    var out: std.ArrayListUnmanaged(u8) = .empty;
+
+    // We'll need at least this much space, +2 for the quotes
+    try out.ensureTotalCapacity(arena, value.len + 2);
+    const writer = out.writer(arena);
+
+    try writer.writeByte('"');
+
+    for (value, 0..) |c, i| {
+        switch (c) {
+            '"' => try writer.writeAll("\\\""),
+            '\\' => try writer.writeAll("\\\\"),
+            '\n' => try writer.writeAll("\\A "),
+            '\r' => try writer.writeAll("\\D "),
+            '\t' => try writer.writeAll("\\9 "),
+            0...8, 11, 12, 14...31, 127 => {
+                try writer.print("\\{x}", .{c});
+                if (i + 1 < value.len and std.ascii.isHex(value[i + 1])) {
+                    try writer.writeByte(' ');
+                }
+            },
+            else => try writer.writeByte(c),
+        }
+    }
+
+    try writer.writeByte('"');
+    return out.items;
+}
+
+fn isKnownKeyword(value: []const u8) bool {
+    return CSSKeywords.isKnownKeyword(value);
+}
+
+fn containsSpecialChar(value: []const u8) bool {
+    return CSSKeywords.containsSpecialChar(value);
+}
+
+const CSSKeywords = struct {
+    const BORDER_STYLES = [_][]const u8{
+        "none", "solid", "dotted", "dashed", "double", "groove", "ridge", "inset", "outset",
+    };
+
+    const COLOR_NAMES = [_][]const u8{
+        "black",        "white",   "red", "green", "blue", "yellow", "purple", "gray", "transparent",
+        "currentColor", "inherit",
+    };
+
+    const POSITION_KEYWORDS = [_][]const u8{
+        "auto", "center", "left", "right", "top", "bottom",
+    };
+
+    const BACKGROUND_REPEAT = [_][]const u8{
+        "repeat", "no-repeat", "repeat-x", "repeat-y", "space", "round",
+    };
+
+    const FONT_STYLES = [_][]const u8{
+        "normal", "italic", "oblique", "bold", "bolder", "lighter",
+    };
+
+    const FONT_SIZES = [_][]const u8{
+        "xx-small", "x-small", "small", "medium", "large", "x-large", "xx-large",
+        "smaller",  "larger",
+    };
+
+    const FONT_FAMILIES = [_][]const u8{
+        "serif", "sans-serif", "monospace", "cursive", "fantasy", "system-ui",
+    };
+
+    const CSS_GLOBAL = [_][]const u8{
+        "initial", "inherit", "unset", "revert",
+    };
+
+    const DISPLAY_VALUES = [_][]const u8{
+        "block", "inline", "inline-block", "flex", "grid", "none",
+    };
+
+    const UNITS = [_][]const u8{
+        // LENGTH
+        "px",   "em", "rem", "vw",  "vh",  "vmin", "vmax", "%", "pt", "pc", "in",  "cm",  "mm",
+        "ex",   "ch", "fr",
+
+        // ANGLE
+         "deg", "rad", "grad", "turn",
+
+        // TIME
+        "s", "ms",
+
+        // FREQUENCY
+        "hz", "khz",
+
+        // RESOLUTION
+        "dpi", "dpcm",
+        "dppx",
+    };
+
+    const SPECIAL_CHARS = [_]u8{
+        '"', '\'', ';', '{', '}', '\\', '<', '>', '/', '\n', '\t', '\r', '\x00', '\x7F',
+    };
+
+    const FUNCTIONS = [_][]const u8{
+        "rgb(",             "rgba(",            "hsl(",            "hsla(",      "url(",    "calc(",  "var(",  "attr(",
+        "linear-gradient(", "radial-gradient(", "conic-gradient(", "translate(", "rotate(", "scale(", "skew(", "matrix(",
+    };
+
+    const KEYWORDS = BORDER_STYLES ++ COLOR_NAMES ++ POSITION_KEYWORDS ++
+        BACKGROUND_REPEAT ++ FONT_STYLES ++ FONT_SIZES ++ FONT_FAMILIES ++
+        CSS_GLOBAL ++ DISPLAY_VALUES;
+
+    const MAX_KEYWORD_LEN = lengthOfLongestValue(&KEYWORDS);
+
+    pub fn isKnownKeyword(value: []const u8) bool {
+        if (value.len > MAX_KEYWORD_LEN) {
+            return false;
+        }
+        var buf: [MAX_KEYWORD_LEN]u8 = undefined;
+        const normalized = std.ascii.lowerString(&buf, value);
+
+        for (KEYWORDS) |keyword| {
+            if (std.ascii.eqlIgnoreCase(normalized, keyword)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    pub fn containsSpecialChar(value: []const u8) bool {
+        return std.mem.indexOfAny(u8, value, &SPECIAL_CHARS) != null;
+    }
+
+    const MAX_UNIT_LEN = lengthOfLongestValue(&UNITS);
+
+    pub fn isValidUnit(unit: []const u8) bool {
+        if (unit.len > MAX_UNIT_LEN) {
+            return false;
+        }
+        var buf: [MAX_UNIT_LEN]u8 = undefined;
+        const normalized = std.ascii.lowerString(&buf, unit);
+
+        for (UNITS) |u| {
+            if (std.mem.eql(u8, normalized, u)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    pub fn startsWithFunction(value: []const u8) bool {
+        const pos = std.mem.indexOfScalar(u8, value, '(') orelse return false;
+        if (pos == 0) return false;
+
+        if (std.mem.indexOfScalarPos(u8, value, pos, ')') == null) {
+            return false;
+        }
+        const function_name = value[0..pos];
+        return isValidFunctionName(function_name);
+    }
+
+    fn isValidFunctionName(name: []const u8) bool {
+        if (name.len == 0) return false;
+
+        const first = name[0];
+        if (!std.ascii.isAlphabetic(first) and first != '_' and first != '-') {
+            return false;
+        }
+
+        for (name[1..]) |c| {
+            if (!std.ascii.isAlphanumeric(c) and c != '_' and c != '-') {
+                return false;
+            }
+        }
+
+        return true;
+    }
+};
+
+fn lengthOfLongestValue(values: []const []const u8) usize {
+    var max: usize = 0;
+    for (values) |v| {
+        max = @max(v.len, max);
+    }
+    return max;
+}
+
+const testing = @import("../../testing.zig");
+test "Browser: CSS.StyleDeclaration" {
+    try testing.htmlRunner("cssom/css_style_declaration.html");
+}
+
+test "Browser: CSS.StyleDeclaration: isNumericWithUnit - valid numbers with units" {
+    try testing.expect(isNumericWithUnit("10px"));
+    try testing.expect(isNumericWithUnit("3.14em"));
+    try testing.expect(isNumericWithUnit("-5rem"));
+    try testing.expect(isNumericWithUnit("+12.5%"));
+    try testing.expect(isNumericWithUnit("0vh"));
+    try testing.expect(isNumericWithUnit(".5vw"));
+}
+
+test "Browser: CSS.StyleDeclaration: isNumericWithUnit - scientific notation" {
+    try testing.expect(isNumericWithUnit("1e5px"));
+    try testing.expect(isNumericWithUnit("2.5E-3em"));
+    try testing.expect(isNumericWithUnit("1e+2rem"));
+    try testing.expect(isNumericWithUnit("-3.14e10px"));
+}
+
+test "Browser: CSS.StyleDeclaration: isNumericWithUnit - edge cases and invalid inputs" {
+    try testing.expect(!isNumericWithUnit(""));
+
+    try testing.expect(!isNumericWithUnit("px"));
+    try testing.expect(!isNumericWithUnit("--px"));
+    try testing.expect(!isNumericWithUnit(".px"));
+
+    try testing.expect(!isNumericWithUnit("1e"));
+    try testing.expect(!isNumericWithUnit("1epx"));
+    try testing.expect(!isNumericWithUnit("1e+"));
+    try testing.expect(!isNumericWithUnit("1e+px"));
+
+    try testing.expect(!isNumericWithUnit("1.2.3px"));
+
+    try testing.expect(!isNumericWithUnit("10xyz"));
+    try testing.expect(!isNumericWithUnit("5invalid"));
+
+    try testing.expect(isNumericWithUnit("10"));
+    try testing.expect(isNumericWithUnit("3.14"));
+    try testing.expect(isNumericWithUnit("-5"));
+}
+
+test "Browser: CSS.StyleDeclaration: isHexColor - valid hex colors" {
+    try testing.expect(isHexColor("#000"));
+    try testing.expect(isHexColor("#fff"));
+    try testing.expect(isHexColor("#123456"));
+    try testing.expect(isHexColor("#abcdef"));
+    try testing.expect(isHexColor("#ABCDEF"));
+    try testing.expect(isHexColor("#12345678"));
+}
+
+test "Browser: CSS.StyleDeclaration: isHexColor - invalid hex colors" {
+    try testing.expect(!isHexColor(""));
+    try testing.expect(!isHexColor("#"));
+    try testing.expect(!isHexColor("000"));
+    try testing.expect(!isHexColor("#00"));
+    try testing.expect(!isHexColor("#0000"));
+    try testing.expect(!isHexColor("#00000"));
+    try testing.expect(!isHexColor("#0000000"));
+    try testing.expect(!isHexColor("#000000000"));
+    try testing.expect(!isHexColor("#gggggg"));
+    try testing.expect(!isHexColor("#123xyz"));
+}
+
+test "Browser: CSS.StyleDeclaration: isMultiValueProperty - valid multi-value properties" {
+    try testing.expect(isMultiValueProperty("10px 20px"));
+    try testing.expect(isMultiValueProperty("solid red"));
+    try testing.expect(isMultiValueProperty("#fff black"));
+    try testing.expect(isMultiValueProperty("1em 2em 3em 4em"));
+    try testing.expect(isMultiValueProperty("rgb(255,0,0) solid"));
+}
+
+test "Browser: CSS.StyleDeclaration: isMultiValueProperty - invalid multi-value properties" {
+    try testing.expect(!isMultiValueProperty(""));
+    try testing.expect(!isMultiValueProperty("10px"));
+    try testing.expect(!isMultiValueProperty("invalid unknown"));
+    try testing.expect(!isMultiValueProperty("10px invalid"));
+    try testing.expect(!isMultiValueProperty("   "));
+}
+
+test "Browser: CSS.StyleDeclaration: isAlreadyQuoted - various quoting scenarios" {
+    try testing.expect(isAlreadyQuoted("\"hello\""));
+    try testing.expect(isAlreadyQuoted("'world'"));
+    try testing.expect(isAlreadyQuoted("\"\""));
+    try testing.expect(isAlreadyQuoted("''"));
+
+    try testing.expect(!isAlreadyQuoted(""));
+    try testing.expect(!isAlreadyQuoted("hello"));
+    try testing.expect(!isAlreadyQuoted("\""));
+    try testing.expect(!isAlreadyQuoted("'"));
+    try testing.expect(!isAlreadyQuoted("\"hello'"));
+    try testing.expect(!isAlreadyQuoted("'hello\""));
+    try testing.expect(!isAlreadyQuoted("\"hello"));
+    try testing.expect(!isAlreadyQuoted("hello\""));
+}
+
+test "Browser: CSS.StyleDeclaration: isValidPropertyName - valid property names" {
+    try testing.expect(isValidPropertyName("color"));
+    try testing.expect(isValidPropertyName("background-color"));
+    try testing.expect(isValidPropertyName("-webkit-transform"));
+    try testing.expect(isValidPropertyName("font-size"));
+    try testing.expect(isValidPropertyName("margin-top"));
+    try testing.expect(isValidPropertyName("z-index"));
+    try testing.expect(isValidPropertyName("line-height"));
+}
+
+test "Browser: CSS.StyleDeclaration: isValidPropertyName - invalid property names" {
+    try testing.expect(!isValidPropertyName(""));
+    try testing.expect(!isValidPropertyName("123color"));
+    try testing.expect(!isValidPropertyName("color!"));
+    try testing.expect(!isValidPropertyName("color space"));
+    try testing.expect(!isValidPropertyName("@color"));
+    try testing.expect(!isValidPropertyName("color.test"));
+    try testing.expect(!isValidPropertyName("color_test"));
+}
+
+test "Browser: CSS.StyleDeclaration: extractImportant - with and without !important" {
+    var result = extractImportant("red !important");
+    try testing.expect(result.is_important);
+    try testing.expectEqual("red", result.value);
+
+    result = extractImportant("blue");
+    try testing.expect(!result.is_important);
+    try testing.expectEqual("blue", result.value);
+
+    result = extractImportant("  green  !important  ");
+    try testing.expect(result.is_important);
+    try testing.expectEqual("green", result.value);
+
+    result = extractImportant("!important");
+    try testing.expect(result.is_important);
+    try testing.expectEqual("", result.value);
+
+    result = extractImportant("important");
+    try testing.expect(!result.is_important);
+    try testing.expectEqual("important", result.value);
+}
+
+test "Browser: CSS.StyleDeclaration: needsQuotes - various scenarios" {
+    try testing.expect(needsQuotes(""));
+    try testing.expect(needsQuotes("hello world"));
+    try testing.expect(needsQuotes("test;"));
+    try testing.expect(needsQuotes("a{b}"));
+    try testing.expect(needsQuotes("test\"quote"));
+
+    try testing.expect(!needsQuotes("\"already quoted\""));
+    try testing.expect(!needsQuotes("'already quoted'"));
+    try testing.expect(!needsQuotes("url(image.png)"));
+    try testing.expect(!needsQuotes("rgb(255, 0, 0)"));
+    try testing.expect(!needsQuotes("10px 20px"));
+    try testing.expect(!needsQuotes("simple"));
+}
+
+test "Browser: CSS.StyleDeclaration: escapeCSSValue - escaping various characters" {
+    const allocator = testing.arena_allocator;
+
+    var result = try escapeCSSValue(allocator, "simple");
+    try testing.expectEqual("simple", result);
+
+    result = try escapeCSSValue(allocator, "\"already quoted\"");
+    try testing.expectEqual("\"already quoted\"", result);
+
+    result = try escapeCSSValue(allocator, "test\"quote");
+    try testing.expectEqual("\"test\\\"quote\"", result);
+
+    result = try escapeCSSValue(allocator, "test\nline");
+    try testing.expectEqual("\"test\\A line\"", result);
+
+    result = try escapeCSSValue(allocator, "test\\back");
+    try testing.expectEqual("\"test\\\\back\"", result);
+}
+
+test "Browser: CSS.StyleDeclaration: CSSKeywords.isKnownKeyword - case sensitivity" {
+    try testing.expect(CSSKeywords.isKnownKeyword("red"));
+    try testing.expect(CSSKeywords.isKnownKeyword("solid"));
+    try testing.expect(CSSKeywords.isKnownKeyword("center"));
+    try testing.expect(CSSKeywords.isKnownKeyword("inherit"));
+
+    try testing.expect(CSSKeywords.isKnownKeyword("RED"));
+    try testing.expect(CSSKeywords.isKnownKeyword("Red"));
+    try testing.expect(CSSKeywords.isKnownKeyword("SOLID"));
+    try testing.expect(CSSKeywords.isKnownKeyword("Center"));
+
+    try testing.expect(!CSSKeywords.isKnownKeyword("invalid"));
+    try testing.expect(!CSSKeywords.isKnownKeyword("unknown"));
+    try testing.expect(!CSSKeywords.isKnownKeyword(""));
+}
+
+test "Browser: CSS.StyleDeclaration: CSSKeywords.containsSpecialChar - various special characters" {
+    try testing.expect(CSSKeywords.containsSpecialChar("test\"quote"));
+    try testing.expect(CSSKeywords.containsSpecialChar("test'quote"));
+    try testing.expect(CSSKeywords.containsSpecialChar("test;end"));
+    try testing.expect(CSSKeywords.containsSpecialChar("test{brace"));
+    try testing.expect(CSSKeywords.containsSpecialChar("test}brace"));
+    try testing.expect(CSSKeywords.containsSpecialChar("test\\back"));
+    try testing.expect(CSSKeywords.containsSpecialChar("test<angle"));
+    try testing.expect(CSSKeywords.containsSpecialChar("test>angle"));
+    try testing.expect(CSSKeywords.containsSpecialChar("test/slash"));
+
+    try testing.expect(!CSSKeywords.containsSpecialChar("normal-text"));
+    try testing.expect(!CSSKeywords.containsSpecialChar("text123"));
+    try testing.expect(!CSSKeywords.containsSpecialChar(""));
+}
+
+test "Browser: CSS.StyleDeclaration: CSSKeywords.isValidUnit - various units" {
+    try testing.expect(CSSKeywords.isValidUnit("px"));
+    try testing.expect(CSSKeywords.isValidUnit("em"));
+    try testing.expect(CSSKeywords.isValidUnit("rem"));
+    try testing.expect(CSSKeywords.isValidUnit("%"));
+
+    try testing.expect(CSSKeywords.isValidUnit("deg"));
+    try testing.expect(CSSKeywords.isValidUnit("rad"));
+
+    try testing.expect(CSSKeywords.isValidUnit("s"));
+    try testing.expect(CSSKeywords.isValidUnit("ms"));
+
+    try testing.expect(CSSKeywords.isValidUnit("PX"));
+
+    try testing.expect(!CSSKeywords.isValidUnit("invalid"));
+    try testing.expect(!CSSKeywords.isValidUnit(""));
+}
+
+test "Browser: CSS.StyleDeclaration: CSSKeywords.startsWithFunction - function detection" {
+    try testing.expect(CSSKeywords.startsWithFunction("rgb(255, 0, 0)"));
+    try testing.expect(CSSKeywords.startsWithFunction("rgba(255, 0, 0, 0.5)"));
+    try testing.expect(CSSKeywords.startsWithFunction("url(image.png)"));
+    try testing.expect(CSSKeywords.startsWithFunction("calc(100% - 20px)"));
+    try testing.expect(CSSKeywords.startsWithFunction("var(--custom-property)"));
+    try testing.expect(CSSKeywords.startsWithFunction("linear-gradient(to right, red, blue)"));
+
+    try testing.expect(CSSKeywords.startsWithFunction("custom-function(args)"));
+    try testing.expect(CSSKeywords.startsWithFunction("unknown(test)"));
+
+    try testing.expect(!CSSKeywords.startsWithFunction("not-a-function"));
+    try testing.expect(!CSSKeywords.startsWithFunction("missing-paren)"));
+    try testing.expect(!CSSKeywords.startsWithFunction("missing-close("));
+    try testing.expect(!CSSKeywords.startsWithFunction(""));
+    try testing.expect(!CSSKeywords.startsWithFunction("rgb"));
+}
+
+test "Browser: CSS.StyleDeclaration: isNumericWithUnit - whitespace handling" {
+    try testing.expect(!isNumericWithUnit(" 10px"));
+    try testing.expect(!isNumericWithUnit("10 px"));
+    try testing.expect(!isNumericWithUnit("10px "));
+    try testing.expect(!isNumericWithUnit(" 10 px "));
+}
+
+test "Browser: CSS.StyleDeclaration: extractImportant - whitespace edge cases" {
+    var result = extractImportant("   ");
+    try testing.expect(!result.is_important);
+    try testing.expectEqual("", result.value);
+
+    result = extractImportant("\t\n\r !important\t\n");
+    try testing.expect(result.is_important);
+    try testing.expectEqual("", result.value);
+
+    result = extractImportant("red\t!important");
+    try testing.expect(result.is_important);
+    try testing.expectEqual("red", result.value);
+}
+
+test "Browser: CSS.StyleDeclaration: isHexColor - mixed case handling" {
+    try testing.expect(isHexColor("#AbC"));
+    try testing.expect(isHexColor("#123aBc"));
+    try testing.expect(isHexColor("#FFffFF"));
+    try testing.expect(isHexColor("#000FFF"));
+}
+
+test "Browser: CSS.StyleDeclaration: edge case - very long inputs" {
+    const long_valid = "a" ** 1000 ++ "px";
+    try testing.expect(!isNumericWithUnit(long_valid)); // not numeric
+
+    const long_property = "a-" ** 100 ++ "property";
+    try testing.expect(isValidPropertyName(long_property));
+
+    const long_hex = "#" ++ "a" ** 20;
+    try testing.expect(!isHexColor(long_hex));
+}
+
+test "Browser: CSS.StyleDeclaration: boundary conditions - numeric parsing" {
+    try testing.expect(isNumericWithUnit("0px"));
+    try testing.expect(isNumericWithUnit("0.0px"));
+    try testing.expect(isNumericWithUnit(".0px"));
+    try testing.expect(isNumericWithUnit("0.px"));
+
+    try testing.expect(isNumericWithUnit("999999999px"));
+    try testing.expect(isNumericWithUnit("1.7976931348623157e+308px"));
+
+    try testing.expect(isNumericWithUnit("0.000000001px"));
+    try testing.expect(isNumericWithUnit("1e-100px"));
+}
+
+test "Browser: CSS.StyleDeclaration: extractImportant - malformed important declarations" {
+    var result = extractImportant("red ! important");
+    try testing.expect(!result.is_important);
+    try testing.expectEqual("red ! important", result.value);
+
+    result = extractImportant("red !Important");
+    try testing.expect(!result.is_important);
+    try testing.expectEqual("red !Important", result.value);
+
+    result = extractImportant("red !IMPORTANT");
+    try testing.expect(!result.is_important);
+    try testing.expectEqual("red !IMPORTANT", result.value);
+
+    result = extractImportant("!importantred");
+    try testing.expect(!result.is_important);
+    try testing.expectEqual("!importantred", result.value);
+
+    result = extractImportant("red !important !important");
+    try testing.expect(result.is_important);
+    try testing.expectEqual("red !important", result.value);
+}
+
+test "Browser: CSS.StyleDeclaration: isMultiValueProperty - complex spacing scenarios" {
+    try testing.expect(isMultiValueProperty("10px    20px"));
+    try testing.expect(isMultiValueProperty("solid     red"));
+
+    try testing.expect(isMultiValueProperty("  10px 20px  "));
+
+    try testing.expect(!isMultiValueProperty("10px\t20px"));
+    try testing.expect(!isMultiValueProperty("10px\n20px"));
+
+    try testing.expect(isMultiValueProperty("10px   20px   30px"));
+}
+
+test "Browser: CSS.StyleDeclaration: isAlreadyQuoted - edge cases with quotes" {
+    try testing.expect(isAlreadyQuoted("\"'hello'\""));
+    try testing.expect(isAlreadyQuoted("'\"hello\"'"));
+
+    try testing.expect(isAlreadyQuoted("\"hello\\\"world\""));
+    try testing.expect(isAlreadyQuoted("'hello\\'world'"));
+
+    try testing.expect(!isAlreadyQuoted("\"hello"));
+    try testing.expect(!isAlreadyQuoted("hello\""));
+    try testing.expect(!isAlreadyQuoted("'hello"));
+    try testing.expect(!isAlreadyQuoted("hello'"));
+
+    try testing.expect(isAlreadyQuoted("\"a\""));
+    try testing.expect(isAlreadyQuoted("'b'"));
+}
+
+test "Browser: CSS.StyleDeclaration: needsQuotes - function and URL edge cases" {
+    try testing.expect(!needsQuotes("rgb(255, 0, 0)"));
+    try testing.expect(!needsQuotes("calc(100% - 20px)"));
+
+    try testing.expect(!needsQuotes("url(path with spaces.jpg)"));
+
+    try testing.expect(!needsQuotes("linear-gradient(to right, red, blue)"));
+
+    try testing.expect(needsQuotes("rgb(255, 0, 0"));
+}
+
+test "Browser: CSS.StyleDeclaration: escapeCSSValue - control characters and Unicode" {
+    const allocator = testing.arena_allocator;
+
+    var result = try escapeCSSValue(allocator, "test\ttab");
+    try testing.expectEqual("\"test\\9 tab\"", result);
+
+    result = try escapeCSSValue(allocator, "test\rreturn");
+    try testing.expectEqual("\"test\\D return\"", result);
+
+    result = try escapeCSSValue(allocator, "test\x00null");
+    try testing.expectEqual("\"test\\0null\"", result);
+
+    result = try escapeCSSValue(allocator, "test\x7Fdel");
+    try testing.expectEqual("\"test\\7f del\"", result);
+
+    result = try escapeCSSValue(allocator, "test\"quote\nline\\back");
+    try testing.expectEqual("\"test\\\"quote\\A line\\\\back\"", result);
+}
+
+test "Browser: CSS.StyleDeclaration: isValidPropertyName - CSS custom properties and vendor prefixes" {
+    try testing.expect(isValidPropertyName("--custom-color"));
+    try testing.expect(isValidPropertyName("--my-variable"));
+    try testing.expect(isValidPropertyName("--123"));
+
+    try testing.expect(isValidPropertyName("-webkit-transform"));
+    try testing.expect(isValidPropertyName("-moz-border-radius"));
+    try testing.expect(isValidPropertyName("-ms-filter"));
+    try testing.expect(isValidPropertyName("-o-transition"));
+
+    try testing.expect(!isValidPropertyName("-123invalid"));
+    try testing.expect(!isValidPropertyName("--"));
+    try testing.expect(!isValidPropertyName("-"));
+}
+
+test "Browser: CSS.StyleDeclaration: startsWithFunction - case sensitivity and partial matches" {
+    try testing.expect(CSSKeywords.startsWithFunction("RGB(255, 0, 0)"));
+    try testing.expect(CSSKeywords.startsWithFunction("Rgb(255, 0, 0)"));
+    try testing.expect(CSSKeywords.startsWithFunction("URL(image.png)"));
+
+    try testing.expect(CSSKeywords.startsWithFunction("rg(something)"));
+    try testing.expect(CSSKeywords.startsWithFunction("ur(something)"));
+
+    try testing.expect(CSSKeywords.startsWithFunction("rgb(1,2,3)"));
+    try testing.expect(CSSKeywords.startsWithFunction("rgba(1,2,3,4)"));
+
+    try testing.expect(CSSKeywords.startsWithFunction("my-custom-function(args)"));
+    try testing.expect(CSSKeywords.startsWithFunction("function-with-dashes(test)"));
+
+    try testing.expect(!CSSKeywords.startsWithFunction("123function(test)"));
+}
+
+test "Browser: CSS.StyleDeclaration: isHexColor - Unicode and invalid characters" {
+    try testing.expect(!isHexColor("#ghijkl"));
+    try testing.expect(!isHexColor("#12345g"));
+    try testing.expect(!isHexColor("#xyz"));
+
+    try testing.expect(!isHexColor("#АВС"));
+
+    try testing.expect(!isHexColor("#1234567g"));
+    try testing.expect(!isHexColor("#g2345678"));
+}
+
+test "Browser: CSS.StyleDeclaration: complex integration scenarios" {
+    const allocator = testing.arena_allocator;
+
+    try testing.expect(isMultiValueProperty("rgb(255,0,0) url(bg.jpg)"));
+
+    try testing.expect(!needsQuotes("calc(100% - 20px)"));
+
+    const result = try escapeCSSValue(allocator, "fake(function with spaces");
+    try testing.expectEqual("\"fake(function with spaces\"", result);
+
+    const important_result = extractImportant("rgb(255,0,0) !important");
+    try testing.expect(important_result.is_important);
+    try testing.expectEqual("rgb(255,0,0)", important_result.value);
+}
+
+test "Browser: CSS.StyleDeclaration: performance edge cases - empty and minimal inputs" {
+    try testing.expect(!isNumericWithUnit(""));
+    try testing.expect(!isHexColor(""));
+    try testing.expect(!isMultiValueProperty(""));
+    try testing.expect(!isAlreadyQuoted(""));
+    try testing.expect(!isValidPropertyName(""));
+    try testing.expect(needsQuotes(""));
+    try testing.expect(!CSSKeywords.isKnownKeyword(""));
+    try testing.expect(!CSSKeywords.containsSpecialChar(""));
+    try testing.expect(!CSSKeywords.isValidUnit(""));
+    try testing.expect(!CSSKeywords.startsWithFunction(""));
+
+    try testing.expect(!isNumericWithUnit("a"));
+    try testing.expect(!isHexColor("a"));
+    try testing.expect(!isMultiValueProperty("a"));
+    try testing.expect(!isAlreadyQuoted("a"));
+    try testing.expect(isValidPropertyName("a"));
+    try testing.expect(!needsQuotes("a"));
+}

src/browser/cssom/CSSStyleSheet.zig

@@ -0,0 +1,97 @@
+// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const Env = @import("../env.zig").Env;
+const Page = @import("../page.zig").Page;
+const StyleSheet = @import("StyleSheet.zig");
+const CSSRuleList = @import("CSSRuleList.zig");
+const CSSImportRule = @import("CSSRule.zig").CSSImportRule;
+
+const CSSStyleSheet = @This();
+pub const prototype = *StyleSheet;
+
+proto: StyleSheet,
+css_rules: CSSRuleList,
+owner_rule: ?*CSSImportRule,
+
+const CSSStyleSheetOpts = struct {
+    base_url: ?[]const u8 = null,
+    // TODO: Suupport media
+    disabled: bool = false,
+};
+
+pub fn constructor(_opts: ?CSSStyleSheetOpts) !CSSStyleSheet {
+    const opts = _opts orelse CSSStyleSheetOpts{};
+    return .{
+        .proto = .{ .disabled = opts.disabled },
+        .css_rules = .constructor(),
+        .owner_rule = null,
+    };
+}
+
+pub fn get_ownerRule(_: *CSSStyleSheet) ?*CSSImportRule {
+    return null;
+}
+
+pub fn get_cssRules(self: *CSSStyleSheet) *CSSRuleList {
+    return &self.css_rules;
+}
+
+pub fn _insertRule(self: *CSSStyleSheet, rule: []const u8, _index: ?usize, page: *Page) !usize {
+    const index = _index orelse 0;
+    if (index > self.css_rules.list.items.len) {
+        return error.IndexSize;
+    }
+
+    const arena = page.arena;
+    try self.css_rules.list.insert(arena, index, try arena.dupe(u8, rule));
+    return index;
+}
+
+pub fn _deleteRule(self: *CSSStyleSheet, index: usize) !void {
+    if (index > self.css_rules.list.items.len) {
+        return error.IndexSize;
+    }
+
+    _ = self.css_rules.list.orderedRemove(index);
+}
+
+pub fn _replace(self: *CSSStyleSheet, text: []const u8, page: *Page) !Env.Promise {
+    _ = self;
+    _ = text;
+    // TODO: clear self.css_rules
+    // parse text and re-populate self.css_rules
+
+    const resolver = page.main_context.createPromiseResolver();
+    try resolver.resolve({});
+    return resolver.promise();
+}
+
+pub fn _replaceSync(self: *CSSStyleSheet, text: []const u8) !void {
+    _ = self;
+    _ = text;
+    // TODO: clear self.css_rules
+    // parse text and re-populate self.css_rules
+}
+
+const testing = @import("../../testing.zig");
+test "Browser: CSS.StyleSheet" {
+    try testing.htmlRunner("cssom/css_stylesheet.html");
+}

src/browser/cssom/StyleSheet.zig

@@ -19,37 +19,37 @@
 const parser = @import("../netsurf.zig");
 
 // https://developer.mozilla.org/en-US/docs/Web/API/StyleSheet#specifications
-pub const StyleSheet = struct {
-    disabled: bool = false,
-    href: []const u8 = "",
-    owner_node: ?*parser.Node = null,
-    parent_stylesheet: ?*StyleSheet = null,
-    title: []const u8 = "",
-    type: []const u8 = "text/css",
+const StyleSheet = @This();
 
-    pub fn get_disabled(self: *const StyleSheet) bool {
-        return self.disabled;
-    }
+disabled: bool = false,
+href: []const u8 = "",
+owner_node: ?*parser.Node = null,
+parent_stylesheet: ?*StyleSheet = null,
+title: []const u8 = "",
+type: []const u8 = "text/css",
 
-    pub fn get_href(self: *const StyleSheet) []const u8 {
-        return self.href;
-    }
+pub fn get_disabled(self: *const StyleSheet) bool {
+    return self.disabled;
+}
 
-    // TODO: media
+pub fn get_href(self: *const StyleSheet) []const u8 {
+    return self.href;
+}
 
-    pub fn get_ownerNode(self: *const StyleSheet) ?*parser.Node {
-        return self.owner_node;
-    }
+// TODO: media
 
-    pub fn get_parentStyleSheet(self: *const StyleSheet) ?*StyleSheet {
-        return self.parent_stylesheet;
-    }
+pub fn get_ownerNode(self: *const StyleSheet) ?*parser.Node {
+    return self.owner_node;
+}
 
-    pub fn get_title(self: *const StyleSheet) []const u8 {
-        return self.title;
-    }
+pub fn get_parentStyleSheet(self: *const StyleSheet) ?*StyleSheet {
+    return self.parent_stylesheet;
+}
 
-    pub fn get_type(self: *const StyleSheet) []const u8 {
-        return self.type;
-    }
-};
+pub fn get_title(self: *const StyleSheet) []const u8 {
+    return self.title;
+}
+
+pub fn get_type(self: *const StyleSheet) []const u8 {
+    return self.type;
+}

src/browser/cssom/css_parser.zig

@@ -1,291 +0,0 @@
-// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
-//
-// Francis Bouvier <francis@lightpanda.io>
-// Pierre Tachoire <pierre@lightpanda.io>
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Affero General Public License as
-// published by the Free Software Foundation, either version 3 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Affero General Public License for more details.
-//
-// You should have received a copy of the GNU Affero General Public License
-// along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-const std = @import("std");
-const Allocator = std.mem.Allocator;
-
-const CSSConstants = struct {
-    const IMPORTANT = "!important";
-    const URL_PREFIX = "url(";
-};
-
-pub const CSSParserState = enum {
-    seek_name,
-    in_name,
-    seek_colon,
-    seek_value,
-    in_value,
-    in_quoted_value,
-    in_single_quoted_value,
-    in_url,
-    in_important,
-};
-
-pub const CSSDeclaration = struct {
-    name: []const u8,
-    value: []const u8,
-    is_important: bool,
-};
-
-pub const CSSParser = struct {
-    state: CSSParserState,
-    name_start: usize,
-    name_end: usize,
-    value_start: usize,
-    position: usize,
-    paren_depth: usize,
-    escape_next: bool,
-
-    pub fn init() CSSParser {
-        return .{
-            .state = .seek_name,
-            .name_start = 0,
-            .name_end = 0,
-            .value_start = 0,
-            .position = 0,
-            .paren_depth = 0,
-            .escape_next = false,
-        };
-    }
-
-    pub fn parseDeclarations(arena: Allocator, text: []const u8) ![]CSSDeclaration {
-        var parser = init();
-        var declarations: std.ArrayListUnmanaged(CSSDeclaration) = .empty;
-
-        while (parser.position < text.len) {
-            const c = text[parser.position];
-
-            switch (parser.state) {
-                .seek_name => {
-                    if (!std.ascii.isWhitespace(c)) {
-                        parser.name_start = parser.position;
-                        parser.state = .in_name;
-                        continue;
-                    }
-                },
-                .in_name => {
-                    if (c == ':') {
-                        parser.name_end = parser.position;
-                        parser.state = .seek_value;
-                    } else if (std.ascii.isWhitespace(c)) {
-                        parser.name_end = parser.position;
-                        parser.state = .seek_colon;
-                    }
-                },
-                .seek_colon => {
-                    if (c == ':') {
-                        parser.state = .seek_value;
-                    } else if (!std.ascii.isWhitespace(c)) {
-                        parser.state = .seek_name;
-                        continue;
-                    }
-                },
-                .seek_value => {
-                    if (!std.ascii.isWhitespace(c)) {
-                        parser.value_start = parser.position;
-                        if (c == '"') {
-                            parser.state = .in_quoted_value;
-                        } else if (c == '\'') {
-                            parser.state = .in_single_quoted_value;
-                        } else if (c == 'u' and parser.position + CSSConstants.URL_PREFIX.len <= text.len and std.mem.startsWith(u8, text[parser.position..], CSSConstants.URL_PREFIX)) {
-                            parser.state = .in_url;
-                            parser.paren_depth = 1;
-                            parser.position += 3;
-                        } else {
-                            parser.state = .in_value;
-                            continue;
-                        }
-                    }
-                },
-                .in_value => {
-                    if (parser.escape_next) {
-                        parser.escape_next = false;
-                    } else if (c == '\\') {
-                        parser.escape_next = true;
-                    } else if (c == '(') {
-                        parser.paren_depth += 1;
-                    } else if (c == ')' and parser.paren_depth > 0) {
-                        parser.paren_depth -= 1;
-                    } else if (c == ';' and parser.paren_depth == 0) {
-                        try parser.finishDeclaration(arena, &declarations, text);
-                        parser.state = .seek_name;
-                    }
-                },
-                .in_quoted_value => {
-                    if (parser.escape_next) {
-                        parser.escape_next = false;
-                    } else if (c == '\\') {
-                        parser.escape_next = true;
-                    } else if (c == '"') {
-                        parser.state = .in_value;
-                    }
-                },
-                .in_single_quoted_value => {
-                    if (parser.escape_next) {
-                        parser.escape_next = false;
-                    } else if (c == '\\') {
-                        parser.escape_next = true;
-                    } else if (c == '\'') {
-                        parser.state = .in_value;
-                    }
-                },
-                .in_url => {
-                    if (parser.escape_next) {
-                        parser.escape_next = false;
-                    } else if (c == '\\') {
-                        parser.escape_next = true;
-                    } else if (c == '(') {
-                        parser.paren_depth += 1;
-                    } else if (c == ')') {
-                        parser.paren_depth -= 1;
-                        if (parser.paren_depth == 0) {
-                            parser.state = .in_value;
-                        }
-                    }
-                },
-                .in_important => {},
-            }
-
-            parser.position += 1;
-        }
-
-        try parser.finalize(arena, &declarations, text);
-
-        return declarations.items;
-    }
-
-    fn finishDeclaration(self: *CSSParser, arena: Allocator, declarations: *std.ArrayListUnmanaged(CSSDeclaration), text: []const u8) !void {
-        const name = std.mem.trim(u8, text[self.name_start..self.name_end], &std.ascii.whitespace);
-        if (name.len == 0) return;
-
-        const raw_value = text[self.value_start..self.position];
-        const value = std.mem.trim(u8, raw_value, &std.ascii.whitespace);
-
-        var final_value = value;
-        var is_important = false;
-
-        if (std.mem.endsWith(u8, value, CSSConstants.IMPORTANT)) {
-            is_important = true;
-            final_value = std.mem.trimRight(u8, value[0 .. value.len - CSSConstants.IMPORTANT.len], &std.ascii.whitespace);
-        }
-
-        try declarations.append(arena, .{
-            .name = name,
-            .value = final_value,
-            .is_important = is_important,
-        });
-    }
-
-    fn finalize(self: *CSSParser, arena: Allocator, declarations: *std.ArrayListUnmanaged(CSSDeclaration), text: []const u8) !void {
-        if (self.state != .in_value) {
-            return;
-        }
-        return self.finishDeclaration(arena, declarations, text);
-    }
-};
-
-const testing = @import("../../testing.zig");
-
-test "CSSParser - Simple property" {
-    defer testing.reset();
-
-    const text = "color: red;";
-    const allocator = testing.arena_allocator;
-
-    const declarations = try CSSParser.parseDeclarations(allocator, text);
-
-    try testing.expectEqual(1, declarations.len);
-    try testing.expectEqual("color", declarations[0].name);
-    try testing.expectEqual("red", declarations[0].value);
-    try testing.expectEqual(false, declarations[0].is_important);
-}
-
-test "CSSParser - Property with !important" {
-    defer testing.reset();
-    const text = "margin: 10px !important;";
-    const allocator = testing.arena_allocator;
-
-    const declarations = try CSSParser.parseDeclarations(allocator, text);
-
-    try testing.expectEqual(1, declarations.len);
-    try testing.expectEqual("margin", declarations[0].name);
-    try testing.expectEqual("10px", declarations[0].value);
-    try testing.expectEqual(true, declarations[0].is_important);
-}
-
-test "CSSParser - Multiple properties" {
-    defer testing.reset();
-    const text = "color: red; font-size: 12px; margin: 5px !important;";
-    const allocator = testing.arena_allocator;
-
-    const declarations = try CSSParser.parseDeclarations(allocator, text);
-
-    try testing.expect(declarations.len == 3);
-
-    try testing.expectEqual("color", declarations[0].name);
-    try testing.expectEqual("red", declarations[0].value);
-    try testing.expectEqual(false, declarations[0].is_important);
-
-    try testing.expectEqual("font-size", declarations[1].name);
-    try testing.expectEqual("12px", declarations[1].value);
-    try testing.expectEqual(false, declarations[1].is_important);
-
-    try testing.expectEqual("margin", declarations[2].name);
-    try testing.expectEqual("5px", declarations[2].value);
-    try testing.expectEqual(true, declarations[2].is_important);
-}
-
-test "CSSParser - Quoted value with semicolon" {
-    defer testing.reset();
-    const text = "content: \"Hello; world!\";";
-    const allocator = testing.arena_allocator;
-
-    const declarations = try CSSParser.parseDeclarations(allocator, text);
-
-    try testing.expectEqual(1, declarations.len);
-    try testing.expectEqual("content", declarations[0].name);
-    try testing.expectEqual("\"Hello; world!\"", declarations[0].value);
-    try testing.expectEqual(false, declarations[0].is_important);
-}
-
-test "CSSParser - URL value" {
-    defer testing.reset();
-    const text = "background-image: url(\"test.png\");";
-    const allocator = testing.arena_allocator;
-
-    const declarations = try CSSParser.parseDeclarations(allocator, text);
-
-    try testing.expectEqual(1, declarations.len);
-    try testing.expectEqual("background-image", declarations[0].name);
-    try testing.expectEqual("url(\"test.png\")", declarations[0].value);
-    try testing.expectEqual(false, declarations[0].is_important);
-}
-
-test "CSSParser - Whitespace handling" {
-    defer testing.reset();
-    const text = "  color  :  purple  ;  margin  :  10px  ;  ";
-    const allocator = testing.arena_allocator;
-
-    const declarations = try CSSParser.parseDeclarations(allocator, text);
-
-    try testing.expectEqual(2, declarations.len);
-    try testing.expectEqual("color", declarations[0].name);
-    try testing.expectEqual("purple", declarations[0].value);
-    try testing.expectEqual("margin", declarations[1].name);
-    try testing.expectEqual("10px", declarations[1].value);
-}

src/browser/cssom/css_rule_list.zig

@@ -1,60 +0,0 @@
-// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
-//
-// Francis Bouvier <francis@lightpanda.io>
-// Pierre Tachoire <pierre@lightpanda.io>
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Affero General Public License as
-// published by the Free Software Foundation, either version 3 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Affero General Public License for more details.
-//
-// You should have received a copy of the GNU Affero General Public License
-// along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-const std = @import("std");
-
-const StyleSheet = @import("stylesheet.zig").StyleSheet;
-const CSSRule = @import("css_rule.zig").CSSRule;
-const CSSImportRule = @import("css_rule.zig").CSSImportRule;
-
-pub const CSSRuleList = struct {
-    list: std.ArrayListUnmanaged([]const u8),
-
-    pub fn constructor() CSSRuleList {
-        return .{ .list = .empty };
-    }
-
-    pub fn _item(self: *CSSRuleList, _index: u32) ?CSSRule {
-        const index: usize = @intCast(_index);
-
-        if (index > self.list.items.len) {
-            return null;
-        }
-
-        // todo: for now, just return null.
-        // this depends on properly parsing CSSRule
-        return null;
-    }
-
-    pub fn get_length(self: *CSSRuleList) u32 {
-        return @intCast(self.list.items.len);
-    }
-};
-
-const testing = @import("../../testing.zig");
-test "Browser.CSS.CSSRuleList" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let list = new CSSRuleList()", "undefined" },
-        .{ "list instanceof CSSRuleList", "true" },
-        .{ "list.length", "0" },
-        .{ "list.item(0)", "null" },
-    }, .{});
-}

src/browser/cssom/css_style_declaration.zig

@@ -1,241 +0,0 @@
-// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
-//
-// Francis Bouvier <francis@lightpanda.io>
-// Pierre Tachoire <pierre@lightpanda.io>
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Affero General Public License as
-// published by the Free Software Foundation, either version 3 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Affero General Public License for more details.
-//
-// You should have received a copy of the GNU Affero General Public License
-// along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-const std = @import("std");
-
-const CSSParser = @import("./css_parser.zig").CSSParser;
-const CSSValueAnalyzer = @import("./css_value_analyzer.zig").CSSValueAnalyzer;
-const CSSRule = @import("css_rule.zig").CSSRule;
-const Page = @import("../page.zig").Page;
-
-pub const CSSStyleDeclaration = struct {
-    store: std.StringHashMapUnmanaged(Property),
-    order: std.ArrayListUnmanaged([]const u8),
-
-    pub const empty: CSSStyleDeclaration = .{
-        .store = .empty,
-        .order = .empty,
-    };
-
-    const Property = struct {
-        value: []const u8,
-        priority: bool,
-    };
-
-    pub fn get_cssFloat(self: *const CSSStyleDeclaration) []const u8 {
-        return self._getPropertyValue("float");
-    }
-
-    pub fn set_cssFloat(self: *CSSStyleDeclaration, value: ?[]const u8, page: *Page) !void {
-        const final_value = value orelse "";
-        return self._setProperty("float", final_value, null, page);
-    }
-
-    pub fn get_cssText(self: *const CSSStyleDeclaration, page: *Page) ![]const u8 {
-        var buffer: std.ArrayListUnmanaged(u8) = .empty;
-        const writer = buffer.writer(page.call_arena);
-        for (self.order.items) |name| {
-            const prop = self.store.get(name).?;
-            const escaped = try CSSValueAnalyzer.escapeCSSValue(page.call_arena, prop.value);
-            try writer.print("{s}: {s}", .{ name, escaped });
-            if (prop.priority) try writer.writeAll(" !important");
-            try writer.writeAll("; ");
-        }
-        return buffer.items;
-    }
-
-    // TODO Propagate also upward to parent node
-    pub fn set_cssText(self: *CSSStyleDeclaration, text: []const u8, page: *Page) !void {
-        self.store.clearRetainingCapacity();
-        self.order.clearRetainingCapacity();
-
-        // call_arena is safe here, because _setProperty will dupe the name
-        // using the page's longer-living arena.
-        const declarations = try CSSParser.parseDeclarations(page.call_arena, text);
-
-        for (declarations) |decl| {
-            if (!CSSValueAnalyzer.isValidPropertyName(decl.name)) continue;
-            const priority: ?[]const u8 = if (decl.is_important) "important" else null;
-            try self._setProperty(decl.name, decl.value, priority, page);
-        }
-    }
-
-    pub fn get_length(self: *const CSSStyleDeclaration) usize {
-        return self.order.items.len;
-    }
-
-    pub fn get_parentRule(_: *const CSSStyleDeclaration) ?CSSRule {
-        return null;
-    }
-
-    pub fn _getPropertyPriority(self: *const CSSStyleDeclaration, name: []const u8) []const u8 {
-        return if (self.store.get(name)) |prop| (if (prop.priority) "important" else "") else "";
-    }
-
-    // TODO should handle properly shorthand properties and canonical forms
-    pub fn _getPropertyValue(self: *const CSSStyleDeclaration, name: []const u8) []const u8 {
-        if (self.store.get(name)) |prop| {
-            return prop.value;
-        }
-
-        // default to everything being visible (unless it's been explicitly set)
-        if (std.mem.eql(u8, name, "visibility")) {
-            return "visible";
-        }
-
-        return "";
-    }
-
-    pub fn _item(self: *const CSSStyleDeclaration, index: usize) []const u8 {
-        return if (index < self.order.items.len) self.order.items[index] else "";
-    }
-
-    pub fn _removeProperty(self: *CSSStyleDeclaration, name: []const u8) ![]const u8 {
-        const prop = self.store.fetchRemove(name) orelse return "";
-        for (self.order.items, 0..) |item, i| {
-            if (std.mem.eql(u8, item, name)) {
-                _ = self.order.orderedRemove(i);
-                break;
-            }
-        }
-        // safe to return, since it's in our page.arena
-        return prop.value.value;
-    }
-
-    pub fn _setProperty(self: *CSSStyleDeclaration, name: []const u8, value: []const u8, priority: ?[]const u8, page: *Page) !void {
-        const owned_value = try page.arena.dupe(u8, value);
-        const is_important = priority != null and std.ascii.eqlIgnoreCase(priority.?, "important");
-
-        const gop = try self.store.getOrPut(page.arena, name);
-        if (!gop.found_existing) {
-            const owned_name = try page.arena.dupe(u8, name);
-            gop.key_ptr.* = owned_name;
-            try self.order.append(page.arena, owned_name);
-        }
-
-        gop.value_ptr.* = .{ .value = owned_value, .priority = is_important };
-    }
-
-    pub fn named_get(self: *const CSSStyleDeclaration, name: []const u8, _: *bool) []const u8 {
-        return self._getPropertyValue(name);
-    }
-};
-
-const testing = @import("../../testing.zig");
-
-test "CSSOM.CSSStyleDeclaration" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let style = document.getElementById('content').style", "undefined" },
-        .{ "style.cssText = 'color: red; font-size: 12px; margin: 5px !important;'", "color: red; font-size: 12px; margin: 5px !important;" },
-        .{ "style.length", "3" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "style.getPropertyValue('color')", "red" },
-        .{ "style.getPropertyValue('font-size')", "12px" },
-        .{ "style.getPropertyValue('unknown-property')", "" },
-
-        .{ "style.getPropertyPriority('margin')", "important" },
-        .{ "style.getPropertyPriority('color')", "" },
-        .{ "style.getPropertyPriority('unknown-property')", "" },
-
-        .{ "style.item(0)", "color" },
-        .{ "style.item(1)", "font-size" },
-        .{ "style.item(2)", "margin" },
-        .{ "style.item(3)", "" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "style.setProperty('background-color', 'blue')", "undefined" },
-        .{ "style.getPropertyValue('background-color')", "blue" },
-        .{ "style.length", "4" },
-
-        .{ "style.setProperty('color', 'green')", "undefined" },
-        .{ "style.getPropertyValue('color')", "green" },
-        .{ "style.length", "4" },
-        .{ "style.color", "green" },
-
-        .{ "style.setProperty('padding', '10px', 'important')", "undefined" },
-        .{ "style.getPropertyValue('padding')", "10px" },
-        .{ "style.getPropertyPriority('padding')", "important" },
-
-        .{ "style.setProperty('border', '1px solid black', 'IMPORTANT')", "undefined" },
-        .{ "style.getPropertyPriority('border')", "important" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "style.removeProperty('color')", "green" },
-        .{ "style.getPropertyValue('color')", "" },
-        .{ "style.length", "5" },
-
-        .{ "style.removeProperty('unknown-property')", "" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "style.cssText.includes('font-size: 12px;')", "true" },
-        .{ "style.cssText.includes('margin: 5px !important;')", "true" },
-        .{ "style.cssText.includes('padding: 10px !important;')", "true" },
-        .{ "style.cssText.includes('border: 1px solid black !important;')", "true" },
-
-        .{ "style.cssText = 'color: purple; text-align: center;'", "color: purple; text-align: center;" },
-        .{ "style.length", "2" },
-        .{ "style.getPropertyValue('color')", "purple" },
-        .{ "style.getPropertyValue('text-align')", "center" },
-        .{ "style.getPropertyValue('font-size')", "" },
-
-        .{ "style.setProperty('cont', 'Hello; world!')", "undefined" },
-        .{ "style.getPropertyValue('cont')", "Hello; world!" },
-
-        .{ "style.cssText = 'content: \"Hello; world!\"; background-image: url(\"test.png\");'", "content: \"Hello; world!\"; background-image: url(\"test.png\");" },
-        .{ "style.getPropertyValue('content')", "\"Hello; world!\"" },
-        .{ "style.getPropertyValue('background-image')", "url(\"test.png\")" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "style.cssFloat", "" },
-        .{ "style.cssFloat = 'left'", "left" },
-        .{ "style.cssFloat", "left" },
-        .{ "style.getPropertyValue('float')", "left" },
-
-        .{ "style.cssFloat = 'right'", "right" },
-        .{ "style.cssFloat", "right" },
-
-        .{ "style.cssFloat = null", "null" },
-        .{ "style.cssFloat", "" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "style.setProperty('display', '')", "undefined" },
-        .{ "style.getPropertyValue('display')", "" },
-
-        .{ "style.cssText = '  color  :  purple  ;  margin  :  10px  ;  '", "  color  :  purple  ;  margin  :  10px  ;  " },
-        .{ "style.getPropertyValue('color')", "purple" },
-        .{ "style.getPropertyValue('margin')", "10px" },
-
-        .{ "style.setProperty('border-bottom-left-radius', '5px')", "undefined" },
-        .{ "style.getPropertyValue('border-bottom-left-radius')", "5px" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "style.visibility", "visible" },
-        .{ "style.getPropertyValue('visibility')", "visible" },
-    }, .{});
-}

src/browser/cssom/css_stylesheet.zig

@@ -1,91 +0,0 @@
-// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
-//
-// Francis Bouvier <francis@lightpanda.io>
-// Pierre Tachoire <pierre@lightpanda.io>
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Affero General Public License as
-// published by the Free Software Foundation, either version 3 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Affero General Public License for more details.
-//
-// You should have received a copy of the GNU Affero General Public License
-// along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-const std = @import("std");
-
-const Page = @import("../page.zig").Page;
-const StyleSheet = @import("stylesheet.zig").StyleSheet;
-
-const CSSRuleList = @import("css_rule_list.zig").CSSRuleList;
-const CSSImportRule = @import("css_rule.zig").CSSImportRule;
-
-pub const CSSStyleSheet = struct {
-    pub const prototype = *StyleSheet;
-
-    proto: StyleSheet,
-    css_rules: CSSRuleList,
-    owner_rule: ?*CSSImportRule,
-
-    const CSSStyleSheetOpts = struct {
-        base_url: ?[]const u8 = null,
-        // TODO: Suupport media
-        disabled: bool = false,
-    };
-
-    pub fn constructor(_opts: ?CSSStyleSheetOpts) !CSSStyleSheet {
-        const opts = _opts orelse CSSStyleSheetOpts{};
-        return .{
-            .proto = StyleSheet{ .disabled = opts.disabled },
-            .css_rules = .constructor(),
-            .owner_rule = null,
-        };
-    }
-
-    pub fn get_ownerRule(_: *CSSStyleSheet) ?*CSSImportRule {
-        return null;
-    }
-
-    pub fn get_cssRules(self: *CSSStyleSheet) *CSSRuleList {
-        return &self.css_rules;
-    }
-
-    pub fn _insertRule(self: *CSSStyleSheet, rule: []const u8, _index: ?usize, page: *Page) !usize {
-        const index = _index orelse 0;
-        if (index > self.css_rules.list.items.len) {
-            return error.IndexSize;
-        }
-
-        const arena = page.arena;
-        try self.css_rules.list.insert(arena, index, try arena.dupe(u8, rule));
-        return index;
-    }
-
-    pub fn _deleteRule(self: *CSSStyleSheet, index: usize) !void {
-        if (index > self.css_rules.list.items.len) {
-            return error.IndexSize;
-        }
-
-        _ = self.css_rules.list.orderedRemove(index);
-    }
-};
-
-const testing = @import("../../testing.zig");
-test "Browser.CSS.StyleSheet" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let css = new CSSStyleSheet()", "undefined" },
-        .{ "css instanceof CSSStyleSheet", "true" },
-        .{ "css.cssRules.length", "0" },
-        .{ "css.ownerRule", "null" },
-        .{ "let index1 = css.insertRule('body { color: red; }', 0)", "undefined" },
-        .{ "index1", "0" },
-        .{ "css.cssRules.length", "1" },
-    }, .{});
-}

src/browser/cssom/css_value_analyzer.zig

@@ -1,811 +0,0 @@
-// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
-//
-// Francis Bouvier <francis@lightpanda.io>
-// Pierre Tachoire <pierre@lightpanda.io>
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Affero General Public License as
-// published by the Free Software Foundation, either version 3 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Affero General Public License for more details.
-//
-// You should have received a copy of the GNU Affero General Public License
-// along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-const std = @import("std");
-
-pub const CSSValueAnalyzer = struct {
-    pub fn isNumericWithUnit(value: []const u8) bool {
-        if (value.len == 0) return false;
-
-        if (!std.ascii.isDigit(value[0]) and
-            value[0] != '+' and value[0] != '-' and value[0] != '.')
-        {
-            return false;
-        }
-
-        var i: usize = 0;
-        var has_digit = false;
-        var decimal_point = false;
-
-        while (i < value.len) : (i += 1) {
-            const c = value[i];
-            if (std.ascii.isDigit(c)) {
-                has_digit = true;
-            } else if (c == '.' and !decimal_point) {
-                decimal_point = true;
-            } else if ((c == 'e' or c == 'E') and has_digit) {
-                if (i + 1 >= value.len) return false;
-                if (value[i + 1] != '+' and value[i + 1] != '-' and !std.ascii.isDigit(value[i + 1])) break;
-                i += 1;
-                if (value[i] == '+' or value[i] == '-') {
-                    i += 1;
-                }
-                var has_exp_digits = false;
-                while (i < value.len and std.ascii.isDigit(value[i])) : (i += 1) {
-                    has_exp_digits = true;
-                }
-                if (!has_exp_digits) return false;
-                break;
-            } else if (c != '-' and c != '+') {
-                break;
-            }
-        }
-
-        if (!has_digit) return false;
-
-        if (i == value.len) return true;
-
-        const unit = value[i..];
-        return CSSKeywords.isValidUnit(unit);
-    }
-
-    pub fn isHexColor(value: []const u8) bool {
-        if (!std.mem.startsWith(u8, value, "#")) return false;
-
-        const hex_part = value[1..];
-        if (hex_part.len != 3 and hex_part.len != 6 and hex_part.len != 8) return false;
-
-        for (hex_part) |c| {
-            if (!std.ascii.isHex(c)) return false;
-        }
-
-        return true;
-    }
-
-    pub fn isMultiValueProperty(value: []const u8) bool {
-        var parts = std.mem.splitAny(u8, value, " ");
-        var multi_value_parts: usize = 0;
-        var all_parts_valid = true;
-
-        while (parts.next()) |part| {
-            if (part.len == 0) continue;
-            multi_value_parts += 1;
-
-            const is_numeric = isNumericWithUnit(part);
-            const is_hex_color = isHexColor(part);
-            const is_known_keyword = CSSKeywords.isKnownKeyword(part);
-            const is_function = CSSKeywords.startsWithFunction(part);
-
-            if (!is_numeric and !is_hex_color and !is_known_keyword and !is_function) {
-                all_parts_valid = false;
-                break;
-            }
-        }
-
-        return multi_value_parts >= 2 and all_parts_valid;
-    }
-
-    pub fn isAlreadyQuoted(value: []const u8) bool {
-        return value.len >= 2 and ((value[0] == '"' and value[value.len - 1] == '"') or
-            (value[0] == '\'' and value[value.len - 1] == '\''));
-    }
-
-    pub fn isValidPropertyName(name: []const u8) bool {
-        if (name.len == 0) return false;
-
-        if (std.mem.startsWith(u8, name, "--")) {
-            if (name.len == 2) return false;
-            for (name[2..]) |c| {
-                if (!std.ascii.isAlphanumeric(c) and c != '-' and c != '_') {
-                    return false;
-                }
-            }
-            return true;
-        }
-
-        const first_char = name[0];
-        if (!std.ascii.isAlphabetic(first_char) and first_char != '-') {
-            return false;
-        }
-
-        if (first_char == '-') {
-            if (name.len < 2) return false;
-
-            if (!std.ascii.isAlphabetic(name[1])) {
-                return false;
-            }
-
-            for (name[2..]) |c| {
-                if (!std.ascii.isAlphanumeric(c) and c != '-') {
-                    return false;
-                }
-            }
-        } else {
-            for (name[1..]) |c| {
-                if (!std.ascii.isAlphanumeric(c) and c != '-') {
-                    return false;
-                }
-            }
-        }
-
-        return true;
-    }
-
-    pub fn extractImportant(value: []const u8) struct { value: []const u8, is_important: bool } {
-        const trimmed = std.mem.trim(u8, value, &std.ascii.whitespace);
-
-        if (std.mem.endsWith(u8, trimmed, "!important")) {
-            const clean_value = std.mem.trimRight(u8, trimmed[0 .. trimmed.len - 10], &std.ascii.whitespace);
-            return .{ .value = clean_value, .is_important = true };
-        }
-
-        return .{ .value = trimmed, .is_important = false };
-    }
-
-    pub fn needsQuotes(value: []const u8) bool {
-        if (value.len == 0) return true;
-        if (isAlreadyQuoted(value)) return false;
-
-        if (CSSKeywords.containsSpecialChar(value)) {
-            return true;
-        }
-
-        if (std.mem.indexOfScalar(u8, value, ' ') == null) {
-            return false;
-        }
-
-        const is_url = std.mem.startsWith(u8, value, "url(");
-        const is_function = CSSKeywords.startsWithFunction(value);
-
-        return !isMultiValueProperty(value) and
-            !is_url and
-            !is_function;
-    }
-
-    pub fn escapeCSSValue(arena: std.mem.Allocator, value: []const u8) ![]const u8 {
-        if (!needsQuotes(value)) {
-            return value;
-        }
-        var out: std.ArrayListUnmanaged(u8) = .empty;
-
-        // We'll need at least this much space, +2 for the quotes
-        try out.ensureTotalCapacity(arena, value.len + 2);
-        const writer = out.writer(arena);
-
-        try writer.writeByte('"');
-
-        for (value, 0..) |c, i| {
-            switch (c) {
-                '"' => try writer.writeAll("\\\""),
-                '\\' => try writer.writeAll("\\\\"),
-                '\n' => try writer.writeAll("\\A "),
-                '\r' => try writer.writeAll("\\D "),
-                '\t' => try writer.writeAll("\\9 "),
-                0...8, 11, 12, 14...31, 127 => {
-                    try writer.print("\\{x}", .{c});
-                    if (i + 1 < value.len and std.ascii.isHex(value[i + 1])) {
-                        try writer.writeByte(' ');
-                    }
-                },
-                else => try writer.writeByte(c),
-            }
-        }
-
-        try writer.writeByte('"');
-        return out.items;
-    }
-
-    pub fn isKnownKeyword(value: []const u8) bool {
-        return CSSKeywords.isKnownKeyword(value);
-    }
-
-    pub fn containsSpecialChar(value: []const u8) bool {
-        return CSSKeywords.containsSpecialChar(value);
-    }
-};
-
-const CSSKeywords = struct {
-    const border_styles = [_][]const u8{
-        "none", "solid", "dotted", "dashed", "double", "groove", "ridge", "inset", "outset",
-    };
-
-    const color_names = [_][]const u8{
-        "black",        "white",   "red", "green", "blue", "yellow", "purple", "gray", "transparent",
-        "currentColor", "inherit",
-    };
-
-    const position_keywords = [_][]const u8{
-        "auto", "center", "left", "right", "top", "bottom",
-    };
-
-    const background_repeat = [_][]const u8{
-        "repeat", "no-repeat", "repeat-x", "repeat-y", "space", "round",
-    };
-
-    const font_styles = [_][]const u8{
-        "normal", "italic", "oblique", "bold", "bolder", "lighter",
-    };
-
-    const font_sizes = [_][]const u8{
-        "xx-small", "x-small", "small", "medium", "large", "x-large", "xx-large",
-        "smaller",  "larger",
-    };
-
-    const font_families = [_][]const u8{
-        "serif", "sans-serif", "monospace", "cursive", "fantasy", "system-ui",
-    };
-
-    const css_global = [_][]const u8{
-        "initial", "inherit", "unset", "revert",
-    };
-
-    const display_values = [_][]const u8{
-        "block", "inline", "inline-block", "flex", "grid", "none",
-    };
-
-    const length_units = [_][]const u8{
-        "px", "em", "rem", "vw", "vh", "vmin", "vmax", "%", "pt", "pc", "in", "cm", "mm",
-        "ex", "ch", "fr",
-    };
-
-    const angle_units = [_][]const u8{
-        "deg", "rad", "grad", "turn",
-    };
-
-    const time_units = [_][]const u8{
-        "s", "ms",
-    };
-
-    const frequency_units = [_][]const u8{
-        "Hz", "kHz",
-    };
-
-    const resolution_units = [_][]const u8{
-        "dpi", "dpcm", "dppx",
-    };
-
-    const special_chars = [_]u8{
-        '"', '\'', ';', '{', '}', '\\', '<', '>', '/', '\n', '\t', '\r', '\x00', '\x7F',
-    };
-
-    const functions = [_][]const u8{
-        "rgb(",             "rgba(",            "hsl(",            "hsla(",      "url(",    "calc(",  "var(",  "attr(",
-        "linear-gradient(", "radial-gradient(", "conic-gradient(", "translate(", "rotate(", "scale(", "skew(", "matrix(",
-    };
-
-    pub fn isKnownKeyword(value: []const u8) bool {
-        const all_categories = [_][]const []const u8{
-            &border_styles,  &color_names, &position_keywords, &background_repeat,
-            &font_styles,    &font_sizes,  &font_families,     &css_global,
-            &display_values,
-        };
-
-        for (all_categories) |category| {
-            for (category) |keyword| {
-                if (std.ascii.eqlIgnoreCase(value, keyword)) {
-                    return true;
-                }
-            }
-        }
-
-        return false;
-    }
-
-    pub fn containsSpecialChar(value: []const u8) bool {
-        for (value) |c| {
-            for (special_chars) |special| {
-                if (c == special) {
-                    return true;
-                }
-            }
-        }
-        return false;
-    }
-
-    pub fn isValidUnit(unit: []const u8) bool {
-        const all_units = [_][]const []const u8{
-            &length_units, &angle_units, &time_units, &frequency_units, &resolution_units,
-        };
-
-        for (all_units) |category| {
-            for (category) |valid_unit| {
-                if (std.ascii.eqlIgnoreCase(unit, valid_unit)) {
-                    return true;
-                }
-            }
-        }
-
-        return false;
-    }
-
-    pub fn startsWithFunction(value: []const u8) bool {
-        const pos = std.mem.indexOfScalar(u8, value, '(') orelse return false;
-        if (pos == 0) return false;
-
-        if (std.mem.indexOfScalarPos(u8, value, pos, ')') == null) {
-            return false;
-        }
-        const function_name = value[0..pos];
-        return isValidFunctionName(function_name);
-    }
-
-    fn isValidFunctionName(name: []const u8) bool {
-        if (name.len == 0) return false;
-
-        const first = name[0];
-        if (!std.ascii.isAlphabetic(first) and first != '_' and first != '-') {
-            return false;
-        }
-
-        for (name[1..]) |c| {
-            if (!std.ascii.isAlphanumeric(c) and c != '_' and c != '-') {
-                return false;
-            }
-        }
-
-        return true;
-    }
-};
-
-const testing = @import("../../testing.zig");
-
-test "CSSValueAnalyzer: isNumericWithUnit - valid numbers with units" {
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("10px"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("3.14em"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("-5rem"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("+12.5%"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("0vh"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit(".5vw"));
-}
-
-test "CSSValueAnalyzer: isNumericWithUnit - scientific notation" {
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("1e5px"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("2.5E-3em"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("1e+2rem"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("-3.14e10px"));
-}
-
-test "CSSValueAnalyzer: isNumericWithUnit - edge cases and invalid inputs" {
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit(""));
-
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("px"));
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("--px"));
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit(".px"));
-
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("1e"));
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("1epx"));
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("1e+"));
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("1e+px"));
-
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("1.2.3px"));
-
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("10xyz"));
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("5invalid"));
-
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("10"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("3.14"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("-5"));
-}
-
-test "CSSValueAnalyzer: isHexColor - valid hex colors" {
-    try testing.expect(CSSValueAnalyzer.isHexColor("#000"));
-    try testing.expect(CSSValueAnalyzer.isHexColor("#fff"));
-    try testing.expect(CSSValueAnalyzer.isHexColor("#123456"));
-    try testing.expect(CSSValueAnalyzer.isHexColor("#abcdef"));
-    try testing.expect(CSSValueAnalyzer.isHexColor("#ABCDEF"));
-    try testing.expect(CSSValueAnalyzer.isHexColor("#12345678"));
-}
-
-test "CSSValueAnalyzer: isHexColor - invalid hex colors" {
-    try testing.expect(!CSSValueAnalyzer.isHexColor(""));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("000"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#00"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#0000"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#00000"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#0000000"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#000000000"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#gggggg"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#123xyz"));
-}
-
-test "CSSValueAnalyzer: isMultiValueProperty - valid multi-value properties" {
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("10px 20px"));
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("solid red"));
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("#fff black"));
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("1em 2em 3em 4em"));
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("rgb(255,0,0) solid"));
-}
-
-test "CSSValueAnalyzer: isMultiValueProperty - invalid multi-value properties" {
-    try testing.expect(!CSSValueAnalyzer.isMultiValueProperty(""));
-    try testing.expect(!CSSValueAnalyzer.isMultiValueProperty("10px"));
-    try testing.expect(!CSSValueAnalyzer.isMultiValueProperty("invalid unknown"));
-    try testing.expect(!CSSValueAnalyzer.isMultiValueProperty("10px invalid"));
-    try testing.expect(!CSSValueAnalyzer.isMultiValueProperty("   "));
-}
-
-test "CSSValueAnalyzer: isAlreadyQuoted - various quoting scenarios" {
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("\"hello\""));
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("'world'"));
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("\"\""));
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("''"));
-
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted(""));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("hello"));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("\""));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("'"));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("\"hello'"));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("'hello\""));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("\"hello"));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("hello\""));
-}
-
-test "CSSValueAnalyzer: isValidPropertyName - valid property names" {
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("color"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("background-color"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("-webkit-transform"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("font-size"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("margin-top"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("z-index"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("line-height"));
-}
-
-test "CSSValueAnalyzer: isValidPropertyName - invalid property names" {
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName(""));
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName("123color"));
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName("color!"));
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName("color space"));
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName("@color"));
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName("color.test"));
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName("color_test"));
-}
-
-test "CSSValueAnalyzer: extractImportant - with and without !important" {
-    var result = CSSValueAnalyzer.extractImportant("red !important");
-    try testing.expect(result.is_important);
-    try testing.expectEqual("red", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("blue");
-    try testing.expect(!result.is_important);
-    try testing.expectEqual("blue", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("  green  !important  ");
-    try testing.expect(result.is_important);
-    try testing.expectEqual("green", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("!important");
-    try testing.expect(result.is_important);
-    try testing.expectEqual("", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("important");
-    try testing.expect(!result.is_important);
-    try testing.expectEqual("important", result.value);
-}
-
-test "CSSValueAnalyzer: needsQuotes - various scenarios" {
-    try testing.expect(CSSValueAnalyzer.needsQuotes(""));
-    try testing.expect(CSSValueAnalyzer.needsQuotes("hello world"));
-    try testing.expect(CSSValueAnalyzer.needsQuotes("test;"));
-    try testing.expect(CSSValueAnalyzer.needsQuotes("a{b}"));
-    try testing.expect(CSSValueAnalyzer.needsQuotes("test\"quote"));
-
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("\"already quoted\""));
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("'already quoted'"));
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("url(image.png)"));
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("rgb(255, 0, 0)"));
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("10px 20px"));
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("simple"));
-}
-
-test "CSSValueAnalyzer: escapeCSSValue - escaping various characters" {
-    const allocator = testing.arena_allocator;
-
-    var result = try CSSValueAnalyzer.escapeCSSValue(allocator, "simple");
-    try testing.expectEqual("simple", result);
-
-    result = try CSSValueAnalyzer.escapeCSSValue(allocator, "\"already quoted\"");
-    try testing.expectEqual("\"already quoted\"", result);
-
-    result = try CSSValueAnalyzer.escapeCSSValue(allocator, "test\"quote");
-    try testing.expectEqual("\"test\\\"quote\"", result);
-
-    result = try CSSValueAnalyzer.escapeCSSValue(allocator, "test\nline");
-    try testing.expectEqual("\"test\\A line\"", result);
-
-    result = try CSSValueAnalyzer.escapeCSSValue(allocator, "test\\back");
-    try testing.expectEqual("\"test\\\\back\"", result);
-}
-
-test "CSSValueAnalyzer: CSSKeywords.isKnownKeyword - case sensitivity" {
-    try testing.expect(CSSKeywords.isKnownKeyword("red"));
-    try testing.expect(CSSKeywords.isKnownKeyword("solid"));
-    try testing.expect(CSSKeywords.isKnownKeyword("center"));
-    try testing.expect(CSSKeywords.isKnownKeyword("inherit"));
-
-    try testing.expect(CSSKeywords.isKnownKeyword("RED"));
-    try testing.expect(CSSKeywords.isKnownKeyword("Red"));
-    try testing.expect(CSSKeywords.isKnownKeyword("SOLID"));
-    try testing.expect(CSSKeywords.isKnownKeyword("Center"));
-
-    try testing.expect(!CSSKeywords.isKnownKeyword("invalid"));
-    try testing.expect(!CSSKeywords.isKnownKeyword("unknown"));
-    try testing.expect(!CSSKeywords.isKnownKeyword(""));
-}
-
-test "CSSValueAnalyzer: CSSKeywords.containsSpecialChar - various special characters" {
-    try testing.expect(CSSKeywords.containsSpecialChar("test\"quote"));
-    try testing.expect(CSSKeywords.containsSpecialChar("test'quote"));
-    try testing.expect(CSSKeywords.containsSpecialChar("test;end"));
-    try testing.expect(CSSKeywords.containsSpecialChar("test{brace"));
-    try testing.expect(CSSKeywords.containsSpecialChar("test}brace"));
-    try testing.expect(CSSKeywords.containsSpecialChar("test\\back"));
-    try testing.expect(CSSKeywords.containsSpecialChar("test<angle"));
-    try testing.expect(CSSKeywords.containsSpecialChar("test>angle"));
-    try testing.expect(CSSKeywords.containsSpecialChar("test/slash"));
-
-    try testing.expect(!CSSKeywords.containsSpecialChar("normal-text"));
-    try testing.expect(!CSSKeywords.containsSpecialChar("text123"));
-    try testing.expect(!CSSKeywords.containsSpecialChar(""));
-}
-
-test "CSSValueAnalyzer: CSSKeywords.isValidUnit - various units" {
-    try testing.expect(CSSKeywords.isValidUnit("px"));
-    try testing.expect(CSSKeywords.isValidUnit("em"));
-    try testing.expect(CSSKeywords.isValidUnit("rem"));
-    try testing.expect(CSSKeywords.isValidUnit("%"));
-
-    try testing.expect(CSSKeywords.isValidUnit("deg"));
-    try testing.expect(CSSKeywords.isValidUnit("rad"));
-
-    try testing.expect(CSSKeywords.isValidUnit("s"));
-    try testing.expect(CSSKeywords.isValidUnit("ms"));
-
-    try testing.expect(CSSKeywords.isValidUnit("PX"));
-
-    try testing.expect(!CSSKeywords.isValidUnit("invalid"));
-    try testing.expect(!CSSKeywords.isValidUnit(""));
-}
-
-test "CSSValueAnalyzer: CSSKeywords.startsWithFunction - function detection" {
-    try testing.expect(CSSKeywords.startsWithFunction("rgb(255, 0, 0)"));
-    try testing.expect(CSSKeywords.startsWithFunction("rgba(255, 0, 0, 0.5)"));
-    try testing.expect(CSSKeywords.startsWithFunction("url(image.png)"));
-    try testing.expect(CSSKeywords.startsWithFunction("calc(100% - 20px)"));
-    try testing.expect(CSSKeywords.startsWithFunction("var(--custom-property)"));
-    try testing.expect(CSSKeywords.startsWithFunction("linear-gradient(to right, red, blue)"));
-
-    try testing.expect(CSSKeywords.startsWithFunction("custom-function(args)"));
-    try testing.expect(CSSKeywords.startsWithFunction("unknown(test)"));
-
-    try testing.expect(!CSSKeywords.startsWithFunction("not-a-function"));
-    try testing.expect(!CSSKeywords.startsWithFunction("missing-paren)"));
-    try testing.expect(!CSSKeywords.startsWithFunction("missing-close("));
-    try testing.expect(!CSSKeywords.startsWithFunction(""));
-    try testing.expect(!CSSKeywords.startsWithFunction("rgb"));
-}
-
-test "CSSValueAnalyzer: isNumericWithUnit - whitespace handling" {
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit(" 10px"));
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("10 px"));
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("10px "));
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit(" 10 px "));
-}
-
-test "CSSValueAnalyzer: extractImportant - whitespace edge cases" {
-    var result = CSSValueAnalyzer.extractImportant("   ");
-    try testing.expect(!result.is_important);
-    try testing.expectEqual("", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("\t\n\r !important\t\n");
-    try testing.expect(result.is_important);
-    try testing.expectEqual("", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("red\t!important");
-    try testing.expect(result.is_important);
-    try testing.expectEqual("red", result.value);
-}
-
-test "CSSValueAnalyzer: isHexColor - mixed case handling" {
-    try testing.expect(CSSValueAnalyzer.isHexColor("#AbC"));
-    try testing.expect(CSSValueAnalyzer.isHexColor("#123aBc"));
-    try testing.expect(CSSValueAnalyzer.isHexColor("#FFffFF"));
-    try testing.expect(CSSValueAnalyzer.isHexColor("#000FFF"));
-}
-
-test "CSSValueAnalyzer: edge case - very long inputs" {
-    const long_valid = "a" ** 1000 ++ "px";
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit(long_valid)); // not numeric
-
-    const long_property = "a-" ** 100 ++ "property";
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName(long_property));
-
-    const long_hex = "#" ++ "a" ** 20;
-    try testing.expect(!CSSValueAnalyzer.isHexColor(long_hex));
-}
-
-test "CSSValueAnalyzer: boundary conditions - numeric parsing" {
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("0px"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("0.0px"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit(".0px"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("0.px"));
-
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("999999999px"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("1.7976931348623157e+308px"));
-
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("0.000000001px"));
-    try testing.expect(CSSValueAnalyzer.isNumericWithUnit("1e-100px"));
-}
-
-test "CSSValueAnalyzer: extractImportant - malformed important declarations" {
-    var result = CSSValueAnalyzer.extractImportant("red ! important");
-    try testing.expect(!result.is_important);
-    try testing.expectEqual("red ! important", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("red !Important");
-    try testing.expect(!result.is_important);
-    try testing.expectEqual("red !Important", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("red !IMPORTANT");
-    try testing.expect(!result.is_important);
-    try testing.expectEqual("red !IMPORTANT", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("!importantred");
-    try testing.expect(!result.is_important);
-    try testing.expectEqual("!importantred", result.value);
-
-    result = CSSValueAnalyzer.extractImportant("red !important !important");
-    try testing.expect(result.is_important);
-    try testing.expectEqual("red !important", result.value);
-}
-
-test "CSSValueAnalyzer: isMultiValueProperty - complex spacing scenarios" {
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("10px    20px"));
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("solid     red"));
-
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("  10px 20px  "));
-
-    try testing.expect(!CSSValueAnalyzer.isMultiValueProperty("10px\t20px"));
-    try testing.expect(!CSSValueAnalyzer.isMultiValueProperty("10px\n20px"));
-
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("10px   20px   30px"));
-}
-
-test "CSSValueAnalyzer: isAlreadyQuoted - edge cases with quotes" {
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("\"'hello'\""));
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("'\"hello\"'"));
-
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("\"hello\\\"world\""));
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("'hello\\'world'"));
-
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("\"hello"));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("hello\""));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("'hello"));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("hello'"));
-
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("\"a\""));
-    try testing.expect(CSSValueAnalyzer.isAlreadyQuoted("'b'"));
-}
-
-test "CSSValueAnalyzer: needsQuotes - function and URL edge cases" {
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("rgb(255, 0, 0)"));
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("calc(100% - 20px)"));
-
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("url(path with spaces.jpg)"));
-
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("linear-gradient(to right, red, blue)"));
-
-    try testing.expect(CSSValueAnalyzer.needsQuotes("rgb(255, 0, 0"));
-}
-
-test "CSSValueAnalyzer: escapeCSSValue - control characters and Unicode" {
-    const allocator = testing.arena_allocator;
-
-    var result = try CSSValueAnalyzer.escapeCSSValue(allocator, "test\ttab");
-    try testing.expectEqual("\"test\\9 tab\"", result);
-
-    result = try CSSValueAnalyzer.escapeCSSValue(allocator, "test\rreturn");
-    try testing.expectEqual("\"test\\D return\"", result);
-
-    result = try CSSValueAnalyzer.escapeCSSValue(allocator, "test\x00null");
-    try testing.expectEqual("\"test\\0null\"", result);
-
-    result = try CSSValueAnalyzer.escapeCSSValue(allocator, "test\x7Fdel");
-    try testing.expectEqual("\"test\\7f del\"", result);
-
-    result = try CSSValueAnalyzer.escapeCSSValue(allocator, "test\"quote\nline\\back");
-    try testing.expectEqual("\"test\\\"quote\\A line\\\\back\"", result);
-}
-
-test "CSSValueAnalyzer: isValidPropertyName - CSS custom properties and vendor prefixes" {
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("--custom-color"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("--my-variable"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("--123"));
-
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("-webkit-transform"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("-moz-border-radius"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("-ms-filter"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("-o-transition"));
-
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName("-123invalid"));
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName("--"));
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName("-"));
-}
-
-test "CSSValueAnalyzer: startsWithFunction - case sensitivity and partial matches" {
-    try testing.expect(CSSKeywords.startsWithFunction("RGB(255, 0, 0)"));
-    try testing.expect(CSSKeywords.startsWithFunction("Rgb(255, 0, 0)"));
-    try testing.expect(CSSKeywords.startsWithFunction("URL(image.png)"));
-
-    try testing.expect(CSSKeywords.startsWithFunction("rg(something)"));
-    try testing.expect(CSSKeywords.startsWithFunction("ur(something)"));
-
-    try testing.expect(CSSKeywords.startsWithFunction("rgb(1,2,3)"));
-    try testing.expect(CSSKeywords.startsWithFunction("rgba(1,2,3,4)"));
-
-    try testing.expect(CSSKeywords.startsWithFunction("my-custom-function(args)"));
-    try testing.expect(CSSKeywords.startsWithFunction("function-with-dashes(test)"));
-
-    try testing.expect(!CSSKeywords.startsWithFunction("123function(test)"));
-}
-
-test "CSSValueAnalyzer: isHexColor - Unicode and invalid characters" {
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#ghijkl"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#12345g"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#xyz"));
-
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#АВС"));
-
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#1234567g"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("#g2345678"));
-}
-
-test "CSSValueAnalyzer: complex integration scenarios" {
-    const allocator = testing.arena_allocator;
-
-    try testing.expect(CSSValueAnalyzer.isMultiValueProperty("rgb(255,0,0) url(bg.jpg)"));
-
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("calc(100% - 20px)"));
-
-    const result = try CSSValueAnalyzer.escapeCSSValue(allocator, "fake(function with spaces");
-    try testing.expectEqual("\"fake(function with spaces\"", result);
-
-    const important_result = CSSValueAnalyzer.extractImportant("rgb(255,0,0) !important");
-    try testing.expect(important_result.is_important);
-    try testing.expectEqual("rgb(255,0,0)", important_result.value);
-}
-
-test "CSSValueAnalyzer: performance edge cases - empty and minimal inputs" {
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit(""));
-    try testing.expect(!CSSValueAnalyzer.isHexColor(""));
-    try testing.expect(!CSSValueAnalyzer.isMultiValueProperty(""));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted(""));
-    try testing.expect(!CSSValueAnalyzer.isValidPropertyName(""));
-    try testing.expect(CSSValueAnalyzer.needsQuotes(""));
-    try testing.expect(!CSSKeywords.isKnownKeyword(""));
-    try testing.expect(!CSSKeywords.containsSpecialChar(""));
-    try testing.expect(!CSSKeywords.isValidUnit(""));
-    try testing.expect(!CSSKeywords.startsWithFunction(""));
-
-    try testing.expect(!CSSValueAnalyzer.isNumericWithUnit("a"));
-    try testing.expect(!CSSValueAnalyzer.isHexColor("a"));
-    try testing.expect(!CSSValueAnalyzer.isMultiValueProperty("a"));
-    try testing.expect(!CSSValueAnalyzer.isAlreadyQuoted("a"));
-    try testing.expect(CSSValueAnalyzer.isValidPropertyName("a"));
-    try testing.expect(!CSSValueAnalyzer.needsQuotes("a"));
-}

src/browser/cssom/cssom.zig

@@ -16,15 +16,10 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-pub const Stylesheet = @import("stylesheet.zig").StyleSheet;
-pub const CSSStylesheet = @import("css_stylesheet.zig").CSSStyleSheet;
-pub const CSSStyleDeclaration = @import("css_style_declaration.zig").CSSStyleDeclaration;
-pub const CSSRuleList = @import("css_rule_list.zig").CSSRuleList;
-
 pub const Interfaces = .{
-    Stylesheet,
-    CSSStylesheet,
-    CSSStyleDeclaration,
-    CSSRuleList,
-    @import("css_rule.zig").Interfaces,
+    @import("StyleSheet.zig"),
+    @import("CSSStyleSheet.zig"),
+    @import("CSSStyleDeclaration.zig"),
+    @import("CSSRuleList.zig"),
+    @import("CSSRule.zig").Interfaces,
 };

src/browser/datauri.zig

@@ -1,79 +0,0 @@
-const std = @import("std");
-const Allocator = std.mem.Allocator;
-
-// Represents https://developer.mozilla.org/en-US/docs/Web/URI/Reference/Schemes/data
-pub const DataURI = struct {
-    was_base64_encoded: bool,
-    // The contents in the uri. It will be base64 decoded but not prepared in
-    // any way for mime.charset.
-    data: []const u8,
-
-    // Parses data:[<media-type>][;base64],<data>
-    pub fn parse(allocator: Allocator, src: []const u8) !?DataURI {
-        if (!std.mem.startsWith(u8, src, "data:")) {
-            return null;
-        }
-
-        const uri = src[5..];
-        const data_starts = std.mem.indexOfScalar(u8, uri, ',') orelse return null;
-
-        // Extract the encoding.
-        var metadata = uri[0..data_starts];
-        var base64_encoded = false;
-        if (std.mem.endsWith(u8, metadata, ";base64")) {
-            base64_encoded = true;
-            metadata = metadata[0 .. metadata.len - 7];
-        }
-
-        // TODO: Extract mime type. This not trivial because Mime.parse requires
-        // a []u8 and might mutate the src. And, the DataURI.parse references atm
-        // do not have deinit calls.
-
-        // Prepare the data.
-        var data = uri[data_starts + 1 ..];
-        if (base64_encoded) {
-            const decoder = std.base64.standard.Decoder;
-            const decoded_size = try decoder.calcSizeForSlice(data);
-
-            const buffer = try allocator.alloc(u8, decoded_size);
-            errdefer allocator.free(buffer);
-
-            try decoder.decode(buffer, data);
-            data = buffer;
-        }
-
-        return .{
-            .was_base64_encoded = base64_encoded,
-            .data = data,
-        };
-    }
-
-    pub fn deinit(self: *const DataURI, allocator: Allocator) void {
-        if (self.was_base64_encoded) {
-            allocator.free(self.data);
-        }
-    }
-};
-
-const testing = std.testing;
-test "DataURI: parse valid" {
-    try test_valid("data:text/javascript; charset=utf-8;base64,Zm9v", "foo");
-    try test_valid("data:text/javascript; charset=utf-8;,foo", "foo");
-    try test_valid("data:,foo", "foo");
-}
-
-test "DataURI: parse invalid" {
-    try test_cannot_parse("atad:,foo");
-    try test_cannot_parse("data:foo");
-    try test_cannot_parse("data:");
-}
-
-fn test_valid(uri: []const u8, expected: []const u8) !void {
-    const data_uri = try DataURI.parse(std.testing.allocator, uri) orelse return error.TestFailed;
-    defer data_uri.deinit(testing.allocator);
-    try testing.expectEqualStrings(expected, data_uri.data);
-}
-
-fn test_cannot_parse(uri: []const u8) !void {
-    try testing.expectEqual(null, DataURI.parse(std.testing.allocator, uri));
-}

src/browser/dom/Animation.zig

@@ -0,0 +1,109 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const Page = @import("../page.zig").Page;
+const JsObject = @import("../env.zig").JsObject;
+const Promise = @import("../env.zig").Promise;
+const PromiseResolver = @import("../env.zig").PromiseResolver;
+
+const Animation = @This();
+
+effect: ?JsObject,
+timeline: ?JsObject,
+ready_resolver: ?PromiseResolver,
+finished_resolver: ?PromiseResolver,
+
+pub fn constructor(effect: ?JsObject, timeline: ?JsObject) !Animation {
+    return .{
+        .effect = if (effect) |eo| try eo.persist() else null,
+        .timeline = if (timeline) |to| try to.persist() else null,
+        .ready_resolver = null,
+        .finished_resolver = null,
+    };
+}
+
+pub fn get_playState(self: *const Animation) []const u8 {
+    _ = self;
+    return "finished";
+}
+
+pub fn get_pending(self: *const Animation) bool {
+    _ = self;
+    return false;
+}
+
+pub fn get_finished(self: *Animation, page: *Page) !Promise {
+    if (self.finished_resolver == null) {
+        const resolver = page.main_context.createPromiseResolver();
+        try resolver.resolve(self);
+        self.finished_resolver = resolver;
+    }
+    return self.finished_resolver.?.promise();
+}
+
+pub fn get_ready(self: *Animation, page: *Page) !Promise {
+    // never resolved, because we're always "finished"
+    if (self.ready_resolver == null) {
+        const resolver = page.main_context.createPromiseResolver();
+        self.ready_resolver = resolver;
+    }
+    return self.ready_resolver.?.promise();
+}
+
+pub fn get_effect(self: *const Animation) ?JsObject {
+    return self.effect;
+}
+
+pub fn set_effect(self: *Animation, effect: JsObject) !void {
+    self.effect = try effect.persist();
+}
+
+pub fn get_timeline(self: *const Animation) ?JsObject {
+    return self.timeline;
+}
+
+pub fn set_timeline(self: *Animation, timeline: JsObject) !void {
+    self.timeline = try timeline.persist();
+}
+
+pub fn _play(self: *const Animation) void {
+    _ = self;
+}
+
+pub fn _pause(self: *const Animation) void {
+    _ = self;
+}
+
+pub fn _cancel(self: *const Animation) void {
+    _ = self;
+}
+
+pub fn _finish(self: *const Animation) void {
+    _ = self;
+}
+
+pub fn _reverse(self: *const Animation) void {
+    _ = self;
+}
+
+const testing = @import("../../testing.zig");
+test "Browser: DOM.Animation" {
+    try testing.htmlRunner("dom/animation.html");
+}

src/browser/dom/MessageChannel.zig

@@ -0,0 +1,291 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+const log = @import("../../log.zig");
+const parser = @import("../netsurf.zig");
+
+const Env = @import("../env.zig").Env;
+const Page = @import("../page.zig").Page;
+const EventTarget = @import("../dom/event_target.zig").EventTarget;
+const EventHandler = @import("../events/event.zig").EventHandler;
+
+const JsObject = Env.JsObject;
+const Function = Env.Function;
+const Allocator = std.mem.Allocator;
+
+const MAX_QUEUE_SIZE = 10;
+
+pub const Interfaces = .{ MessageChannel, MessagePort };
+
+const MessageChannel = @This();
+
+port1: *MessagePort,
+port2: *MessagePort,
+
+pub fn constructor(page: *Page) !MessageChannel {
+    // Why do we allocate this rather than storing directly in the struct?
+    // https://github.com/lightpanda-io/project/discussions/165
+    const port1 = try page.arena.create(MessagePort);
+    const port2 = try page.arena.create(MessagePort);
+    port1.* = .{
+        .pair = port2,
+    };
+    port2.* = .{
+        .pair = port1,
+    };
+
+    return .{
+        .port1 = port1,
+        .port2 = port2,
+    };
+}
+
+pub fn get_port1(self: *const MessageChannel) *MessagePort {
+    return self.port1;
+}
+
+pub fn get_port2(self: *const MessageChannel) *MessagePort {
+    return self.port2;
+}
+
+pub const MessagePort = struct {
+    pub const prototype = *EventTarget;
+
+    proto: parser.EventTargetTBase = .{ .internal_target_type = .message_port },
+
+    pair: *MessagePort,
+    closed: bool = false,
+    started: bool = false,
+    onmessage_cbk: ?Function = null,
+    onmessageerror_cbk: ?Function = null,
+    // This is the queue of messages to dispatch to THIS MessagePort when the
+    // MessagePort is started.
+    queue: std.ArrayListUnmanaged(JsObject) = .empty,
+
+    pub const PostMessageOption = union(enum) {
+        transfer: JsObject,
+        options: Opts,
+
+        pub const Opts = struct {
+            transfer: JsObject,
+        };
+    };
+
+    pub fn _postMessage(self: *MessagePort, obj: JsObject, opts_: ?PostMessageOption, page: *Page) !void {
+        if (self.closed) {
+            return;
+        }
+
+        if (opts_ != null) {
+            log.warn(.web_api, "not implemented", .{ .feature = "MessagePort postMessage options" });
+            return error.NotImplemented;
+        }
+
+        try self.pair.dispatchOrQueue(obj, page.arena);
+    }
+
+    // Start impacts the ability to receive a message.
+    // Given pair1 (started) and pair2 (not started), then:
+    //    pair2.postMessage('x'); //will be dispatched to pair1.onmessage
+    //    pair1.postMessage('x'); // will be queued until pair2 is started
+    pub fn _start(self: *MessagePort) !void {
+        if (self.started) {
+            return;
+        }
+        self.started = true;
+        for (self.queue.items) |data| {
+            try self.dispatch(data);
+        }
+        // we'll never use this queue again, but it's allocated with an arena
+        // we don't even need to clear it, but it seems a bit safer to do at
+        // least that
+        self.queue.clearRetainingCapacity();
+    }
+
+    // Closing seems to stop both the publishing and receiving of messages,
+    // effectively rendering the channel useless. It cannot be reversed.
+    pub fn _close(self: *MessagePort) void {
+        self.closed = true;
+        self.pair.closed = true;
+    }
+
+    pub fn get_onmessage(self: *MessagePort) ?Function {
+        return self.onmessage_cbk;
+    }
+    pub fn get_onmessageerror(self: *MessagePort) ?Function {
+        return self.onmessageerror_cbk;
+    }
+
+    pub fn set_onmessage(self: *MessagePort, listener: EventHandler.Listener, page: *Page) !void {
+        if (self.onmessage_cbk) |cbk| {
+            try self.unregister("message", cbk.id);
+        }
+        self.onmessage_cbk = try self.register(page.arena, "message", listener);
+
+        // When onmessage is set directly, then it's like start() was called.
+        // If addEventListener('message') is used, the app has to call start()
+        // explicitly.
+        try self._start();
+    }
+
+    pub fn set_onmessageerror(self: *MessagePort, listener: EventHandler.Listener, page: *Page) !void {
+        if (self.onmessageerror_cbk) |cbk| {
+            try self.unregister("messageerror", cbk.id);
+        }
+        self.onmessageerror_cbk = try self.register(page.arena, "messageerror", listener);
+    }
+
+    // called from our pair. If port1.postMessage("x") is called, then this
+    // will be called on port2.
+    fn dispatchOrQueue(self: *MessagePort, obj: JsObject, arena: Allocator) !void {
+        // our pair should have checked this already
+        std.debug.assert(self.closed == false);
+
+        if (self.started) {
+            return self.dispatch(try obj.persist());
+        }
+
+        if (self.queue.items.len > MAX_QUEUE_SIZE) {
+            // This isn't part of the spec, but not putting a limit is reckless
+            return error.MessageQueueLimit;
+        }
+        return self.queue.append(arena, try obj.persist());
+    }
+
+    fn dispatch(self: *MessagePort, obj: JsObject) !void {
+        // obj is already persisted, don't use `MessageEvent.constructor`, but
+        // go directly to `init`, which assumes persisted objects.
+        var evt = try MessageEvent.init(.{ .data = obj });
+        _ = try parser.eventTargetDispatchEvent(
+            parser.toEventTarget(MessagePort, self),
+            @as(*parser.Event, @ptrCast(&evt)),
+        );
+    }
+
+    fn register(
+        self: *MessagePort,
+        alloc: Allocator,
+        typ: []const u8,
+        listener: EventHandler.Listener,
+    ) !?Function {
+        const target = @as(*parser.EventTarget, @ptrCast(self));
+        const eh = (try EventHandler.register(alloc, target, typ, listener, null)) orelse unreachable;
+        return eh.callback;
+    }
+
+    fn unregister(self: *MessagePort, typ: []const u8, cbk_id: usize) !void {
+        const et = @as(*parser.EventTarget, @ptrCast(self));
+        const lst = try parser.eventTargetHasListener(et, typ, false, cbk_id);
+        if (lst == null) {
+            return;
+        }
+        try parser.eventTargetRemoveEventListener(et, typ, lst.?, false);
+    }
+};
+
+pub const MessageEvent = struct {
+    const Event = @import("../events/event.zig").Event;
+    const DOMException = @import("exceptions.zig").DOMException;
+
+    pub const prototype = *Event;
+    pub const Exception = DOMException;
+    pub const union_make_copy = true;
+
+    proto: parser.Event,
+    data: ?JsObject,
+
+    // You would think if port1 sends to port2, the source would be port2
+    // (which is how I read the documentation), but it appears to always be
+    // null. It can always be set explicitly via the constructor;
+    source: ?JsObject,
+
+    origin: []const u8,
+
+    // This is used for Server-Sent events. Appears to always be an empty
+    // string for MessagePort messages.
+    last_event_id: []const u8,
+
+    // This might be related to the "transfer" option of postMessage which
+    // we don't yet support. For "normal" message, it's always an empty array.
+    // Though it could be set explicitly via the constructor
+    ports: []*MessagePort,
+
+    const Options = struct {
+        data: ?JsObject = null,
+        source: ?JsObject = null,
+        origin: []const u8 = "",
+        lastEventId: []const u8 = "",
+        ports: []*MessagePort = &.{},
+    };
+
+    pub fn constructor(opts: Options) !MessageEvent {
+        return init(.{
+            .data = if (opts.data) |obj| try obj.persist() else null,
+            .source = if (opts.source) |obj| try obj.persist() else null,
+            .ports = opts.ports,
+            .origin = opts.origin,
+            .lastEventId = opts.lastEventId,
+        });
+    }
+
+    // This is like "constructor", but it assumes JsObjects have already been
+    // persisted. Necessary because this `new MessageEvent()` can be called
+    // directly from JS OR from a port.postMessage. In the latter case, data
+    // may have already been persisted (as it might need to be queued);
+    fn init(opts: Options) !MessageEvent {
+        const event = try parser.eventCreate();
+        defer parser.eventDestroy(event);
+        try parser.eventInit(event, "message", .{});
+        try parser.eventSetInternalType(event, .message_event);
+
+        return .{
+            .proto = event.*,
+            .data = opts.data,
+            .source = opts.source,
+            .ports = opts.ports,
+            .origin = opts.origin,
+            .last_event_id = opts.lastEventId,
+        };
+    }
+
+    pub fn get_data(self: *const MessageEvent) !?JsObject {
+        return self.data;
+    }
+
+    pub fn get_origin(self: *const MessageEvent) []const u8 {
+        return self.origin;
+    }
+
+    pub fn get_source(self: *const MessageEvent) ?JsObject {
+        return self.source;
+    }
+
+    pub fn get_ports(self: *const MessageEvent) []*MessagePort {
+        return self.ports;
+    }
+
+    pub fn get_lastEventId(self: *const MessageEvent) []const u8 {
+        return self.last_event_id;
+    }
+};
+
+const testing = @import("../../testing.zig");
+test "Browser: DOM.MessageChannel" {
+    try testing.htmlRunner("dom/message_channel.html");
+}

src/browser/dom/attribute.zig

@@ -15,7 +15,6 @@
 //
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
 const parser = @import("../netsurf.zig");
 
 const Node = @import("node.zig").Node;
@@ -47,7 +46,14 @@ pub const Attr = struct {
     }
 
     pub fn set_value(self: *parser.Attribute, v: []const u8) !?[]const u8 {
-        try parser.attributeSetValue(self, v);
+        if (try parser.attributeGetOwnerElement(self)) |el| {
+            // if possible, go through the element, as that triggers a
+            // DOMAttrModified event (which MutationObserver cares about)
+            const name = try parser.attributeGetName(self);
+            try parser.elementSetAttribute(el, name, v);
+        } else {
+            try parser.attributeSetValue(self, v);
+        }
         return v;
     }
 
@@ -64,32 +70,6 @@ pub const Attr = struct {
 // -----
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.Attribute" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let a = document.createAttributeNS('foo', 'bar')", "undefined" },
-        .{ "a.namespaceURI", "foo" },
-        .{ "a.prefix", "null" },
-        .{ "a.localName", "bar" },
-        .{ "a.name", "bar" },
-        .{ "a.value", "" },
-        // TODO: libdom has a bug here: the created attr has no parent, it
-        // causes a panic w/ libdom when setting the value.
-        //.{ "a.value = 'nok'", "nok" },
-        .{ "a.ownerElement", "null" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let b = document.getElementById('link').getAttributeNode('class')", "undefined" },
-        .{ "b.name", "class" },
-        .{ "b.value", "ok" },
-        .{ "b.value = 'nok'", "nok" },
-        .{ "b.value", "nok" },
-        .{ "b.value = null", "null" },
-        .{ "b.value", "null" },
-        .{ "b.value = 'ok'", "ok" },
-        .{ "b.ownerElement.id", "link" },
-    }, .{});
+test "Browser: DOM.Attribute" {
+    try testing.htmlRunner("dom/attribute.html");
 }

src/browser/dom/character_data.zig

@@ -24,7 +24,8 @@ const Node = @import("node.zig").Node;
 const Comment = @import("comment.zig").Comment;
 const Text = @import("text.zig");
 const ProcessingInstruction = @import("processing_instruction.zig").ProcessingInstruction;
-const HTMLElem = @import("../html/elements.zig");
+const Element = @import("element.zig").Element;
+const ElementUnion = @import("element.zig").Union;
 
 // CharacterData interfaces
 pub const Interfaces = .{
@@ -49,20 +50,20 @@ pub const CharacterData = struct {
         return try parser.characterDataLength(self);
     }
 
-    pub fn get_nextElementSibling(self: *parser.CharacterData) !?HTMLElem.Union {
+    pub fn get_nextElementSibling(self: *parser.CharacterData) !?ElementUnion {
         const res = try parser.nodeNextElementSibling(parser.characterDataToNode(self));
         if (res == null) {
             return null;
         }
-        return try HTMLElem.toInterface(HTMLElem.Union, res.?);
+        return try Element.toInterface(res.?);
     }
 
-    pub fn get_previousElementSibling(self: *parser.CharacterData) !?HTMLElem.Union {
+    pub fn get_previousElementSibling(self: *parser.CharacterData) !?ElementUnion {
         const res = try parser.nodePreviousElementSibling(parser.characterDataToNode(self));
         if (res == null) {
             return null;
         }
-        return try HTMLElem.toInterface(HTMLElem.Union, res.?);
+        return try Element.toInterface(res.?);
     }
 
     // Read/Write attributes
@@ -101,7 +102,7 @@ pub const CharacterData = struct {
     // netsurf's CharacterData (text, comment) doesn't implement the
     // dom_node_get_attributes and thus will crash if we try to call nodeIsEqualNode.
     pub fn _isEqualNode(self: *parser.CharacterData, other_node: *parser.Node) !bool {
-        if (try parser.nodeType(@alignCast(@ptrCast(self))) != try parser.nodeType(other_node)) {
+        if (try parser.nodeType(@ptrCast(@alignCast(self))) != try parser.nodeType(other_node)) {
             return false;
         }
 
@@ -128,69 +129,6 @@ pub const CharacterData = struct {
 // -----
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.CharacterData" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let link = document.getElementById('link')", "undefined" },
-        .{ "let cdata = link.firstChild", "undefined" },
-        .{ "cdata.data", "OK" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.data = 'OK modified'", "OK modified" },
-        .{ "cdata.data === 'OK modified'", "true" },
-        .{ "cdata.data = 'OK'", "OK" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.length === 2", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.nextElementSibling === null", "true" },
-        // create a next element
-        .{ "let next = document.createElement('a')", "undefined" },
-        .{ "link.appendChild(next, cdata) !== undefined", "true" },
-        .{ "cdata.nextElementSibling.localName === 'a' ", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.previousElementSibling === null", "true" },
-        // create a prev element
-        .{ "let prev = document.createElement('div')", "undefined" },
-        .{ "link.insertBefore(prev, cdata) !== undefined", "true" },
-        .{ "cdata.previousElementSibling.localName === 'div' ", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.appendData(' modified')", "undefined" },
-        .{ "cdata.data === 'OK modified' ", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.deleteData('OK'.length, ' modified'.length)", "undefined" },
-        .{ "cdata.data == 'OK'", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.insertData('OK'.length-1, 'modified')", "undefined" },
-        .{ "cdata.data == 'OmodifiedK'", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.replaceData('OK'.length-1, 'modified'.length, 'replaced')", "undefined" },
-        .{ "cdata.data == 'OreplacedK'", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.substringData('OK'.length-1, 'replaced'.length) == 'replaced'", "true" },
-        .{ "cdata.substringData('OK'.length-1, 0) == ''", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "cdata.substringData('OK'.length-1, 'replaced'.length) == 'replaced'", "true" },
-        .{ "cdata.substringData('OK'.length-1, 0) == ''", "true" },
-    }, .{});
+test "Browser: DOM.CharacterData" {
+    try testing.htmlRunner("dom/character_data.html");
 }

src/browser/dom/comment.zig

@@ -40,15 +40,6 @@ pub const Comment = struct {
 // -----
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.Comment" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let comment = new Comment('foo')", "undefined" },
-        .{ "comment.data", "foo" },
-
-        .{ "let emptycomment = new Comment()", "undefined" },
-        .{ "emptycomment.data", "" },
-    }, .{});
+test "Browser: DOM.Comment" {
+    try testing.htmlRunner("dom/comment.html");
 }

src/browser/dom/css.zig

@@ -38,7 +38,7 @@ pub fn querySelector(alloc: std.mem.Allocator, n: *parser.Node, selector: []cons
 
     var m = MatchFirst{};
 
-    _ = try css.matchFirst(ps, Node{ .node = n }, &m);
+    _ = try css.matchFirst(&ps, Node{ .node = n }, &m);
     return m.n;
 }
 
@@ -75,6 +75,6 @@ pub fn querySelectorAll(alloc: std.mem.Allocator, n: *parser.Node, selector: []c
     var m = MatchAll.init(alloc);
     defer m.deinit();
 
-    try css.matchAll(ps, Node{ .node = n }, &m);
+    try css.matchAll(&ps, Node{ .node = n }, &m);
     return m.toOwnedList();
 }

src/browser/dom/document.zig

@@ -32,6 +32,11 @@ const css = @import("css.zig");
 const Element = @import("element.zig").Element;
 const ElementUnion = @import("element.zig").Union;
 const TreeWalker = @import("tree_walker.zig").TreeWalker;
+const CSSStyleSheet = @import("../cssom/CSSStyleSheet.zig");
+const NodeIterator = @import("node_iterator.zig").NodeIterator;
+const Range = @import("range.zig").Range;
+
+const CustomEvent = @import("../events/custom_event.zig").CustomEvent;
 
 const Env = @import("../env.zig").Env;
 
@@ -107,13 +112,21 @@ pub const Document = struct {
         return try parser.documentGetDoctype(self);
     }
 
-    pub fn _createEvent(_: *parser.Document, eventCstr: []const u8) !*parser.Event {
-        // TODO: for now only "Event" constructor is supported
-        // see table on https://dom.spec.whatwg.org/#dom-document-createevent $2
+    pub fn _createEvent(_: *parser.Document, eventCstr: []const u8) !union(enum) {
+        base: *parser.Event,
+        custom: CustomEvent,
+    } {
         if (std.ascii.eqlIgnoreCase(eventCstr, "Event") or std.ascii.eqlIgnoreCase(eventCstr, "Events")) {
-            return try parser.eventCreate();
+            return .{ .base = try parser.eventCreate() };
         }
-        return parser.DOMError.NotSupported;
+
+        // Not documented in MDN but supported in Chrome.
+        // This is actually both instance of `Event` and `CustomEvent`.
+        if (std.ascii.eqlIgnoreCase(eventCstr, "CustomEvent")) {
+            return .{ .custom = try CustomEvent.constructor(eventCstr, null) };
+        }
+
+        return error.NotSupported;
     }
 
     pub fn _getElementById(self: *parser.Document, id: []const u8) !?ElementUnion {
@@ -121,28 +134,11 @@ pub const Document = struct {
         return try Element.toInterface(e);
     }
 
-    const CreateElementResult = union(enum) {
-        element: ElementUnion,
-        custom: Env.JsObject,
-    };
-
-    pub fn _createElement(self: *parser.Document, tag_name: []const u8, page: *Page) !CreateElementResult {
-        const custom_element = page.window.custom_elements._get(tag_name) orelse {
-            const e = try parser.documentCreateElement(self, tag_name);
-            return .{ .element = try Element.toInterface(e) };
-        };
-
-        var result: Env.Function.Result = undefined;
-        const js_obj = custom_element.newInstance(&result) catch |err| {
-            log.fatal(.user_script, "newInstance error", .{
-                .err = result.exception,
-                .stack = result.stack,
-                .tag_name = tag_name,
-                .source = "createElement",
-            });
-            return err;
-        };
-        return .{ .custom = js_obj };
+    pub fn _createElement(self: *parser.Document, tag_name: []const u8) !ElementUnion {
+        // The element’s namespace is the HTML namespace when document is an HTML document
+        // https://dom.spec.whatwg.org/#ref-for-dom-document-createelement%E2%91%A0
+        const e = try parser.documentCreateElementNS(self, "http://www.w3.org/1999/xhtml", tag_name);
+        return Element.toInterface(e);
     }
 
     pub fn _createElementNS(self: *parser.Document, ns: []const u8, tag_name: []const u8) !ElementUnion {
@@ -163,7 +159,9 @@ pub const Document = struct {
         tag_name: []const u8,
         page: *Page,
     ) !collection.HTMLCollection {
-        return try collection.HTMLCollectionByTagName(page.arena, parser.documentToNode(self), tag_name, true);
+        return try collection.HTMLCollectionByTagName(page.arena, parser.documentToNode(self), tag_name, .{
+            .include_root = true,
+        });
     }
 
     pub fn _getElementsByClassName(
@@ -171,7 +169,9 @@ pub const Document = struct {
         classNames: []const u8,
         page: *Page,
     ) !collection.HTMLCollection {
-        return try collection.HTMLCollectionByClassName(page.arena, parser.documentToNode(self), classNames, true);
+        return try collection.HTMLCollectionByClassName(page.arena, parser.documentToNode(self), classNames, .{
+            .include_root = true,
+        });
     }
 
     pub fn _createDocumentFragment(self: *parser.Document) !*parser.DocumentFragment {
@@ -215,7 +215,9 @@ pub const Document = struct {
     // ParentNode
     // https://dom.spec.whatwg.org/#parentnode
     pub fn get_children(self: *parser.Document) !collection.HTMLCollection {
-        return try collection.HTMLCollectionChildren(parser.documentToNode(self), false);
+        return collection.HTMLCollectionChildren(parser.documentToNode(self), .{
+            .include_root = false,
+        });
     }
 
     pub fn get_firstElementChild(self: *parser.Document) !?ElementUnion {
@@ -236,7 +238,7 @@ pub const Document = struct {
     pub fn _querySelector(self: *parser.Document, selector: []const u8, page: *Page) !?ElementUnion {
         if (selector.len == 0) return null;
 
-        const n = try css.querySelector(page.arena, parser.documentToNode(self), selector);
+        const n = try css.querySelector(page.call_arena, parser.documentToNode(self), selector);
 
         if (n == null) return null;
 
@@ -259,19 +261,23 @@ pub const Document = struct {
         return Node.replaceChildren(parser.documentToNode(self), nodes);
     }
 
-    pub fn _createTreeWalker(_: *parser.Document, root: *parser.Node, what_to_show: ?u32, filter: ?TreeWalker.TreeWalkerOpts) !TreeWalker {
-        return try TreeWalker.init(root, what_to_show, filter);
+    pub fn _createTreeWalker(_: *parser.Document, root: *parser.Node, what_to_show: ?TreeWalker.WhatToShow, filter: ?TreeWalker.TreeWalkerOpts) !TreeWalker {
+        return TreeWalker.init(root, what_to_show, filter);
+    }
+
+    pub fn _createNodeIterator(_: *parser.Document, root: *parser.Node, what_to_show: ?NodeIterator.WhatToShow, filter: ?NodeIterator.NodeIteratorOpts) !NodeIterator {
+        return NodeIterator.init(root, what_to_show, filter);
     }
 
     pub fn getActiveElement(self: *parser.Document, page: *Page) !?*parser.Element {
-        if (page.getNodeState(@alignCast(@ptrCast(self)))) |state| {
+        if (page.getNodeState(@ptrCast(@alignCast(self)))) |state| {
             if (state.active_element) |ae| {
                 return ae;
             }
         }
 
         if (try parser.documentHTMLBody(page.window.document)) |body| {
-            return @alignCast(@ptrCast(body));
+            return @ptrCast(@alignCast(body));
         }
 
         return try parser.documentGetDocumentElement(self);
@@ -287,206 +293,37 @@ pub const Document = struct {
     // we could look for the "disabled" attribute, but that's only meaningful
     // on certain types, and libdom's vtable doesn't seem to expose this.
     pub fn setFocus(self: *parser.Document, e: *parser.ElementHTML, page: *Page) !void {
-        const state = try page.getOrCreateNodeState(@alignCast(@ptrCast(self)));
+        const state = try page.getOrCreateNodeState(@ptrCast(@alignCast(self)));
         state.active_element = @ptrCast(e);
     }
+
+    pub fn _createRange(_: *parser.Document, page: *Page) Range {
+        return Range.constructor(page);
+    }
+
+    // TODO: dummy implementation
+    pub fn get_styleSheets(_: *parser.Document) []CSSStyleSheet {
+        return &.{};
+    }
+
+    pub fn get_adoptedStyleSheets(self: *parser.Document, page: *Page) !Env.JsObject {
+        const state = try page.getOrCreateNodeState(@ptrCast(@alignCast(self)));
+        if (state.adopted_style_sheets) |obj| {
+            return obj;
+        }
+
+        const obj = try page.main_context.newArray(0).persist();
+        state.adopted_style_sheets = obj;
+        return obj;
+    }
+
+    pub fn set_adoptedStyleSheets(self: *parser.Document, sheets: Env.JsObject, page: *Page) !void {
+        const state = try page.getOrCreateNodeState(@ptrCast(@alignCast(self)));
+        state.adopted_style_sheets = try sheets.persist();
+    }
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.Document" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{
-        .url = "about:blank",
-    });
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "document.__proto__.__proto__.constructor.name", "Document" },
-        .{ "document.__proto__.__proto__.__proto__.constructor.name", "Node" },
-        .{ "document.__proto__.__proto__.__proto__.__proto__.constructor.name", "EventTarget" },
-
-        .{ "let newdoc = new Document()", "undefined" },
-        .{ "newdoc.documentElement", "null" },
-        .{ "newdoc.children.length", "0" },
-        .{ "newdoc.getElementsByTagName('*').length", "0" },
-        .{ "newdoc.getElementsByTagName('*').item(0)", "null" },
-        .{ "newdoc.inputEncoding === document.inputEncoding", "true" },
-        .{ "newdoc.documentURI === document.documentURI", "true" },
-        .{ "newdoc.URL === document.URL", "true" },
-        .{ "newdoc.compatMode === document.compatMode", "true" },
-        .{ "newdoc.characterSet === document.characterSet", "true" },
-        .{ "newdoc.charset === document.charset", "true" },
-        .{ "newdoc.contentType === document.contentType", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let getElementById = document.getElementById('content')", "undefined" },
-        .{ "getElementById.constructor.name", "HTMLDivElement" },
-        .{ "getElementById.localName", "div" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let getElementsByTagName = document.getElementsByTagName('p')", "undefined" },
-        .{ "getElementsByTagName.length", "2" },
-        .{ "getElementsByTagName.item(0).localName", "p" },
-        .{ "getElementsByTagName.item(1).localName", "p" },
-        .{ "let getElementsByTagNameAll = document.getElementsByTagName('*')", "undefined" },
-        .{ "getElementsByTagNameAll.length", "8" },
-        .{ "getElementsByTagNameAll.item(0).localName", "html" },
-        .{ "getElementsByTagNameAll.item(7).localName", "p" },
-        .{ "getElementsByTagNameAll.namedItem('para-empty-child').localName", "span" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let ok = document.getElementsByClassName('ok')", "undefined" },
-        .{ "ok.length", "2" },
-        .{ "let empty = document.getElementsByClassName('empty')", "undefined" },
-        .{ "empty.length", "1" },
-        .{ "let emptyok = document.getElementsByClassName('empty ok')", "undefined" },
-        .{ "emptyok.length", "1" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let e = document.documentElement", "undefined" },
-        .{ "e.localName", "html" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.characterSet", "UTF-8" },
-        .{ "document.charset", "UTF-8" },
-        .{ "document.inputEncoding", "UTF-8" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.compatMode", "CSS1Compat" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.contentType", "text/html" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.documentURI", "about:blank" },
-        .{ "document.URL", "about:blank" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let impl = document.implementation", "undefined" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let d = new Document()", "undefined" },
-        .{ "d.characterSet", "UTF-8" },
-        .{ "d.URL", "about:blank" },
-        .{ "d.documentURI", "about:blank" },
-        .{ "d.compatMode", "CSS1Compat" },
-        .{ "d.contentType", "text/html" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "var v = document.createDocumentFragment()", "undefined" },
-        .{ "v.nodeName", "#document-fragment" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "var v = document.createTextNode('foo')", "undefined" },
-        .{ "v.nodeName", "#text" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "var v = document.createCDATASection('foo')", "undefined" },
-        .{ "v.nodeName", "#cdata-section" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "var v = document.createComment('foo')", "undefined" },
-        .{ "v.nodeName", "#comment" },
-        .{ "let v2 = v.cloneNode()", "undefined" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let pi = document.createProcessingInstruction('foo', 'bar')", "undefined" },
-        .{ "pi.target", "foo" },
-        .{ "let pi2 = pi.cloneNode()", "undefined" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let nimp = document.getElementById('content')", "undefined" },
-        .{ "var v = document.importNode(nimp)", "undefined" },
-        .{ "v.nodeName", "DIV" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "var v = document.createAttribute('foo')", "undefined" },
-        .{ "v.nodeName", "foo" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.children.length", "1" },
-        .{ "document.children.item(0).nodeName", "HTML" },
-        .{ "document.firstElementChild.nodeName", "HTML" },
-        .{ "document.lastElementChild.nodeName", "HTML" },
-        .{ "document.childElementCount", "1" },
-
-        .{ "let nd = new Document()", "undefined" },
-        .{ "nd.children.length", "0" },
-        .{ "nd.children.item(0)", "null" },
-        .{ "nd.firstElementChild", "null" },
-        .{ "nd.lastElementChild", "null" },
-        .{ "nd.childElementCount", "0" },
-
-        .{ "let emptydoc = document.createElement('html')", "undefined" },
-        .{ "emptydoc.prepend(document.createElement('html'))", "undefined" },
-
-        .{ "let emptydoc2 = document.createElement('html')", "undefined" },
-        .{ "emptydoc2.append(document.createElement('html'))", "undefined" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.querySelector('')", "null" },
-        .{ "document.querySelector('*').nodeName", "HTML" },
-        .{ "document.querySelector('#content').id", "content" },
-        .{ "document.querySelector('#para').id", "para" },
-        .{ "document.querySelector('.ok').id", "link" },
-        .{ "document.querySelector('a ~ p').id", "para-empty" },
-        .{ "document.querySelector(':root').nodeName", "HTML" },
-
-        .{ "document.querySelectorAll('p').length", "2" },
-        .{
-            \\  Array.from(document.querySelectorAll('#content > p#para-empty'))
-            \\    .map(row => row.querySelector('span').textContent)
-            \\    .length;
-            ,
-            "1",
-        },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.activeElement === document.body", "true" },
-        .{ "document.getElementById('link').focus()", "undefined" },
-        .{ "document.activeElement === document.getElementById('link')", "true" },
-    }, .{});
-
-    // this test breaks the doc structure, keep it at the end of the test
-    // suite.
-    try runner.testCases(&.{
-        .{ "let nadop = document.getElementById('content')", "undefined" },
-        .{ "var v = document.adoptNode(nadop)", "undefined" },
-        .{ "v.nodeName", "DIV" },
-    }, .{});
-
-    const Case = testing.JsRunner.Case;
-    const tags = comptime parser.Tag.all();
-    var createElements: [(tags.len) * 2]Case = undefined;
-    inline for (tags, 0..) |tag, i| {
-        const tag_name = @tagName(tag);
-        createElements[i * 2] = Case{
-            "var " ++ tag_name ++ "Elem = document.createElement('" ++ tag_name ++ "')",
-            "undefined",
-        };
-        createElements[(i * 2) + 1] = Case{
-            tag_name ++ "Elem.localName",
-            tag_name,
-        };
-    }
-    try runner.testCases(&createElements, .{});
+test "Browser: DOM.Document" {
+    try testing.htmlRunner("dom/document.html");
 }

src/browser/dom/document_fragment.zig

@@ -16,8 +16,13 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
+const css = @import("css.zig");
 const parser = @import("../netsurf.zig");
 const Page = @import("../page.zig").Page;
+const NodeList = @import("nodelist.zig").NodeList;
+const Element = @import("element.zig").Element;
+const ElementUnion = @import("element.zig").Union;
+const collection = @import("html_collection.zig");
 
 const Node = @import("node.zig").Node;
 
@@ -53,22 +58,39 @@ pub const DocumentFragment = struct {
     pub fn _replaceChildren(self: *parser.DocumentFragment, nodes: []const Node.NodeOrText) !void {
         return Node.replaceChildren(parser.documentFragmentToNode(self), nodes);
     }
+
+    pub fn _querySelector(self: *parser.DocumentFragment, selector: []const u8, page: *Page) !?ElementUnion {
+        if (selector.len == 0) return null;
+
+        const n = try css.querySelector(page.call_arena, parser.documentFragmentToNode(self), selector);
+
+        if (n == null) return null;
+
+        return try Element.toInterface(parser.nodeToElement(n.?));
+    }
+
+    pub fn _querySelectorAll(self: *parser.DocumentFragment, selector: []const u8, page: *Page) !NodeList {
+        return css.querySelectorAll(page.arena, parser.documentFragmentToNode(self), selector);
+    }
+
+    pub fn get_childElementCount(self: *parser.DocumentFragment) !u32 {
+        var children = try get_children(self);
+        return children.get_length();
+    }
+
+    pub fn get_children(self: *parser.DocumentFragment) !collection.HTMLCollection {
+        return collection.HTMLCollectionChildren(parser.documentFragmentToNode(self), .{
+            .include_root = false,
+        });
+    }
+
+    pub fn _getElementById(self: *parser.DocumentFragment, id: []const u8) !?ElementUnion {
+        const e = try parser.nodeGetElementById(@ptrCast(@alignCast(self)), id) orelse return null;
+        return try Element.toInterface(e);
+    }
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.DocumentFragment" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "const dc = new DocumentFragment()", "undefined" },
-        .{ "dc.constructor.name", "DocumentFragment" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "const dc1 = new DocumentFragment()", "undefined" },
-        .{ "const dc2 = new DocumentFragment()", "undefined" },
-        .{ "dc1.isEqualNode(dc1)", "true" },
-        .{ "dc1.isEqualNode(dc2)", "true" },
-    }, .{});
+test "Browser: DOM.DocumentFragment" {
+    try testing.htmlRunner("dom/document_fragment.html");
 }

src/browser/dom/document_type.zig

@@ -62,19 +62,6 @@ pub const DocumentType = struct {
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.DocumentType" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let dt1 = document.implementation.createDocumentType('qname1', 'pid1', 'sys1');", "undefined" },
-        .{ "let dt2 = document.implementation.createDocumentType('qname2', 'pid2', 'sys2');", "undefined" },
-        .{ "let dt3 = document.implementation.createDocumentType('qname1', 'pid1', 'sys1');", "undefined" },
-        .{ "dt1.isEqualNode(dt1)", "true" },
-        .{ "dt1.isEqualNode(dt3)", "true" },
-        .{ "dt1.isEqualNode(dt2)", "false" },
-        .{ "dt2.isEqualNode(dt3)", "false" },
-        .{ "dt1.isEqualNode(document)", "false" },
-        .{ "document.isEqualNode(dt1)", "false" },
-    }, .{});
+test "Browser: DOM.DocumentType" {
+    try testing.htmlRunner("dom/document_type.html");
 }

src/browser/dom/dom.zig

@@ -23,12 +23,13 @@ const NamedNodeMap = @import("namednodemap.zig").NamedNodeMap;
 const DOMTokenList = @import("token_list.zig");
 const NodeList = @import("nodelist.zig");
 const Node = @import("node.zig");
+const ResizeObserver = @import("resize_observer.zig");
 const MutationObserver = @import("mutation_observer.zig");
 const IntersectionObserver = @import("intersection_observer.zig");
 const DOMParser = @import("dom_parser.zig").DOMParser;
 const TreeWalker = @import("tree_walker.zig").TreeWalker;
+const NodeIterator = @import("node_iterator.zig").NodeIterator;
 const NodeFilter = @import("node_filter.zig").NodeFilter;
-const Performance = @import("performance.zig").Performance;
 const PerformanceObserver = @import("performance_observer.zig").PerformanceObserver;
 
 pub const Interfaces = .{
@@ -41,11 +42,16 @@ pub const Interfaces = .{
     NodeList.Interfaces,
     Node.Node,
     Node.Interfaces,
+    ResizeObserver.Interfaces,
     MutationObserver.Interfaces,
     IntersectionObserver.Interfaces,
     DOMParser,
     TreeWalker,
+    NodeIterator,
     NodeFilter,
-    Performance,
+    @import("performance.zig").Interfaces,
     PerformanceObserver,
+    @import("range.zig").Interfaces,
+    @import("Animation.zig"),
+    @import("MessageChannel.zig").Interfaces,
 };

src/browser/dom/dom_parser.zig

@@ -36,12 +36,6 @@ pub const DOMParser = struct {
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.DOMParser" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "const dp = new DOMParser()", "undefined" },
-        .{ "dp.parseFromString('<div>abc</div>', 'text/html')", "[object HTMLDocument]" },
-    }, .{});
+test "Browser: DOM.Parser" {
+    try testing.htmlRunner("dom/dom_parser.html");
 }

src/browser/dom/element.zig

@@ -30,6 +30,11 @@ const Node = @import("node.zig").Node;
 const Walker = @import("walker.zig").WalkerDepthFirst;
 const NodeList = @import("nodelist.zig").NodeList;
 const HTMLElem = @import("../html/elements.zig");
+const ShadowRoot = @import("../dom/shadow_root.zig").ShadowRoot;
+
+const Animation = @import("Animation.zig");
+const JsObject = @import("../env.zig").JsObject;
+
 pub const Union = @import("../html/elements.zig").Union;
 
 // WEB IDL https://dom.spec.whatwg.org/#element
@@ -50,8 +55,33 @@ pub const Element = struct {
     };
 
     pub fn toInterface(e: *parser.Element) !Union {
-        return try HTMLElem.toInterface(Union, e);
-        // SVGElement and MathML are not supported yet.
+        return toInterfaceT(Union, e);
+    }
+
+    pub fn toInterfaceT(comptime T: type, e: *parser.Element) !T {
+        const tagname = try parser.elementGetTagName(e) orelse {
+            // If the owner's document is HTML, assume we have an HTMLElement.
+            const doc = try parser.nodeOwnerDocument(parser.elementToNode(e));
+            if (doc != null and !doc.?.is_html) {
+                return .{ .HTMLElement = @as(*parser.ElementHTML, @ptrCast(e)) };
+            }
+
+            return .{ .Element = e };
+        };
+
+        // TODO SVGElement and MathML are not supported yet.
+
+        const tag = parser.Tag.fromString(tagname) catch {
+            // If the owner's document is HTML, assume we have an HTMLElement.
+            const doc = try parser.nodeOwnerDocument(parser.elementToNode(e));
+            if (doc != null and doc.?.is_html) {
+                return .{ .HTMLElement = @as(*parser.ElementHTML, @ptrCast(e)) };
+            }
+
+            return .{ .Element = e };
+        };
+
+        return HTMLElem.toInterfaceFromTag(T, e, tag);
     }
 
     // JS funcs
@@ -107,18 +137,18 @@ pub const Element = struct {
     }
 
     pub fn get_innerHTML(self: *parser.Element, page: *Page) ![]const u8 {
-        var buf = std.ArrayList(u8).init(page.arena);
-        try dump.writeChildren(parser.elementToNode(self), buf.writer());
-        return buf.items;
+        var aw = std.Io.Writer.Allocating.init(page.call_arena);
+        try dump.writeChildren(parser.elementToNode(self), .{}, &aw.writer);
+        return aw.written();
     }
 
     pub fn get_outerHTML(self: *parser.Element, page: *Page) ![]const u8 {
-        var buf = std.ArrayList(u8).init(page.arena);
-        try dump.writeNode(parser.elementToNode(self), buf.writer());
-        return buf.items;
+        var aw = std.Io.Writer.Allocating.init(page.call_arena);
+        try dump.writeNode(parser.elementToNode(self), .{}, &aw.writer);
+        return aw.written();
     }
 
-    pub fn set_innerHTML(self: *parser.Element, str: []const u8) !void {
+    pub fn set_innerHTML(self: *parser.Element, str: []const u8, page: *Page) !void {
         const node = parser.elementToNode(self);
         const doc = try parser.nodeOwnerDocument(node) orelse return parser.DOMError.WrongDocument;
         // parse the fragment
@@ -127,16 +157,64 @@ pub const Element = struct {
         // remove existing children
         try Node.removeChildren(node);
 
-        // get fragment body children
-        const children = try parser.documentFragmentBodyChildren(fragment) orelse return;
+        const fragment_node = parser.documentFragmentToNode(fragment);
 
-        // append children to the node
-        const ln = try parser.nodeListLength(children);
-        for (0..ln) |_| {
-            // always index 0, because ndoeAppendChild moves the node out of
-            // the nodeList and into the new tree
-            const child = try parser.nodeListItem(children, 0) orelse continue;
-            _ = try parser.nodeAppendChild(node, child);
+        // I'm not sure what the exact behavior is supposed to be. Initially,
+        // we were only copying the body of the document fragment. But it seems
+        // like head elements should be copied too. Specifically, some sites
+        // create script tags via innerHTML, which we need to capture.
+        // If you play with this in a browser, you should notice that the
+        // behavior is different depending on whether you're in a blank page
+        // or an actual document. In a blank page, something like:
+        //    x.innerHTML = '<script></script>';
+        // does _not_ create an empty script, but in a real page, it does. Weird.
+        const html = try parser.nodeFirstChild(fragment_node) orelse return;
+        const head = try parser.nodeFirstChild(html) orelse return;
+        const body = try parser.nodeNextSibling(head) orelse return;
+
+        if (try parser.elementTag(self) == .template) {
+            // HTMLElementTemplate is special. We don't append these as children
+            // of the template, but instead set its content as the body of the
+            // fragment. Simpler to do this by copying the body children into
+            // a new fragment
+            const clean = try parser.documentCreateDocumentFragment(doc);
+            const children = try parser.nodeGetChildNodes(body);
+            const ln = try parser.nodeListLength(children);
+            for (0..ln) |_| {
+                // always index 0, because nodeAppendChild moves the node out of
+                // the nodeList and into the new tree
+                const child = try parser.nodeListItem(children, 0) orelse continue;
+                _ = try parser.nodeAppendChild(@ptrCast(@alignCast(clean)), child);
+            }
+
+            const state = try page.getOrCreateNodeState(node);
+            state.template_content = clean;
+            return;
+        }
+
+        // For any node other than a template, we copy the head and body elements
+        // as child nodes of the element
+        {
+            // First, copy some of the head element
+            const children = try parser.nodeGetChildNodes(head);
+            const ln = try parser.nodeListLength(children);
+            for (0..ln) |_| {
+                // always index 0, because nodeAppendChild moves the node out of
+                // the nodeList and into the new tree
+                const child = try parser.nodeListItem(children, 0) orelse continue;
+                _ = try parser.nodeAppendChild(node, child);
+            }
+        }
+
+        {
+            const children = try parser.nodeGetChildNodes(body);
+            const ln = try parser.nodeListLength(children);
+            for (0..ln) |_| {
+                // always index 0, because nodeAppendChild moves the node out of
+                // the nodeList and into the new tree
+                const child = try parser.nodeListItem(children, 0) orelse continue;
+                _ = try parser.nodeAppendChild(node, child);
+            }
         }
     }
 
@@ -160,8 +238,14 @@ pub const Element = struct {
         }
     }
 
+    // don't use parser.nodeHasAttributes(...) because that returns true/false
+    // based on the type, e.g. a node never as attributes, an element always has
+    // attributes. But, Element.hasAttributes is supposed to return true only
+    // if the element has at least 1 attribute.
     pub fn _hasAttributes(self: *parser.Element) !bool {
-        return try parser.nodeHasAttributes(parser.elementToNode(self));
+        // an element _must_ have at least an empty attribute
+        const node_map = try parser.nodeGetAttributes(parser.elementToNode(self)) orelse unreachable;
+        return try parser.namedNodeMapGetLength(node_map) > 0;
     }
 
     pub fn _getAttribute(self: *parser.Element, qname: []const u8) !?[]const u8 {
@@ -230,6 +314,22 @@ pub const Element = struct {
         return true;
     }
 
+    pub fn _getAttributeNames(self: *parser.Element, page: *Page) ![]const []const u8 {
+        const attributes = try parser.nodeGetAttributes(@ptrCast(self)) orelse return &.{};
+        const ln = try parser.namedNodeMapGetLength(attributes);
+
+        const names = try page.call_arena.alloc([]const u8, ln);
+        var at: usize = 0;
+
+        for (0..ln) |i| {
+            const attribute = try parser.namedNodeMapItem(attributes, @intCast(i)) orelse break;
+            names[at] = try parser.attributeGetName(attribute);
+            at += 1;
+        }
+
+        return names[0..at];
+    }
+
     pub fn _getAttributeNode(self: *parser.Element, name: []const u8) !?*parser.Attribute {
         return try parser.elementGetAttributeNode(self, name);
     }
@@ -259,7 +359,7 @@ pub const Element = struct {
             page.arena,
             parser.elementToNode(self),
             tag_name,
-            false,
+            .{ .include_root = false },
         );
     }
 
@@ -272,14 +372,16 @@ pub const Element = struct {
             page.arena,
             parser.elementToNode(self),
             classNames,
-            false,
+            .{ .include_root = false },
         );
     }
 
     // ParentNode
     // https://dom.spec.whatwg.org/#parentnode
     pub fn get_children(self: *parser.Element) !collection.HTMLCollection {
-        return try collection.HTMLCollectionChildren(parser.elementToNode(self), false);
+        return collection.HTMLCollectionChildren(parser.elementToNode(self), .{
+            .include_root = false,
+        });
     }
 
     pub fn get_firstElementChild(self: *parser.Element) !?Union {
@@ -307,13 +409,13 @@ pub const Element = struct {
     pub fn get_previousElementSibling(self: *parser.Element) !?Union {
         const res = try parser.nodePreviousElementSibling(parser.elementToNode(self));
         if (res == null) return null;
-        return try HTMLElem.toInterface(HTMLElem.Union, res.?);
+        return try toInterface(res.?);
     }
 
     pub fn get_nextElementSibling(self: *parser.Element) !?Union {
         const res = try parser.nodeNextElementSibling(parser.elementToNode(self));
         if (res == null) return null;
-        return try HTMLElem.toInterface(HTMLElem.Union, res.?);
+        return try toInterface(res.?);
     }
 
     fn getElementById(self: *parser.Element, id: []const u8) !?*parser.Node {
@@ -335,7 +437,7 @@ pub const Element = struct {
     pub fn _querySelector(self: *parser.Element, selector: []const u8, page: *Page) !?Union {
         if (selector.len == 0) return null;
 
-        const n = try css.querySelector(page.arena, parser.elementToNode(self), selector);
+        const n = try css.querySelector(page.call_arena, parser.elementToNode(self), selector);
 
         if (n == null) return null;
 
@@ -429,254 +531,79 @@ pub const Element = struct {
         _ = opts;
         return true;
     }
+
+    const AttachShadowOpts = struct {
+        mode: []const u8, // must be specified
+    };
+    pub fn _attachShadow(self: *parser.Element, opts: AttachShadowOpts, page: *Page) !*ShadowRoot {
+        const mode = std.meta.stringToEnum(ShadowRoot.Mode, opts.mode) orelse return error.InvalidArgument;
+        const state = try page.getOrCreateNodeState(@ptrCast(@alignCast(self)));
+        if (state.shadow_root) |sr| {
+            if (mode != sr.mode) {
+                // this is the behavior per the spec
+                return error.NotSupportedError;
+            }
+
+            try Node.removeChildren(@ptrCast(@alignCast(sr.proto)));
+            return sr;
+        }
+
+        // Not sure what to do if there is no owner document
+        const doc = try parser.nodeOwnerDocument(@ptrCast(self)) orelse return error.InvalidArgument;
+        const fragment = try parser.documentCreateDocumentFragment(doc);
+        const sr = try page.arena.create(ShadowRoot);
+        sr.* = .{
+            .host = self,
+            .mode = mode,
+            .proto = fragment,
+        };
+        state.shadow_root = sr;
+        parser.documentFragmentSetHost(sr.proto, @ptrCast(@alignCast(self)));
+
+        // Storing the ShadowRoot on the element makes sense, it's the ShadowRoot's
+        // parent. When we render, we go top-down, so we'll have the element, get
+        // its shadowroot, and go on. that's what the above code does.
+        // But we sometimes need to go bottom-up, e.g when we have a slot element
+        // and want to find the containing parent. Unforatunately , we don't have
+        // that link, so we need to create it. In the DOM, the ShadowRoot is
+        // represented by this DocumentFragment (it's the ShadowRoot's base prototype)
+        // So we can also store the ShadowRoot in the DocumentFragment's state.
+        const fragment_state = try page.getOrCreateNodeState(@ptrCast(@alignCast(fragment)));
+        fragment_state.shadow_root = sr;
+
+        return sr;
+    }
+
+    pub fn get_shadowRoot(self: *parser.Element, page: *Page) ?*ShadowRoot {
+        const state = page.getNodeState(@ptrCast(@alignCast(self))) orelse return null;
+        const sr = state.shadow_root orelse return null;
+        if (sr.mode == .closed) {
+            return null;
+        }
+        return sr;
+    }
+
+    pub fn _animate(self: *parser.Element, effect: JsObject, opts: JsObject) !Animation {
+        _ = self;
+        _ = opts;
+        return Animation.constructor(effect, null);
+    }
+
+    pub fn _remove(self: *parser.Element) !void {
+        // TODO: This hasn't been tested to make sure all references to this
+        // node are properly updated. A lot of libdom is lazy and will look
+        // for related elements JIT by walking the tree, but there could be
+        // cases in libdom or the Zig WebAPI where this reference is kept
+        const as_node: *parser.Node = @ptrCast(self);
+        const parent = try parser.nodeParentNode(as_node) orelse return;
+        _ = try Node._removeChild(parent, as_node);
+    }
 };
 
 // Tests
 // -----
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.Element" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let g = document.getElementById('content')", "undefined" },
-        .{ "g.namespaceURI", "http://www.w3.org/1999/xhtml" },
-        .{ "g.prefix", "null" },
-        .{ "g.localName", "div" },
-        .{ "g.tagName", "DIV" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let gs = document.getElementById('content')", "undefined" },
-        .{ "gs.id", "content" },
-        .{ "gs.id = 'foo'", "foo" },
-        .{ "gs.id", "foo" },
-        .{ "gs.id = 'content'", "content" },
-        .{ "gs.className", "" },
-        .{ "let gs2 = document.getElementById('para-empty')", "undefined" },
-        .{ "gs2.className", "ok empty" },
-        .{ "gs2.className = 'foo bar baz'", "foo bar baz" },
-        .{ "gs2.className", "foo bar baz" },
-        .{ "gs2.className = 'ok empty'", "ok empty" },
-        .{ "let cl = gs2.classList", "undefined" },
-        .{ "cl.length", "2" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "const el2 = document.createElement('div');", "undefined" },
-        .{ "el2.id = 'closest'; el2.className = 'ok';", "ok" },
-        .{ "el2.closest('#closest')", "[object HTMLDivElement]" },
-        .{ "el2.closest('.ok')", "[object HTMLDivElement]" },
-        .{ "el2.closest('#9000')", "null" },
-        .{ "el2.closest('.notok')", "null" },
-
-        .{ "const sp = document.createElement('span');", "undefined" },
-        .{ "el2.appendChild(sp);", "[object HTMLSpanElement]" },
-        .{ "sp.closest('#closest')", "[object HTMLDivElement]" },
-        .{ "sp.closest('#9000')", "null" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let a = document.getElementById('content')", "undefined" },
-        .{ "a.hasAttributes()", "true" },
-        .{ "a.attributes.length", "1" },
-        .{ "a.getAttribute('id')", "content" },
-        .{ "a.attributes['id'].value", "content" },
-        .{
-            \\ let x = '';
-            \\ for (const attr of a.attributes) {
-            \\   x += attr.name + '=' + attr.value;
-            \\ }
-            \\ x;
-            ,
-            "id=content",
-        },
-
-        .{ "a.hasAttribute('foo')", "false" },
-        .{ "a.getAttribute('foo')", "null" },
-
-        .{ "a.setAttribute('foo', 'bar')", "undefined" },
-        .{ "a.hasAttribute('foo')", "true" },
-        .{ "a.getAttribute('foo')", "bar" },
-
-        .{ "a.setAttribute('foo', 'baz')", "undefined" },
-        .{ "a.hasAttribute('foo')", "true" },
-        .{ "a.getAttribute('foo')", "baz" },
-
-        .{ "a.removeAttribute('foo')", "undefined" },
-        .{ "a.hasAttribute('foo')", "false" },
-        .{ "a.getAttribute('foo')", "null" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let b = document.getElementById('content')", "undefined" },
-        .{ "b.toggleAttribute('foo')", "true" },
-        .{ "b.hasAttribute('foo')", "true" },
-        .{ "b.getAttribute('foo')", "" },
-
-        .{ "b.toggleAttribute('foo')", "false" },
-        .{ "b.hasAttribute('foo')", "false" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let c = document.getElementById('content')", "undefined" },
-        .{ "c.children.length", "3" },
-        .{ "c.firstElementChild.nodeName", "A" },
-        .{ "c.lastElementChild.nodeName", "P" },
-        .{ "c.childElementCount", "3" },
-
-        .{ "c.prepend(document.createTextNode('foo'))", "undefined" },
-        .{ "c.append(document.createTextNode('bar'))", "undefined" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let d = document.getElementById('para')", "undefined" },
-        .{ "d.previousElementSibling.nodeName", "P" },
-        .{ "d.nextElementSibling", "null" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let e = document.getElementById('content')", "undefined" },
-        .{ "e.querySelector('foo')", "null" },
-        .{ "e.querySelector('#foo')", "null" },
-        .{ "e.querySelector('#link').id", "link" },
-        .{ "e.querySelector('#para').id", "para" },
-        .{ "e.querySelector('*').id", "link" },
-        .{ "e.querySelector('')", "null" },
-        .{ "e.querySelector('*').id", "link" },
-        .{ "e.querySelector('#content')", "null" },
-        .{ "e.querySelector('#para').id", "para" },
-        .{ "e.querySelector('.ok').id", "link" },
-        .{ "e.querySelector('a ~ p').id", "para-empty" },
-
-        .{ "e.querySelectorAll('foo').length", "0" },
-        .{ "e.querySelectorAll('#foo').length", "0" },
-        .{ "e.querySelectorAll('#link').length", "1" },
-        .{ "e.querySelectorAll('#link').item(0).id", "link" },
-        .{ "e.querySelectorAll('#para').length", "1" },
-        .{ "e.querySelectorAll('#para').item(0).id", "para" },
-        .{ "e.querySelectorAll('*').length", "4" },
-        .{ "e.querySelectorAll('p').length", "2" },
-        .{ "e.querySelectorAll('.ok').item(0).id", "link" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let f = document.getElementById('content')", "undefined" },
-        .{ "let ff = document.createAttribute('foo')", "undefined" },
-        .{ "f.setAttributeNode(ff)", "null" },
-        .{ "f.getAttributeNode('foo').name", "foo" },
-        .{ "f.removeAttributeNode(ff).name", "foo" },
-        .{ "f.getAttributeNode('bar')", "null" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.getElementById('para').innerHTML", " And" },
-        .{ "document.getElementById('para-empty').innerHTML.trim()", "<span id=\"para-empty-child\"></span>" },
-
-        .{ "let h = document.getElementById('para-empty')", "undefined" },
-        .{ "const prev = h.innerHTML", "undefined" },
-        .{ "h.innerHTML = '<p id=\"hello\">hello world</p>'", "<p id=\"hello\">hello world</p>" },
-        .{ "h.innerHTML", "<p id=\"hello\">hello world</p>" },
-        .{ "h.firstChild.nodeName", "P" },
-        .{ "h.firstChild.id", "hello" },
-        .{ "h.firstChild.textContent", "hello world" },
-        .{ "h.innerHTML = prev; true", "true" },
-        .{ "document.getElementById('para-empty').innerHTML.trim()", "<span id=\"para-empty-child\"></span>" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.getElementById('para').outerHTML", "<p id=\"para\"> And</p>" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "document.getElementById('para').clientWidth", "1" },
-        .{ "document.getElementById('para').clientHeight", "1" },
-
-        .{ "let r1 = document.getElementById('para').getBoundingClientRect()", "undefined" },
-        .{ "r1.x", "0" },
-        .{ "r1.y", "0" },
-        .{ "r1.width", "1" },
-        .{ "r1.height", "1" },
-
-        .{ "let r2 = document.getElementById('content').getBoundingClientRect()", "undefined" },
-        .{ "r2.x", "1" },
-        .{ "r2.y", "0" },
-        .{ "r2.width", "1" },
-        .{ "r2.height", "1" },
-
-        .{ "let r3 = document.getElementById('para').getBoundingClientRect()", "undefined" },
-        .{ "r3.x", "0" },
-        .{ "r3.y", "0" },
-        .{ "r3.width", "1" },
-        .{ "r3.height", "1" },
-
-        .{ "document.getElementById('para').clientWidth", "2" },
-        .{ "document.getElementById('para').clientHeight", "1" },
-
-        .{ "let r4 = document.createElement('div').getBoundingClientRect()", null },
-        .{ "r4.x", "0" },
-        .{ "r4.y", "0" },
-        .{ "r4.width", "0" },
-        .{ "r4.height", "0" },
-
-        // Test setup causes WrongDocument or HierarchyRequest error unlike in chrome/firefox
-        // .{ // An element of another document, even if created from the main document, is not rendered.
-        //     \\ let div5 = document.createElement('div');
-        //     \\ const newDoc = document.implementation.createHTMLDocument("New Document");
-        //     \\ newDoc.body.appendChild(div5);
-        //     \\ let r5 = div5.getBoundingClientRect();
-        //     ,
-        //     null,
-        // },
-        // .{ "r5.x", "0" },
-        // .{ "r5.y", "0" },
-        // .{ "r5.width", "0" },
-        // .{ "r5.height", "0" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "const el = document.createElement('div');", "undefined" },
-        .{ "el.id = 'matches'; el.className = 'ok';", "ok" },
-        .{ "el.matches('#matches')", "true" },
-        .{ "el.matches('.ok')", "true" },
-        .{ "el.matches('#9000')", "false" },
-        .{ "el.matches('.notok')", "false" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "const el3 = document.createElement('div');", "undefined" },
-        .{ "el3.scrollIntoViewIfNeeded();", "undefined" },
-        .{ "el3.scrollIntoViewIfNeeded(false);", "undefined" },
-    }, .{});
-
-    // before
-    try runner.testCases(&.{
-        .{ "const before_container = document.createElement('div');", "undefined" },
-        .{ "document.append(before_container);", "undefined" },
-        .{ "const b1 = document.createElement('div');", "undefined" },
-        .{ "before_container.append(b1);", "undefined" },
-
-        .{ "const b1_a = document.createElement('p');", "undefined" },
-        .{ "b1.before(b1_a, 'over 9000');", "undefined" },
-        .{ "before_container.innerHTML", "<p></p>over 9000<div></div>" },
-    }, .{});
-
-    // after
-    try runner.testCases(&.{
-        .{ "const after_container = document.createElement('div');", "undefined" },
-        .{ "document.append(after_container);", "undefined" },
-        .{ "const a1 = document.createElement('div');", "undefined" },
-        .{ "after_container.append(a1);", "undefined" },
-
-        .{ "const a1_a = document.createElement('p');", "undefined" },
-        .{ "a1.after('over 9000', a1_a);", "undefined" },
-        .{ "after_container.innerHTML", "<div></div>over 9000<p></p>" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "var div1 = document.createElement('div');", null },
-        .{ "div1.innerHTML = \"  <link/><table></table><a href='/a'>a</a><input type='checkbox'/>\"", null },
-        .{ "div1.getElementsByTagName('a').length", "1" },
-    }, .{});
+test "Browser: DOM.Element" {
+    try testing.htmlRunner("dom/element.html");
 }

src/browser/dom/event_target.zig

@@ -16,6 +16,7 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
+const std = @import("std");
 const Env = @import("../env.zig").Env;
 const parser = @import("../netsurf.zig");
 const Page = @import("../page.zig").Page;
@@ -23,30 +24,75 @@ const Page = @import("../page.zig").Page;
 const EventHandler = @import("../events/event.zig").EventHandler;
 
 const DOMException = @import("exceptions.zig").DOMException;
-const Nod = @import("node.zig");
+const nod = @import("node.zig");
 
-// EventTarget interfaces
-pub const Union = Nod.Union;
+pub const Union = union(enum) {
+    node: nod.Union,
+    xhr: *@import("../xhr/xhr.zig").XMLHttpRequest,
+    plain: *parser.EventTarget,
+    message_port: *@import("MessageChannel.zig").MessagePort,
+    screen: *@import("../html/screen.zig").Screen,
+    screen_orientation: *@import("../html/screen.zig").ScreenOrientation,
+    performance: *@import("performance.zig").Performance,
+    media_query_list: *@import("../html/media_query_list.zig").MediaQueryList,
+};
 
 // EventTarget implementation
 pub const EventTarget = struct {
     pub const Self = parser.EventTarget;
     pub const Exception = DOMException;
 
+    // Extend libdom event target for pure zig struct.
+    base: parser.EventTargetTBase = parser.EventTargetTBase{ .internal_target_type = .plain },
+
     pub fn toInterface(et: *parser.EventTarget, page: *Page) !Union {
-        // Not all targets are *parser.Nodes. page.zig emits a "load" event
-        // where the target is a Window, which cannot be cast directly to a node.
-        // Ideally, we'd remove this duality. Failing that, we'll need to embed
-        // data into the *parser.EventTarget should we need this for other types.
-        // For now, for the Window, which is a singleton, we can do this:
-        if (@intFromPtr(et) == @intFromPtr(&page.window.base)) {
-            return .{ .Window = &page.window };
+        // libdom assumes that all event targets are libdom nodes. They are not.
+
+        switch (try parser.eventTargetInternalType(et)) {
+            .libdom_node => {
+                return .{ .node = try nod.Node.toInterface(@as(*parser.Node, @ptrCast(et))) };
+            },
+            .plain => return .{ .plain = et },
+            .abort_signal => {
+                // AbortSignal is a special case, it has its own internal type.
+                // We return it as a node, but we need to handle it differently.
+                return .{ .node = .{ .AbortSignal = @fieldParentPtr("proto", @as(*parser.EventTargetTBase, @ptrCast(et))) } };
+            },
+            .window => {
+                // The window is a common non-node target, but it's easy to handle as its a singleton.
+                std.debug.assert(@intFromPtr(et) == @intFromPtr(&page.window.base));
+                return .{ .node = .{ .Window = &page.window } };
+            },
+            .xhr => {
+                const XMLHttpRequestEventTarget = @import("../xhr/event_target.zig").XMLHttpRequestEventTarget;
+                const base: *XMLHttpRequestEventTarget = @fieldParentPtr("base", @as(*parser.EventTargetTBase, @ptrCast(et)));
+                return .{ .xhr = @fieldParentPtr("proto", base) };
+            },
+            .message_port => {
+                return .{ .message_port = @fieldParentPtr("proto", @as(*parser.EventTargetTBase, @ptrCast(et))) };
+            },
+            .screen => {
+                return .{ .screen = @fieldParentPtr("proto", @as(*parser.EventTargetTBase, @ptrCast(et))) };
+            },
+            .screen_orientation => {
+                return .{ .screen_orientation = @fieldParentPtr("proto", @as(*parser.EventTargetTBase, @ptrCast(et))) };
+            },
+            .performance => {
+                return .{ .performance = @fieldParentPtr("base", @as(*parser.EventTargetTBase, @ptrCast(et))) };
+            },
+            .media_query_list => {
+                return .{ .media_query_list = @fieldParentPtr("base", @as(*parser.EventTargetTBase, @ptrCast(et))) };
+            },
         }
-        return Nod.Node.toInterface(@as(*parser.Node, @ptrCast(et)));
     }
 
     // JS funcs
     // --------
+    pub fn constructor(page: *Page) !*parser.EventTarget {
+        const et = try page.arena.create(EventTarget);
+        return @ptrCast(&et.base);
+    }
+
     pub fn _addEventListener(
         self: *parser.EventTarget,
         typ: []const u8,
@@ -108,130 +154,6 @@ pub const EventTarget = struct {
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.EventTarget" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let content = document.getElementById('content')", "undefined" },
-        .{ "let para = document.getElementById('para')", "undefined" },
-        // NOTE: as some event properties will change during the event dispatching phases
-        // we need to copy thoses values in order to check them afterwards
-        .{
-            \\ var nb = 0; var evt; var phase; var cur;
-            \\ function cbk(event) {
-            \\   evt = event;
-            \\   phase = event.eventPhase;
-            \\   cur = event.currentTarget;
-            \\   nb ++;
-            \\ }
-            ,
-            "undefined",
-        },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "content.addEventListener('basic', cbk)", "undefined" },
-        .{ "content.dispatchEvent(new Event('basic'))", "true" },
-        .{ "nb", "1" },
-        .{ "evt instanceof Event", "true" },
-        .{ "evt.type", "basic" },
-        .{ "phase", "2" },
-        .{ "cur.getAttribute('id')", "content" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb = 0; evt = undefined; phase = undefined; cur = undefined", "undefined" },
-        .{ "para.dispatchEvent(new Event('basic'))", "true" },
-        .{ "nb", "0" }, // handler is not called, no capture, not the target, no bubbling
-        .{ "evt === undefined", "true" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb  = 0", "0" },
-        .{ "content.addEventListener('basic', cbk)", "undefined" },
-        .{ "content.dispatchEvent(new Event('basic'))", "true" },
-        .{ "nb", "1" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb  = 0", "0" },
-        .{ "content.addEventListener('basic', cbk, true)", "undefined" },
-        .{ "content.dispatchEvent(new Event('basic'))", "true" },
-        .{ "nb", "2" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb  = 0", "0" },
-        .{ "content.removeEventListener('basic', cbk)", "undefined" },
-        .{ "content.dispatchEvent(new Event('basic'))", "true" },
-        .{ "nb", "1" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb  = 0", "0" },
-        .{ "content.removeEventListener('basic', cbk, {capture: true})", "undefined" },
-        .{ "content.dispatchEvent(new Event('basic'))", "true" },
-        .{ "nb", "0" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb = 0; evt = undefined; phase = undefined; cur = undefined", "undefined" },
-        .{ "content.addEventListener('capture', cbk, true)", "undefined" },
-        .{ "content.dispatchEvent(new Event('capture'))", "true" },
-        .{ "nb", "1" },
-        .{ "evt instanceof Event", "true" },
-        .{ "evt.type", "capture" },
-        .{ "phase", "2" },
-        .{ "cur.getAttribute('id')", "content" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb = 0; evt = undefined; phase = undefined; cur = undefined", "undefined" },
-        .{ "para.dispatchEvent(new Event('capture'))", "true" },
-        .{ "nb", "1" },
-        .{ "evt instanceof Event", "true" },
-        .{ "evt.type", "capture" },
-        .{ "phase", "1" },
-        .{ "cur.getAttribute('id')", "content" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb = 0; evt = undefined; phase = undefined; cur = undefined", "undefined" },
-        .{ "content.addEventListener('bubbles', cbk)", "undefined" },
-        .{ "content.dispatchEvent(new Event('bubbles', {bubbles: true}))", "true" },
-        .{ "nb", "1" },
-        .{ "evt instanceof Event", "true" },
-        .{ "evt.type", "bubbles" },
-        .{ "evt.bubbles", "true" },
-        .{ "phase", "2" },
-        .{ "cur.getAttribute('id')", "content" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb = 0; evt = undefined; phase = undefined; cur = undefined", "undefined" },
-        .{ "para.dispatchEvent(new Event('bubbles', {bubbles: true}))", "true" },
-        .{ "nb", "1" },
-        .{ "evt instanceof Event", "true" },
-        .{ "evt.type", "bubbles" },
-        .{ "phase", "3" },
-        .{ "cur.getAttribute('id')", "content" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "const obj1 = {calls: 0, handleEvent: function() { this.calls += 1; } };", null },
-        .{ "content.addEventListener('he', obj1);", null },
-        .{ "content.dispatchEvent(new Event('he'));", null },
-        .{ "obj1.calls", "1" },
-
-        .{ "content.removeEventListener('he', obj1);", null },
-        .{ "content.dispatchEvent(new Event('he'));", null },
-        .{ "obj1.calls", "1" },
-    }, .{});
-
-    // doesn't crash on null receiver
-    try runner.testCases(&.{
-        .{ "content.addEventListener('he2', null);", null },
-        .{ "content.dispatchEvent(new Event('he2'));", null },
-    }, .{});
+test "Browser: DOM.EventTarget" {
+    try testing.htmlRunner("dom/event_target.html");
 }

src/browser/dom/exceptions.zig

@@ -20,10 +20,11 @@ const std = @import("std");
 const allocPrint = std.fmt.allocPrint;
 
 const parser = @import("../netsurf.zig");
+const Page = @import("../page.zig").Page;
 
 // https://webidl.spec.whatwg.org/#idl-DOMException
 pub const DOMException = struct {
-    err: parser.DOMError,
+    err: ?parser.DOMError,
     str: []const u8,
 
     pub const ErrorSet = parser.DOMError;
@@ -55,34 +56,84 @@ pub const DOMException = struct {
     pub const _INVALID_NODE_TYPE_ERR = 24;
     pub const _DATA_CLONE_ERR = 25;
 
+    pub fn constructor(message_: ?[]const u8, name_: ?[]const u8, page: *const Page) !DOMException {
+        const message = message_ orelse "";
+        const err = if (name_) |n| error_from_str(n) else null;
+        const fixed_name = name(err);
+
+        if (message.len == 0) return .{ .err = err, .str = fixed_name };
+
+        const str = try allocPrint(page.arena, "{s}: {s}", .{ fixed_name, message });
+        return .{ .err = err, .str = str };
+    }
+
     // TODO: deinit
-    pub fn init(alloc: std.mem.Allocator, err: anyerror, callerName: []const u8) !DOMException {
-        const errCast = @as(parser.DOMError, @errorCast(err));
-        const errName = DOMException.name(errCast);
-        const str = switch (errCast) {
+    pub fn init(alloc: std.mem.Allocator, err: anyerror, caller_name: []const u8) !DOMException {
+        const dom_error = @as(parser.DOMError, @errorCast(err));
+        const error_name = DOMException.name(dom_error);
+        const str = switch (dom_error) {
             error.HierarchyRequest => try allocPrint(
                 alloc,
                 "{s}: Failed to execute '{s}' on 'Node': The new child element contains the parent.",
-                .{ errName, callerName },
+                .{ error_name, caller_name },
             ),
-            error.NoError => unreachable,
+            // todo add more custom error messages
             else => try allocPrint(
                 alloc,
-                "{s}: TODO message", // TODO: implement other messages
-                .{DOMException.name(errCast)},
+                "{s}: Failed to execute '{s}' : {s}",
+                .{ error_name, caller_name, error_name },
             ),
+            error.NoError => unreachable,
         };
-        return .{ .err = errCast, .str = str };
+        return .{ .err = dom_error, .str = str };
     }
 
-    fn name(err: parser.DOMError) []const u8 {
+    fn error_from_str(name_: []const u8) ?parser.DOMError {
+        // @speed: Consider length first, left as is for maintainability, awaiting switch on string support
+        if (std.mem.eql(u8, name_, "IndexSizeError")) return error.IndexSize;
+        if (std.mem.eql(u8, name_, "StringSizeError")) return error.StringSize;
+        if (std.mem.eql(u8, name_, "HierarchyRequestError")) return error.HierarchyRequest;
+        if (std.mem.eql(u8, name_, "WrongDocumentError")) return error.WrongDocument;
+        if (std.mem.eql(u8, name_, "InvalidCharacterError")) return error.InvalidCharacter;
+        if (std.mem.eql(u8, name_, "NoDataAllowedError")) return error.NoDataAllowed;
+        if (std.mem.eql(u8, name_, "NoModificationAllowedError")) return error.NoModificationAllowed;
+        if (std.mem.eql(u8, name_, "NotFoundError")) return error.NotFound;
+        if (std.mem.eql(u8, name_, "NotSupportedError")) return error.NotSupported;
+        if (std.mem.eql(u8, name_, "InuseAttributeError")) return error.InuseAttribute;
+        if (std.mem.eql(u8, name_, "InvalidStateError")) return error.InvalidState;
+        if (std.mem.eql(u8, name_, "SyntaxError")) return error.Syntax;
+        if (std.mem.eql(u8, name_, "InvalidModificationError")) return error.InvalidModification;
+        if (std.mem.eql(u8, name_, "NamespaceError")) return error.Namespace;
+        if (std.mem.eql(u8, name_, "InvalidAccessError")) return error.InvalidAccess;
+        if (std.mem.eql(u8, name_, "ValidationError")) return error.Validation;
+        if (std.mem.eql(u8, name_, "TypeMismatchError")) return error.TypeMismatch;
+        if (std.mem.eql(u8, name_, "SecurityError")) return error.Security;
+        if (std.mem.eql(u8, name_, "NetworkError")) return error.Network;
+        if (std.mem.eql(u8, name_, "AbortError")) return error.Abort;
+        if (std.mem.eql(u8, name_, "URLismatchError")) return error.URLismatch;
+        if (std.mem.eql(u8, name_, "QuotaExceededError")) return error.QuotaExceeded;
+        if (std.mem.eql(u8, name_, "TimeoutError")) return error.Timeout;
+        if (std.mem.eql(u8, name_, "InvalidNodeTypeError")) return error.InvalidNodeType;
+        if (std.mem.eql(u8, name_, "DataCloneError")) return error.DataClone;
+
+        // custom netsurf error
+        if (std.mem.eql(u8, name_, "UnspecifiedEventTypeError")) return error.UnspecifiedEventType;
+        if (std.mem.eql(u8, name_, "DispatchRequestError")) return error.DispatchRequest;
+        if (std.mem.eql(u8, name_, "NoMemoryError")) return error.NoMemory;
+        if (std.mem.eql(u8, name_, "AttributeWrongTypeError")) return error.AttributeWrongType;
+        return null;
+    }
+
+    fn name(err_: ?parser.DOMError) []const u8 {
+        const err = err_ orelse return "Error";
+
         return switch (err) {
             error.IndexSize => "IndexSizeError",
-            error.StringSize => "StringSizeError",
+            error.StringSize => "StringSizeError", // Legacy: DOMSTRING_SIZE_ERR
             error.HierarchyRequest => "HierarchyRequestError",
             error.WrongDocument => "WrongDocumentError",
             error.InvalidCharacter => "InvalidCharacterError",
-            error.NoDataAllowed => "NoDataAllowedError",
+            error.NoDataAllowed => "NoDataAllowedError", // Legacy: NO_DATA_ALLOWED_ERR
             error.NoModificationAllowed => "NoModificationAllowedError",
             error.NotFound => "NotFoundError",
             error.NotSupported => "NotSupportedError",
@@ -92,7 +143,7 @@ pub const DOMException = struct {
             error.InvalidModification => "InvalidModificationError",
             error.Namespace => "NamespaceError",
             error.InvalidAccess => "InvalidAccessError",
-            error.Validation => "ValidationError",
+            error.Validation => "ValidationError", // Legacy: VALIDATION_ERR
             error.TypeMismatch => "TypeMismatchError",
             error.Security => "SecurityError",
             error.Network => "NetworkError",
@@ -115,7 +166,8 @@ pub const DOMException = struct {
     // JS properties and methods
 
     pub fn get_code(self: *const DOMException) u8 {
-        return switch (self.err) {
+        const err = self.err orelse return 0;
+        return switch (err) {
             error.IndexSize => 1,
             error.StringSize => 2,
             error.HierarchyRequest => 3,
@@ -157,7 +209,8 @@ pub const DOMException = struct {
 
     pub fn get_message(self: *const DOMException) []const u8 {
         const errName = DOMException.name(self.err);
-        return self.str[errName.len + 2 ..];
+        if (self.str.len <= errName.len + 2) return "";
+        return self.str[errName.len + 2 ..]; // ! Requires str is formatted as "{name}: {message}"
     }
 
     pub fn _toString(self: *const DOMException) []const u8 {
@@ -166,26 +219,6 @@ pub const DOMException = struct {
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.Exception" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    const err = "Failed to execute 'appendChild' on 'Node': The new child element contains the parent.";
-    try runner.testCases(&.{
-        .{ "let content = document.getElementById('content')", "undefined" },
-        .{ "let link = document.getElementById('link')", "undefined" },
-        // HierarchyRequestError
-        .{
-            \\ var he;
-            \\ try { link.appendChild(content) } catch (error) { he = error}
-            \\ he.name
-            ,
-            "HierarchyRequestError",
-        },
-        .{ "he.code", "3" },
-        .{ "he.message", err },
-        .{ "he.toString()", "HierarchyRequestError: " ++ err },
-        .{ "he instanceof DOMException", "true" },
-        .{ "he instanceof Error", "true" },
-    }, .{});
+test "Browser: DOM.Exceptions" {
+    try testing.htmlRunner("dom/exceptions.html");
 }

src/browser/dom/html_collection.zig

@@ -72,13 +72,14 @@ pub fn HTMLCollectionByTagName(
     arena: Allocator,
     root: ?*parser.Node,
     tag_name: []const u8,
-    include_root: bool,
+    opts: Opts,
 ) !HTMLCollection {
     return HTMLCollection{
         .root = root,
         .walker = .{ .walkerDepthFirst = .{} },
         .matcher = .{ .matchByTagName = try MatchByTagName.init(arena, tag_name) },
-        .include_root = include_root,
+        .mutable = opts.mutable,
+        .include_root = opts.include_root,
     };
 }
 
@@ -109,13 +110,14 @@ pub fn HTMLCollectionByClassName(
     arena: Allocator,
     root: ?*parser.Node,
     classNames: []const u8,
-    include_root: bool,
+    opts: Opts,
 ) !HTMLCollection {
     return HTMLCollection{
         .root = root,
         .walker = .{ .walkerDepthFirst = .{} },
         .matcher = .{ .matchByClassName = try MatchByClassName.init(arena, classNames) },
-        .include_root = include_root,
+        .mutable = opts.mutable,
+        .include_root = opts.include_root,
     };
 }
 
@@ -139,13 +141,14 @@ pub fn HTMLCollectionByName(
     arena: Allocator,
     root: ?*parser.Node,
     name: []const u8,
-    include_root: bool,
+    opts: Opts,
 ) !HTMLCollection {
     return HTMLCollection{
         .root = root,
         .walker = .{ .walkerDepthFirst = .{} },
         .matcher = .{ .matchByName = try MatchByName.init(arena, name) },
-        .include_root = include_root,
+        .mutable = opts.mutable,
+        .include_root = opts.include_root,
     };
 }
 
@@ -189,13 +192,14 @@ pub const HTMLAllCollection = struct {
 
 pub fn HTMLCollectionChildren(
     root: ?*parser.Node,
-    include_root: bool,
-) !HTMLCollection {
+    opts: Opts,
+) HTMLCollection {
     return HTMLCollection{
         .root = root,
         .walker = .{ .walkerChildren = .{} },
         .matcher = .{ .matchTrue = .{} },
-        .include_root = include_root,
+        .mutable = opts.mutable,
+        .include_root = opts.include_root,
     };
 }
 
@@ -224,13 +228,14 @@ pub const MatchByLinks = struct {
 
 pub fn HTMLCollectionByLinks(
     root: ?*parser.Node,
-    include_root: bool,
+    opts: Opts,
 ) !HTMLCollection {
     return HTMLCollection{
         .root = root,
         .walker = .{ .walkerDepthFirst = .{} },
         .matcher = .{ .matchByLinks = MatchByLinks{} },
-        .include_root = include_root,
+        .mutable = opts.mutable,
+        .include_root = opts.include_root,
     };
 }
 
@@ -249,13 +254,14 @@ pub const MatchByAnchors = struct {
 
 pub fn HTMLCollectionByAnchors(
     root: ?*parser.Node,
-    include_root: bool,
+    opts: Opts,
 ) !HTMLCollection {
     return HTMLCollection{
         .root = root,
         .walker = .{ .walkerDepthFirst = .{} },
         .matcher = .{ .matchByAnchors = MatchByAnchors{} },
-        .include_root = include_root,
+        .mutable = opts.mutable,
+        .include_root = opts.include_root,
     };
 }
 
@@ -285,6 +291,11 @@ pub const HTMLCollectionIterator = struct {
     }
 };
 
+const Opts = struct {
+    include_root: bool,
+    mutable: bool = false,
+};
+
 // WEB IDL https://dom.spec.whatwg.org/#htmlcollection
 // HTMLCollection is re implemented in zig here because libdom
 // dom_html_collection expects a comparison function callback as arguement.
@@ -300,6 +311,8 @@ pub const HTMLCollection = struct {
     // itself.
     include_root: bool = false,
 
+    mutable: bool = false,
+
     // save a state for the collection to improve the _item speed.
     cur_idx: ?u32 = null,
     cur_node: ?*parser.Node = null,
@@ -350,7 +363,7 @@ pub const HTMLCollection = struct {
         var node: *parser.Node = undefined;
 
         // Use the current state to improve speed if possible.
-        if (self.cur_idx != null and index >= self.cur_idx.?) {
+        if (self.mutable == false and self.cur_idx != null and index >= self.cur_idx.?) {
             i = self.cur_idx.?;
             node = self.cur_node.?;
         } else {
@@ -449,52 +462,6 @@ pub const HTMLCollection = struct {
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.HTMLCollection" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let getElementsByTagName = document.getElementsByTagName('p')", "undefined" },
-        .{ "getElementsByTagName.length", "2" },
-        .{ "let getElementsByTagNameCI = document.getElementsByTagName('P')", "undefined" },
-        .{ "getElementsByTagNameCI.length", "2" },
-        .{ "getElementsByTagName.item(0).localName", "p" },
-        .{ "getElementsByTagName.item(1).localName", "p" },
-        .{ "let getElementsByTagNameAll = document.getElementsByTagName('*')", "undefined" },
-        .{ "getElementsByTagNameAll.length", "8" },
-        .{ "getElementsByTagNameAll.item(0).localName", "html" },
-        .{ "getElementsByTagNameAll.item(0).localName", "html" },
-        .{ "getElementsByTagNameAll.item(1).localName", "head" },
-        .{ "getElementsByTagNameAll.item(0).localName", "html" },
-        .{ "getElementsByTagNameAll.item(2).localName", "body" },
-        .{ "getElementsByTagNameAll.item(3).localName", "div" },
-        .{ "getElementsByTagNameAll.item(7).localName", "p" },
-        .{ "getElementsByTagNameAll.namedItem('para-empty-child').localName", "span" },
-
-        // array like
-        .{ "getElementsByTagNameAll[0].localName", "html" },
-        .{ "getElementsByTagNameAll[7].localName", "p" },
-        .{ "getElementsByTagNameAll[8]", "undefined" },
-        .{ "getElementsByTagNameAll['para-empty-child'].localName", "span" },
-        .{ "getElementsByTagNameAll['foo']", "undefined" },
-
-        .{ "document.getElementById('content').getElementsByTagName('*').length", "4" },
-        .{ "document.getElementById('content').getElementsByTagName('p').length", "2" },
-        .{ "document.getElementById('content').getElementsByTagName('div').length", "0" },
-
-        .{ "document.children.length", "1" },
-        .{ "document.getElementById('content').children.length", "3" },
-
-        // check liveness
-        .{ "let content = document.getElementById('content')", "undefined" },
-        .{ "let pe = document.getElementById('para-empty')", "undefined" },
-        .{ "let p = document.createElement('p')", "undefined" },
-        .{ "p.textContent = 'OK live'", "OK live" },
-        .{ "getElementsByTagName.item(1).textContent", " And" },
-        .{ "content.appendChild(p) != undefined", "true" },
-        .{ "getElementsByTagName.length", "3" },
-        .{ "getElementsByTagName.item(2).textContent", "OK live" },
-        .{ "content.insertBefore(p, pe) != undefined", "true" },
-        .{ "getElementsByTagName.item(0).textContent", "OK live" },
-    }, .{});
+test "Browser: DOM.HTMLCollection" {
+    try testing.htmlRunner("dom/html_collection.html");
 }

src/browser/dom/implementation.zig

@@ -50,23 +50,7 @@ pub const DOMImplementation = struct {
     }
 };
 
-// Tests
-// -----
-
 const testing = @import("../../testing.zig");
-test "Browser.DOM.Implementation" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let impl = document.implementation", "undefined" },
-        .{ "impl.createHTMLDocument();", "[object HTMLDocument]" },
-        .{ "const doc = impl.createHTMLDocument('foo');", "undefined" },
-        .{ "doc", "[object HTMLDocument]" },
-        .{ "doc.title", "foo" },
-        .{ "doc.body", "[object HTMLBodyElement]" },
-        .{ "impl.createDocument(null, 'foo');", "[object Document]" },
-        .{ "impl.createDocumentType('foo', 'bar', 'baz')", "[object DocumentType]" },
-        .{ "impl.hasFeature()", "true" },
-    }, .{});
+test "Browser: DOM.Implementation" {
+    try testing.htmlRunner("dom/implementation.html");
 }

src/browser/dom/intersection_observer.zig

@@ -181,110 +181,6 @@ pub const IntersectionObserverEntry = struct {
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.IntersectionObserver" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "new IntersectionObserver(() => {}).observe(document.documentElement);", "undefined" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "let count_a = 0;", "undefined" },
-        .{ "const a1 = document.createElement('div');", "undefined" },
-        .{ "new IntersectionObserver(entries => {count_a += 1;}).observe(a1);", "undefined" },
-        .{ "count_a;", "1" },
-    }, .{});
-
-    // This test is documenting current behavior, not correct behavior.
-    // Currently every time observe is called, the callback is called with all entries.
-    try runner.testCases(&.{
-        .{ "let count_b = 0;", "undefined" },
-        .{ "let observer_b = new IntersectionObserver(entries => {count_b = entries.length;});", "undefined" },
-        .{ "const b1 = document.createElement('div');", "undefined" },
-        .{ "observer_b.observe(b1);", "undefined" },
-        .{ "count_b;", "1" },
-        .{ "const b2 = document.createElement('div');", "undefined" },
-        .{ "observer_b.observe(b2);", "undefined" },
-        .{ "count_b;", "2" },
-    }, .{});
-
-    // Re-observing is a no-op
-    try runner.testCases(&.{
-        .{ "let count_bb = 0;", "undefined" },
-        .{ "let observer_bb = new IntersectionObserver(entries => {count_bb = entries.length;});", "undefined" },
-        .{ "const bb1 = document.createElement('div');", "undefined" },
-        .{ "observer_bb.observe(bb1);", "undefined" },
-        .{ "count_bb;", "1" },
-        .{ "observer_bb.observe(bb1);", "undefined" },
-        .{ "count_bb;", "1" }, // Still 1, not 2
-    }, .{});
-
-    // Unobserve
-    try runner.testCases(&.{
-        .{ "let count_c = 0;", "undefined" },
-        .{ "let observer_c = new IntersectionObserver(entries => { count_c = entries.length;});", "undefined" },
-        .{ "const c1 = document.createElement('div');", "undefined" },
-        .{ "observer_c.observe(c1);", "undefined" },
-        .{ "count_c;", "1" },
-        .{ "observer_c.unobserve(c1);", "undefined" },
-        .{ "const c2 = document.createElement('div');", "undefined" },
-        .{ "observer_c.observe(c2);", "undefined" },
-        .{ "count_c;", "1" },
-    }, .{});
-
-    // Disconnect
-    try runner.testCases(&.{
-        .{ "let observer_d = new IntersectionObserver(entries => {});", "undefined" },
-        .{ "let d1 = document.createElement('div');", "undefined" },
-        .{ "observer_d.observe(d1);", "undefined" },
-        .{ "observer_d.disconnect();", "undefined" },
-        .{ "observer_d.takeRecords().length;", "0" },
-    }, .{});
-
-    // takeRecords
-    try runner.testCases(&.{
-        .{ "let observer_e = new IntersectionObserver(entries => {});", "undefined" },
-        .{ "let e1 = document.createElement('div');", "undefined" },
-        .{ "observer_e.observe(e1);", "undefined" },
-        .{ "const e2 = document.createElement('div');", "undefined" },
-        .{ "observer_e.observe(e2);", "undefined" },
-        .{ "observer_e.takeRecords().length;", "2" },
-    }, .{});
-
-    // Entry
-    try runner.testCases(&.{
-        .{ "let entry;", "undefined" },
-        .{ "let div1 = document.createElement('div')", null },
-        .{ "document.body.appendChild(div1);", null },
-        .{ "new IntersectionObserver(entries => { entry = entries[0]; }).observe(div1);", null },
-        .{ "entry.boundingClientRect.x;", "0" },
-        .{ "entry.intersectionRatio;", "1" },
-        .{ "entry.intersectionRect.x;", "0" },
-        .{ "entry.intersectionRect.y;", "0" },
-        .{ "entry.intersectionRect.width;", "1" },
-        .{ "entry.intersectionRect.height;", "1" },
-        .{ "entry.isIntersecting;", "true" },
-        .{ "entry.rootBounds.x;", "0" },
-        .{ "entry.rootBounds.y;", "0" },
-        .{ "entry.rootBounds.width;", "1" },
-        .{ "entry.rootBounds.height;", "1" },
-        .{ "entry.target;", "[object HTMLDivElement]" },
-    }, .{});
-
-    // Options
-    try runner.testCases(&.{
-        .{ "const new_root = document.createElement('span');", null },
-        .{ "document.body.appendChild(new_root);", null },
-        .{ "let new_entry;", "undefined" },
-        .{
-            \\ const new_observer = new IntersectionObserver(
-            \\ entries => { new_entry = entries[0]; },
-            \\ {root: new_root, rootMargin: '0px 0px 0px 0px', threshold: [0]});
-            ,
-            "undefined",
-        },
-        .{ "new_observer.observe(document.createElement('div'));", "undefined" },
-        .{ "new_entry.rootBounds.x;", "1" },
-    }, .{});
+test "Browser: DOM.IntersectionObserver" {
+    try testing.htmlRunner("dom/intersection_observer.html");
 }

src/browser/dom/mutation_observer.zig

@@ -35,25 +35,33 @@ const Walker = @import("../dom/walker.zig").WalkerChildren;
 
 // WEB IDL https://dom.spec.whatwg.org/#interface-mutationobserver
 pub const MutationObserver = struct {
+    page: *Page,
     cbk: Env.Function,
-    arena: Allocator,
+    connected: bool,
+    scheduled: bool,
 
     // List of records which were observed. When the call scope ends, we need to
     // execute our callback with it.
-    observed: std.ArrayListUnmanaged(*MutationRecord),
+    observed: std.ArrayListUnmanaged(MutationRecord),
 
     pub fn constructor(cbk: Env.Function, page: *Page) !MutationObserver {
         return .{
             .cbk = cbk,
+            .page = page,
             .observed = .{},
-            .arena = page.arena,
+            .connected = true,
+            .scheduled = false,
         };
     }
 
-    pub fn _observe(self: *MutationObserver, node: *parser.Node, options_: ?MutationObserverInit) !void {
-        const options = options_ orelse MutationObserverInit{};
+    pub fn _observe(self: *MutationObserver, node: *parser.Node, options_: ?Options) !void {
+        const arena = self.page.arena;
+        var options = options_ orelse Options{};
+        if (options.attributeFilter.len > 0) {
+            options.attributeFilter = try arena.dupe([]const u8, options.attributeFilter);
+        }
 
-        const observer = try self.arena.create(Observer);
+        const observer = try arena.create(Observer);
         observer.* = .{
             .node = node,
             .options = options,
@@ -102,30 +110,35 @@ pub const MutationObserver = struct {
         }
     }
 
-    pub fn jsCallScopeEnd(self: *MutationObserver) void {
-        const record = self.observed.items;
-        if (record.len == 0) {
-            return;
+    fn callback(ctx: *anyopaque) ?u32 {
+        const self: *MutationObserver = @ptrCast(@alignCast(ctx));
+        if (self.connected == false) {
+            self.scheduled = true;
+            return null;
+        }
+        self.scheduled = false;
+
+        const records = self.observed.items;
+        if (records.len == 0) {
+            return null;
         }
 
         defer self.observed.clearRetainingCapacity();
 
-        for (record) |r| {
-            const records = [_]MutationRecord{r.*};
-            var result: Env.Function.Result = undefined;
-            self.cbk.tryCall(void, .{records}, &result) catch {
-                log.debug(.user_script, "callback error", .{
-                    .err = result.exception,
-                    .stack = result.stack,
-                    .source = "mutation observer",
-                });
-            };
-        }
+        var result: Env.Function.Result = undefined;
+        self.cbk.tryCall(void, .{records}, &result) catch {
+            log.debug(.user_script, "callback error", .{
+                .err = result.exception,
+                .stack = result.stack,
+                .source = "mutation observer",
+            });
+        };
+        return null;
     }
 
     // TODO
-    pub fn _disconnect(_: *MutationObserver) !void {
-        // TODO unregister listeners.
+    pub fn _disconnect(self: *MutationObserver) !void {
+        self.connected = false;
     }
 
     // TODO
@@ -182,31 +195,27 @@ pub const MutationRecord = struct {
     }
 };
 
-const MutationObserverInit = struct {
+const Options = struct {
     childList: bool = false,
     attributes: bool = false,
     characterData: bool = false,
     subtree: bool = false,
     attributeOldValue: bool = false,
     characterDataOldValue: bool = false,
-    // TODO
-    // attributeFilter: [][]const u8,
+    attributeFilter: [][]const u8 = &.{},
 
-    fn attr(self: MutationObserverInit) bool {
-        return self.attributes or self.attributeOldValue;
+    fn attr(self: Options) bool {
+        return self.attributes or self.attributeOldValue or self.attributeFilter.len > 0;
     }
 
-    fn cdata(self: MutationObserverInit) bool {
+    fn cdata(self: Options) bool {
         return self.characterData or self.characterDataOldValue;
     }
 };
 
 const Observer = struct {
     node: *parser.Node,
-    options: MutationObserverInit,
-
-    // record of the mutation, all observed changes in 1 call are batched
-    record: ?MutationRecord = null,
+    options: Options,
 
     // reference back to the MutationObserver so that we can access the arena
     // and batch the mutation records.
@@ -214,19 +223,34 @@ const Observer = struct {
 
     event_node: parser.EventNode,
 
-    fn appliesTo(o: *const Observer, target: *parser.Node) bool {
+    fn appliesTo(
+        self: *const Observer,
+        target: *parser.Node,
+        event_type: MutationEventType,
+        event: *parser.MutationEvent,
+    ) !bool {
+        if (event_type == .DOMAttrModified and self.options.attributeFilter.len > 0) {
+            const attribute_name = try parser.mutationEventAttributeName(event);
+            for (self.options.attributeFilter) |needle| blk: {
+                if (std.mem.eql(u8, attribute_name, needle)) {
+                    break :blk;
+                }
+            }
+            return false;
+        }
+
         // mutation on any target is always ok.
-        if (o.options.subtree) {
+        if (self.options.subtree) {
             return true;
         }
 
         // if target equals node, alway ok.
-        if (target == o.node) {
+        if (target == self.node) {
             return true;
         }
 
         // no subtree, no same target and no childlist, always noky.
-        if (!o.options.childList) {
+        if (!self.options.childList) {
             return false;
         }
 
@@ -234,7 +258,7 @@ const Observer = struct {
         const walker = Walker{};
         var next: ?*parser.Node = null;
         while (true) {
-            next = walker.get_next(o.node, next) catch break orelse break;
+            next = walker.get_next(self.node, next) catch break orelse break;
             if (next.? == target) {
                 return true;
             }
@@ -258,27 +282,22 @@ const Observer = struct {
             break :blk parser.eventTargetToNode(event_target);
         };
 
-        if (self.appliesTo(node) == false) {
-            return;
-        }
-
+        const mutation_event = parser.eventToMutationEvent(event);
         const event_type = blk: {
             const t = try parser.eventType(event);
             break :blk std.meta.stringToEnum(MutationEventType, t) orelse return;
         };
 
-        const arena = mutation_observer.arena;
-        if (self.record == null) {
-            self.record = .{
-                .target = self.node,
-                .type = event_type.recordType(),
-            };
-            try mutation_observer.observed.append(arena, &self.record.?);
+        if (try self.appliesTo(node, event_type, mutation_event) == false) {
+            return;
         }
 
-        var record = &self.record.?;
-        const mutation_event = parser.eventToMutationEvent(event);
+        var record = MutationRecord{
+            .target = self.node,
+            .type = event_type.recordType(),
+        };
 
+        const arena = mutation_observer.page.arena;
         switch (event_type) {
             .DOMAttrModified => {
                 record.attribute_name = parser.mutationEventAttributeName(mutation_event) catch null;
@@ -302,6 +321,18 @@ const Observer = struct {
                 }
             },
         }
+
+        try mutation_observer.observed.append(arena, record);
+
+        if (mutation_observer.scheduled == false) {
+            mutation_observer.scheduled = true;
+            try mutation_observer.page.scheduler.add(
+                mutation_observer,
+                MutationObserver.callback,
+                0,
+                .{ .name = "mutation_observer" },
+            );
+        }
     }
 };
 
@@ -322,68 +353,6 @@ const MutationEventType = enum {
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.DOM.MutationObserver" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "new MutationObserver(() => {}).observe(document, { childList: true });", "undefined" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{
-            \\ var nb = 0;
-            \\ var mrs;
-            \\ new MutationObserver((mu) => {
-            \\    mrs = mu;
-            \\    nb++;
-            \\ }).observe(document.firstElementChild, { attributes: true, attributeOldValue: true });
-            \\ document.firstElementChild.setAttribute("foo", "bar");
-            \\ // ignored b/c it's about another target.
-            \\ document.firstElementChild.firstChild.setAttribute("foo", "bar");
-            \\ nb;
-            ,
-            "1",
-        },
-        .{ "mrs[0].type", "attributes" },
-        .{ "mrs[0].target == document.firstElementChild", "true" },
-        .{ "mrs[0].target.getAttribute('foo')", "bar" },
-        .{ "mrs[0].attributeName", "foo" },
-        .{ "mrs[0].oldValue", "null" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{
-            \\ var node = document.getElementById("para").firstChild;
-            \\ var nb2 = 0;
-            \\ var mrs2;
-            \\ new MutationObserver((mu) => {
-            \\     mrs2 = mu;
-            \\     nb2++;
-            \\ }).observe(node, { characterData: true, characterDataOldValue: true });
-            \\ node.data = "foo";
-            \\ nb2;
-            ,
-            "1",
-        },
-        .{ "mrs2[0].type", "characterData" },
-        .{ "mrs2[0].target == node", "true" },
-        .{ "mrs2[0].target.data", "foo" },
-        .{ "mrs2[0].oldValue", " And" },
-    }, .{});
-
-    // tests that mutation observers that have a callback which trigger the
-    // mutation observer don't crash.
-    // https://github.com/lightpanda-io/browser/issues/550
-    try runner.testCases(&.{
-        .{
-            \\ var node = document.getElementById("para");
-            \\ new MutationObserver(() => {
-            \\     node.innerText = 'a';
-            \\ }).observe(document, { subtree:true,childList:true });
-            \\ node.innerText = "2";
-            ,
-            "2",
-        },
-    }, .{});
+test "Browser: DOM.MutationObserver" {
+    try testing.htmlRunner("dom/mutation_observer.html");
 }

src/browser/dom/namednodemap.zig

@@ -115,24 +115,7 @@ pub const NamedNodeMapIterator = struct {
     }
 };
 
-// Tests
-// -----
-
 const testing = @import("../../testing.zig");
-test "Browser.DOM.NamedNodeMap" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let a = document.getElementById('content').attributes", "undefined" },
-        .{ "a.length", "1" },
-        .{ "a.item(0)", "[object Attr]" },
-        .{ "a.item(1)", "null" },
-        .{ "a.getNamedItem('id')", "[object Attr]" },
-        .{ "a.getNamedItem('foo')", "null" },
-        .{ "a.setNamedItem(a.getNamedItem('id'))", "[object Attr]" },
-        .{ "a['id'].name", "id" },
-        .{ "a['id'].value", "content" },
-        .{ "a['other']", "undefined" },
-    }, .{});
+test "Browser: DOM.NamedNodeMap" {
+    try testing.htmlRunner("dom/named_node_map.html");
 }

src/browser/dom/node.zig

@@ -29,6 +29,7 @@ const EventTarget = @import("event_target.zig").EventTarget;
 const Attr = @import("attribute.zig").Attr;
 const CData = @import("character_data.zig");
 const Element = @import("element.zig").Element;
+const ElementUnion = @import("element.zig").Union;
 const NodeList = @import("nodelist.zig").NodeList;
 const Document = @import("document.zig").Document;
 const DocumentType = @import("document_type.zig").DocumentType;
@@ -36,11 +37,11 @@ const DocumentFragment = @import("document_fragment.zig").DocumentFragment;
 const HTMLCollection = @import("html_collection.zig").HTMLCollection;
 const HTMLAllCollection = @import("html_collection.zig").HTMLAllCollection;
 const HTMLCollectionIterator = @import("html_collection.zig").HTMLCollectionIterator;
+const ShadowRoot = @import("shadow_root.zig").ShadowRoot;
 const Walker = @import("walker.zig").WalkerDepthFirst;
 
 // HTML
 const HTML = @import("../html/html.zig");
-const HTMLElem = @import("../html/elements.zig");
 
 // Node interfaces
 pub const Interfaces = .{
@@ -67,7 +68,7 @@ pub const Node = struct {
 
     pub fn toInterface(node: *parser.Node) !Union {
         return switch (try parser.nodeType(node)) {
-            .element => try HTMLElem.toInterface(
+            .element => try Element.toInterfaceT(
                 Union,
                 @as(*parser.Element, @ptrCast(node)),
             ),
@@ -75,7 +76,14 @@ pub const Node = struct {
             .text => .{ .Text = @as(*parser.Text, @ptrCast(node)) },
             .cdata_section => .{ .CDATASection = @as(*parser.CDATASection, @ptrCast(node)) },
             .processing_instruction => .{ .ProcessingInstruction = @as(*parser.ProcessingInstruction, @ptrCast(node)) },
-            .document => .{ .HTMLDocument = @as(*parser.DocumentHTML, @ptrCast(node)) },
+            .document => blk: {
+                const doc: *parser.Document = @ptrCast(node);
+                if (doc.is_html) {
+                    break :blk .{ .HTMLDocument = @as(*parser.DocumentHTML, @ptrCast(node)) };
+                }
+
+                break :blk .{ .Document = doc };
+            },
             .document_type => .{ .DocumentType = @as(*parser.DocumentType, @ptrCast(node)) },
             .attribute => .{ .Attr = @as(*parser.Attribute, @ptrCast(node)) },
             .document_fragment => .{ .DocumentFragment = @as(*parser.DocumentFragment, @ptrCast(node)) },
@@ -100,10 +108,20 @@ pub const Node = struct {
     pub const _ENTITY_NODE = @intFromEnum(parser.NodeType.entity);
     pub const _NOTATION_NODE = @intFromEnum(parser.NodeType.notation);
 
+    pub const _DOCUMENT_POSITION_DISCONNECTED = @intFromEnum(parser.DocumentPosition.disconnected);
+    pub const _DOCUMENT_POSITION_PRECEDING = @intFromEnum(parser.DocumentPosition.preceding);
+    pub const _DOCUMENT_POSITION_FOLLOWING = @intFromEnum(parser.DocumentPosition.following);
+    pub const _DOCUMENT_POSITION_CONTAINS = @intFromEnum(parser.DocumentPosition.contains);
+    pub const _DOCUMENT_POSITION_CONTAINED_BY = @intFromEnum(parser.DocumentPosition.contained_by);
+    pub const _DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC = @intFromEnum(parser.DocumentPosition.implementation_specific);
+
     // JS funcs
     // --------
 
     // Read-only attributes
+    pub fn get_baseURI(_: *parser.Node, page: *Page) ![]const u8 {
+        return page.url.raw;
+    }
 
     pub fn get_firstChild(self: *parser.Node) !?Union {
         const res = try parser.nodeFirstChild(self);
@@ -145,12 +163,12 @@ pub const Node = struct {
         return try Node.toInterface(res.?);
     }
 
-    pub fn get_parentElement(self: *parser.Node) !?HTMLElem.Union {
+    pub fn get_parentElement(self: *parser.Node) !?ElementUnion {
         const res = try parser.nodeParentElement(self);
         if (res == null) {
             return null;
         }
-        return try HTMLElem.toInterface(HTMLElem.Union, @as(*parser.Element, @ptrCast(res.?)));
+        return try Element.toInterface(res.?);
     }
 
     pub fn get_nodeName(self: *parser.Node) ![]const u8 {
@@ -170,11 +188,35 @@ pub const Node = struct {
     }
 
     pub fn get_isConnected(self: *parser.Node) !bool {
-        // TODO: handle Shadow DOM
-        if (try parser.nodeType(self) == .document) {
-            return true;
+        var node = self;
+        while (true) {
+            const node_type = try parser.nodeType(node);
+            if (node_type == .document) {
+                return true;
+            }
+
+            if (try parser.nodeParentNode(node)) |parent| {
+                // didn't find a document, but node has a parent, let's see
+                // if it's connected;
+                node = parent;
+                continue;
+            }
+
+            if (node_type != .document_fragment) {
+                // doesn't have a parent and isn't a document_fragment
+                // can't be connected
+                return false;
+            }
+
+            if (parser.documentFragmentGetHost(@ptrCast(node))) |host| {
+                // node doesn't have a parent, but it's a document fragment
+                // with a host. The host is like the parent, but we only want to
+                // traverse up (or down) to it in specific cases, like isConnected.
+                node = host;
+                continue;
+            }
+            return false;
         }
-        return try Node.get_parentNode(self) != null;
     }
 
     // Read/Write attributes
@@ -198,6 +240,23 @@ pub const Node = struct {
     // Methods
 
     pub fn _appendChild(self: *parser.Node, child: *parser.Node) !Union {
+        const self_owner = try parser.nodeOwnerDocument(self);
+        const child_owner = try parser.nodeOwnerDocument(child);
+
+        // If the node to be inserted has a different ownerDocument than the parent node,
+        // modern browsers automatically adopt the node and its descendants into
+        // the parent's ownerDocument.
+        // This process is known as adoption.
+        // (7.1) https://dom.spec.whatwg.org/#concept-node-insert
+        if (child_owner == null or (self_owner != null and child_owner.? != self_owner.?)) {
+            const w = Walker{};
+            var current = child;
+            while (true) {
+                current.owner = self_owner;
+                current = try w.get_next(child, current) orelse break;
+            }
+        }
+
         // TODO: DocumentFragment special case
         const res = try parser.nodeAppendChild(self, child);
         return try Node.toInterface(res);
@@ -209,14 +268,43 @@ pub const Node = struct {
     }
 
     pub fn _compareDocumentPosition(self: *parser.Node, other: *parser.Node) !u32 {
-        if (self == other) return 0;
+        if (self == other) {
+            return 0;
+        }
 
-        const docself = try parser.nodeOwnerDocument(self);
-        const docother = try parser.nodeOwnerDocument(other);
+        const docself = try parser.nodeOwnerDocument(self) orelse blk: {
+            if (try parser.nodeType(self) == .document) {
+                break :blk @as(*parser.Document, @ptrCast(self));
+            }
+            break :blk null;
+        };
+        const docother = try parser.nodeOwnerDocument(other) orelse blk: {
+            if (try parser.nodeType(other) == .document) {
+                break :blk @as(*parser.Document, @ptrCast(other));
+            }
+            break :blk null;
+        };
 
         // Both are in different document.
-        if (docself == null or docother == null or docother.? != docself.?) {
-            return @intFromEnum(parser.DocumentPosition.disconnected);
+        if (docself == null or docother == null or docself.? != docother.?) {
+            return @intFromEnum(parser.DocumentPosition.disconnected) +
+                @intFromEnum(parser.DocumentPosition.implementation_specific) +
+                @intFromEnum(parser.DocumentPosition.preceding);
+        }
+
+        if (@intFromPtr(self) == @intFromPtr(docself.?)) {
+            // if self is the document, and we already know other is in the
+            // document, then other is contained by and following self.
+            return @intFromEnum(parser.DocumentPosition.following) +
+                @intFromEnum(parser.DocumentPosition.contained_by);
+        }
+
+        const rootself = try parser.nodeGetRootNode(self);
+        const rootother = try parser.nodeGetRootNode(other);
+        if (rootself != rootother) {
+            return @intFromEnum(parser.DocumentPosition.disconnected) +
+                @intFromEnum(parser.DocumentPosition.implementation_specific) +
+                @intFromEnum(parser.DocumentPosition.preceding);
         }
 
         // TODO Both are in a different trees in the same document.
@@ -267,11 +355,23 @@ pub const Node = struct {
     // - An Element inside a standard web page will return an HTMLDocument object representing the entire page (or <iframe>).
     // - An Element inside a shadow DOM will return the associated ShadowRoot.
     // - An Element that is not attached to a document or a shadow tree will return the root of the DOM tree it belongs to
-    pub fn _getRootNode(self: *parser.Node, options: ?struct { composed: bool = false }) !Union {
+    const GetRootNodeResult = union(enum) {
+        shadow_root: *ShadowRoot,
+        node: Union,
+    };
+    pub fn _getRootNode(self: *parser.Node, options: ?struct { composed: bool = false }, page: *Page) !GetRootNodeResult {
         if (options) |options_| if (options_.composed) {
             log.warn(.web_api, "not implemented", .{ .feature = "getRootNode composed" });
         };
-        return try Node.toInterface(try parser.nodeGetRootNode(self));
+
+        const root = try parser.nodeGetRootNode(self);
+        if (page.getNodeState(root)) |state| {
+            if (state.shadow_root) |sr| {
+                return .{ .shadow_root = sr };
+            }
+        }
+
+        return .{ .node = try Node.toInterface(root) };
     }
 
     pub fn _hasChildNodes(self: *parser.Node) !bool {
@@ -290,10 +390,28 @@ pub const Node = struct {
     }
 
     pub fn _insertBefore(self: *parser.Node, new_node: *parser.Node, ref_node_: ?*parser.Node) !Union {
-        if (ref_node_) |ref_node| {
-            return Node.toInterface(try parser.nodeInsertBefore(self, new_node, ref_node));
+        if (ref_node_ == null) {
+            return _appendChild(self, new_node);
         }
-        return _appendChild(self, new_node);
+
+        const self_owner = try parser.nodeOwnerDocument(self);
+        const new_node_owner = try parser.nodeOwnerDocument(new_node);
+
+        // If the node to be inserted has a different ownerDocument than the parent node,
+        // modern browsers automatically adopt the node and its descendants into
+        // the parent's ownerDocument.
+        // This process is known as adoption.
+        // (7.1) https://dom.spec.whatwg.org/#concept-node-insert
+        if (new_node_owner == null or (self_owner != null and new_node_owner.? != self_owner.?)) {
+            const w = Walker{};
+            var current = new_node;
+            while (true) {
+                current.owner = self_owner;
+                current = try w.get_next(new_node, current) orelse break;
+            }
+        }
+
+        return Node.toInterface(try parser.nodeInsertBefore(self, new_node, ref_node_.?));
     }
 
     pub fn _isDefaultNamespace(self: *parser.Node, namespace: ?[]const u8) !bool {
@@ -496,7 +614,7 @@ pub const Node = struct {
         fn toNode(self: NodeOrText, doc: *parser.Document) !*parser.Node {
             return switch (self) {
                 .node => |n| n,
-                .text => |txt| @alignCast(@ptrCast(try parser.documentCreateTextNode(doc, txt))),
+                .text => |txt| @ptrCast(@alignCast(try parser.documentCreateTextNode(doc, txt))),
             };
         }
 
@@ -607,7 +725,13 @@ test "Browser.DOM.node" {
     try runner.testCases(&.{
         .{ "content.isConnected", "true" },
         .{ "document.isConnected", "true" },
-        .{ "document.createElement('div').isConnected", "false" },
+        .{ "const connDiv = document.createElement('div')", null },
+        .{ "connDiv.isConnected", "false" },
+        .{ "const connParentDiv = document.createElement('div')", null },
+        .{ "connParentDiv.appendChild(connDiv)", null },
+        .{ "connDiv.isConnected", "false" },
+        .{ "content.appendChild(connParentDiv)", null },
+        .{ "connDiv.isConnected", "true" },
     }, .{});
 
     try runner.testCases(&.{
@@ -695,6 +819,10 @@ test "Browser.DOM.node" {
         .{ "link.normalize()", "undefined" },
     }, .{});
 
+    try runner.testCases(&.{
+        .{ "link.baseURI", "https://lightpanda.io/opensource-browser/" },
+    }, .{});
+
     try runner.testCases(&.{
         .{ "content.removeChild(append) !== undefined", "true" },
         .{ "last_child.__proto__.constructor.name !== 'HTMLHeadingElement'", "true" },
@@ -720,3 +848,45 @@ test "Browser.DOM.node" {
         .{ "Node.NOTATION_NODE", "12" },
     }, .{});
 }
+
+test "Browser.DOM.node.owner" {
+    var runner = try testing.jsRunner(testing.tracking_allocator, .{ .html = 
+        \\  <div id="target-container">
+        \\     <p id="reference-node">
+        \\         I am the original reference node.
+        \\     </p>
+        \\  </div>"
+    });
+
+    defer runner.deinit();
+
+    try runner.testCases(&.{
+        .{
+            \\ const parser = new DOMParser();
+            \\ const newDoc = parser.parseFromString('<div id="new-node"><p>Hey</p><span>Marked</span></div>', 'text/html');
+            \\ const newNode = newDoc.getElementById('new-node');
+            \\ const parent = document.getElementById('target-container');
+            \\ const referenceNode = document.getElementById('reference-node');
+            \\ parent.insertBefore(newNode, referenceNode);
+            \\ const k = document.getElementById('new-node');
+            \\ const ptag = k.querySelector('p');
+            \\ const spanTag = k.querySelector('span');
+            \\ const anotherDoc = parser.parseFromString('<div id="another-new-node"></div>', 'text/html');
+            \\ const anotherNewNode = anotherDoc.getElementById('another-new-node');
+            \\
+            \\ parent.appendChild(anotherNewNode)
+            ,
+            "[object HTMLDivElement]",
+        },
+
+        .{ "parent.ownerDocument === newNode.ownerDocument", "true" },
+        .{ "parent.ownerDocument === anotherNewNode.ownerDocument", "true" },
+        .{ "newNode.firstChild.nodeName", "P" },
+        .{ "ptag.ownerDocument === parent.ownerDocument", "true" },
+        .{ "spanTag.ownerDocument === parent.ownerDocument", "true" },
+        .{ "parent.contains(newNode)", "true" },
+        .{ "parent.contains(anotherNewNode)", "true" },
+        .{ "anotherDoc.contains(anotherNewNode)", "false" },
+        .{ "newDoc.contains(newNode)", "false" },
+    }, .{});
+}

src/browser/dom/node_filter.zig

@@ -17,11 +17,15 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const parser = @import("../netsurf.zig");
+const Env = @import("../env.zig").Env;
+const Node = @import("node.zig").Node;
 
 pub const NodeFilter = struct {
     pub const _FILTER_ACCEPT: u16 = 1;
     pub const _FILTER_REJECT: u16 = 2;
     pub const _FILTER_SKIP: u16 = 3;
+
     pub const _SHOW_ALL: u32 = std.math.maxInt(u32);
     pub const _SHOW_ELEMENT: u32 = 0b1;
     pub const _SHOW_ATTRIBUTE: u32 = 0b10;
@@ -37,6 +41,39 @@ pub const NodeFilter = struct {
     pub const _SHOW_NOTATION: u32 = 0b100000000000;
 };
 
+const VerifyResult = enum { accept, skip, reject };
+
+pub fn verify(what_to_show: u32, filter: ?Env.Function, node: *parser.Node) !VerifyResult {
+    const node_type = try parser.nodeType(node);
+
+    // Verify that we can show this node type.
+    if (!switch (node_type) {
+        .attribute => what_to_show & NodeFilter._SHOW_ATTRIBUTE != 0,
+        .cdata_section => what_to_show & NodeFilter._SHOW_CDATA_SECTION != 0,
+        .comment => what_to_show & NodeFilter._SHOW_COMMENT != 0,
+        .document => what_to_show & NodeFilter._SHOW_DOCUMENT != 0,
+        .document_fragment => what_to_show & NodeFilter._SHOW_DOCUMENT_FRAGMENT != 0,
+        .document_type => what_to_show & NodeFilter._SHOW_DOCUMENT_TYPE != 0,
+        .element => what_to_show & NodeFilter._SHOW_ELEMENT != 0,
+        .entity => what_to_show & NodeFilter._SHOW_ENTITY != 0,
+        .entity_reference => what_to_show & NodeFilter._SHOW_ENTITY_REFERENCE != 0,
+        .notation => what_to_show & NodeFilter._SHOW_NOTATION != 0,
+        .processing_instruction => what_to_show & NodeFilter._SHOW_PROCESSING_INSTRUCTION != 0,
+        .text => what_to_show & NodeFilter._SHOW_TEXT != 0,
+    }) return .reject;
+
+    // Verify that we aren't filtering it out.
+    if (filter) |f| {
+        const acceptance = try f.call(u16, .{try Node.toInterface(node)});
+        return switch (acceptance) {
+            NodeFilter._FILTER_ACCEPT => .accept,
+            NodeFilter._FILTER_REJECT => .reject,
+            NodeFilter._FILTER_SKIP => .skip,
+            else => .reject,
+        };
+    } else return .accept;
+}
+
 const testing = @import("../../testing.zig");
 test "Browser.DOM.NodeFilter" {
     var runner = try testing.jsRunner(testing.tracking_allocator, .{});

src/browser/dom/node_iterator.zig

@@ -0,0 +1,338 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const parser = @import("../netsurf.zig");
+const Env = @import("../env.zig").Env;
+const NodeFilter = @import("node_filter.zig");
+const Node = @import("node.zig").Node;
+const NodeUnion = @import("node.zig").Union;
+const DOMException = @import("exceptions.zig").DOMException;
+
+// https://developer.mozilla.org/en-US/docs/Web/API/NodeIterator
+// While this is similar to TreeWalker it has its own implementation as there are several subtle differences
+// For example:
+// - nextNode returns the reference node, whereas TreeWalker returns the next node
+// - Skip and reject are equivalent for NodeIterator, for TreeWalker they are different
+pub const NodeIterator = struct {
+    pub const Exception = DOMException;
+
+    root: *parser.Node,
+    reference_node: *parser.Node,
+    what_to_show: u32,
+    filter: ?NodeIteratorOpts,
+    filter_func: ?Env.Function,
+    pointer_before_current: bool = true,
+    // used to track / block recursive filters
+    is_in_callback: bool = false,
+
+    // One of the few cases where null and undefined resolve to different default.
+    // We need the raw JsObject so that we can probe the tri state:
+    // null, undefined or i32.
+    pub const WhatToShow = Env.JsObject;
+
+    pub const NodeIteratorOpts = union(enum) {
+        function: Env.Function,
+        object: struct { acceptNode: Env.Function },
+    };
+
+    pub fn init(node: *parser.Node, what_to_show_: ?WhatToShow, filter: ?NodeIteratorOpts) !NodeIterator {
+        var filter_func: ?Env.Function = null;
+        if (filter) |f| {
+            filter_func = switch (f) {
+                .function => |func| func,
+                .object => |o| o.acceptNode,
+            };
+        }
+
+        var what_to_show: u32 = undefined;
+        if (what_to_show_) |wts| {
+            switch (try wts.triState(NodeIterator, "what_to_show", u32)) {
+                .null => what_to_show = 0,
+                .undefined => what_to_show = NodeFilter.NodeFilter._SHOW_ALL,
+                .value => |v| what_to_show = v,
+            }
+        } else {
+            what_to_show = NodeFilter.NodeFilter._SHOW_ALL;
+        }
+
+        return .{
+            .root = node,
+            .reference_node = node,
+            .what_to_show = what_to_show,
+            .filter = filter,
+            .filter_func = filter_func,
+        };
+    }
+
+    pub fn get_filter(self: *const NodeIterator) ?NodeIteratorOpts {
+        return self.filter;
+    }
+
+    pub fn get_pointerBeforeReferenceNode(self: *const NodeIterator) bool {
+        return self.pointer_before_current;
+    }
+
+    pub fn get_referenceNode(self: *const NodeIterator) !NodeUnion {
+        return try Node.toInterface(self.reference_node);
+    }
+
+    pub fn get_root(self: *const NodeIterator) !NodeUnion {
+        return try Node.toInterface(self.root);
+    }
+
+    pub fn get_whatToShow(self: *const NodeIterator) u32 {
+        return self.what_to_show;
+    }
+
+    pub fn _nextNode(self: *NodeIterator) !?NodeUnion {
+        try self.callbackStart();
+        defer self.callbackEnd();
+
+        if (self.pointer_before_current) {
+            // Unlike TreeWalker, NodeIterator starts at the first node
+            if (.accept == try NodeFilter.verify(self.what_to_show, self.filter_func, self.reference_node)) {
+                self.pointer_before_current = false;
+                return try Node.toInterface(self.reference_node);
+            }
+        }
+
+        if (try self.firstChild(self.reference_node)) |child| {
+            self.reference_node = child;
+            return try Node.toInterface(child);
+        }
+
+        var current = self.reference_node;
+        while (current != self.root) {
+            if (try self.nextSibling(current)) |sibling| {
+                self.reference_node = sibling;
+                return try Node.toInterface(sibling);
+            }
+
+            current = (try parser.nodeParentNode(current)) orelse break;
+        }
+
+        return null;
+    }
+
+    pub fn _previousNode(self: *NodeIterator) !?NodeUnion {
+        try self.callbackStart();
+        defer self.callbackEnd();
+
+        if (!self.pointer_before_current) {
+            if (.accept == try NodeFilter.verify(self.what_to_show, self.filter_func, self.reference_node)) {
+                self.pointer_before_current = true;
+                // Still need to verify as last may be first as well
+                return try Node.toInterface(self.reference_node);
+            }
+        }
+        if (self.reference_node == self.root) {
+            return null;
+        }
+
+        var current = self.reference_node;
+        while (try parser.nodePreviousSibling(current)) |previous| {
+            current = previous;
+
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, current)) {
+                .accept => {
+                    // Get last child if it has one.
+                    if (try self.lastChild(current)) |child| {
+                        self.reference_node = child;
+                        return try Node.toInterface(child);
+                    }
+
+                    // Otherwise, this node is our previous one.
+                    self.reference_node = current;
+                    return try Node.toInterface(current);
+                },
+                .reject, .skip => {
+                    // Get last child if it has one.
+                    if (try self.lastChild(current)) |child| {
+                        self.reference_node = child;
+                        return try Node.toInterface(child);
+                    }
+                },
+            }
+        }
+
+        if (current != self.root) {
+            if (try self.parentNode(current)) |parent| {
+                self.reference_node = parent;
+                return try Node.toInterface(parent);
+            }
+        }
+
+        return null;
+    }
+
+    pub fn _detach(self: *const NodeIterator) void {
+        // no-op as per spec
+        _ = self;
+    }
+
+    fn firstChild(self: *const NodeIterator, node: *parser.Node) !?*parser.Node {
+        const children = try parser.nodeGetChildNodes(node);
+        const child_count = try parser.nodeListLength(children);
+
+        for (0..child_count) |i| {
+            const index: u32 = @intCast(i);
+            const child = (try parser.nodeListItem(children, index)) orelse return null;
+
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, child)) {
+                .accept => return child, // NOTE: Skip and reject are equivalent for NodeIterator, this is different from TreeWalker
+                .reject, .skip => if (try self.firstChild(child)) |gchild| return gchild,
+            }
+        }
+
+        return null;
+    }
+
+    fn lastChild(self: *const NodeIterator, node: *parser.Node) !?*parser.Node {
+        const children = try parser.nodeGetChildNodes(node);
+        const child_count = try parser.nodeListLength(children);
+
+        var index: u32 = child_count;
+        while (index > 0) {
+            index -= 1;
+            const child = (try parser.nodeListItem(children, index)) orelse return null;
+
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, child)) {
+                .accept => return child, // NOTE: Skip and reject are equivalent for NodeIterator, this is different from TreeWalker
+                .reject, .skip => if (try self.lastChild(child)) |gchild| return gchild,
+            }
+        }
+
+        return null;
+    }
+
+    // This implementation is actually the same as :TreeWalker
+    fn parentNode(self: *const NodeIterator, node: *parser.Node) !?*parser.Node {
+        if (self.root == node) return null;
+
+        var current = node;
+        while (true) {
+            if (current == self.root) return null;
+            current = (try parser.nodeParentNode(current)) orelse return null;
+
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, current)) {
+                .accept => return current,
+                .reject, .skip => continue,
+            }
+        }
+    }
+
+    // This implementation is actually the same as :TreeWalker
+    fn nextSibling(self: *const NodeIterator, node: *parser.Node) !?*parser.Node {
+        var current = node;
+
+        while (true) {
+            current = (try parser.nodeNextSibling(current)) orelse return null;
+
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, current)) {
+                .accept => return current,
+                .skip, .reject => continue,
+            }
+        }
+
+        return null;
+    }
+
+    fn callbackStart(self: *NodeIterator) !void {
+        if (self.is_in_callback) {
+            // this is the correct DOMExeption
+            return error.InvalidState;
+        }
+        self.is_in_callback = true;
+    }
+
+    fn callbackEnd(self: *NodeIterator) void {
+        self.is_in_callback = false;
+    }
+};
+
+const testing = @import("../../testing.zig");
+test "Browser.DOM.NodeFilter" {
+    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
+    defer runner.deinit();
+
+    try runner.testCases(&.{
+        .{
+            \\ const nodeIterator = document.createNodeIterator(
+            \\   document.body,
+            \\   NodeFilter.SHOW_ELEMENT,
+            \\   {
+            \\     acceptNode(node) {
+            \\       return NodeFilter.FILTER_ACCEPT;
+            \\     },
+            \\   },
+            \\ );
+            \\ nodeIterator.nextNode().nodeName;
+            ,
+            "BODY",
+        },
+        .{ "nodeIterator.nextNode().nodeName", "DIV" },
+        .{ "nodeIterator.nextNode().nodeName", "A" },
+        .{ "nodeIterator.previousNode().nodeName", "A" }, // pointer_before_current flips
+        .{ "nodeIterator.nextNode().nodeName", "A" }, // pointer_before_current flips
+        .{ "nodeIterator.previousNode().nodeName", "A" }, // pointer_before_current flips
+        .{ "nodeIterator.previousNode().nodeName", "DIV" },
+        .{ "nodeIterator.previousNode().nodeName", "BODY" },
+        .{ "nodeIterator.previousNode()", "null" }, // Not HEAD since body is root
+        .{ "nodeIterator.previousNode()", "null" }, // Keeps returning null
+        .{ "nodeIterator.nextNode().nodeName", "BODY" },
+
+        .{ "nodeIterator.nextNode().nodeName", null },
+        .{ "nodeIterator.nextNode().nodeName", null },
+        .{ "nodeIterator.nextNode().nodeName", null },
+        .{ "nodeIterator.nextNode().nodeName", "SPAN" },
+        .{ "nodeIterator.nextNode().nodeName", "P" },
+        .{ "nodeIterator.nextNode()", "null" }, // Just the last one
+        .{ "nodeIterator.nextNode()", "null" }, // Keeps returning null
+        .{ "nodeIterator.previousNode().nodeName", "P" },
+    }, .{});
+
+    try runner.testCases(&.{
+        .{
+            \\ const notationIterator = document.createNodeIterator(
+            \\   document.body,
+            \\   NodeFilter.SHOW_NOTATION,
+            \\ );
+            \\ notationIterator.nextNode();
+            ,
+            "null",
+        },
+        .{ "notationIterator.previousNode()", "null" },
+    }, .{});
+
+    try runner.testCases(&.{
+        .{ "nodeIterator.filter.acceptNode(document.body)", "1" },
+        .{ "notationIterator.filter", "null" },
+        .{
+            \\ const rejectIterator = document.createNodeIterator(
+            \\   document.body,
+            \\   NodeFilter.SHOW_ALL,
+            \\   (e => { return NodeFilter.FILTER_REJECT}),
+            \\ );
+            \\ rejectIterator.filter(document.body);
+            ,
+            "2",
+        },
+    }, .{});
+}

src/browser/dom/nodelist.zig

@@ -110,7 +110,7 @@ pub const NodeList = struct {
         try self.nodes.append(alloc, node);
     }
 
-    pub fn get_length(self: *NodeList) u32 {
+    pub fn get_length(self: *const NodeList) u32 {
         return @intCast(self.nodes.items.len);
     }
 

src/browser/dom/performance.zig

@@ -20,53 +20,174 @@ const std = @import("std");
 
 const parser = @import("../netsurf.zig");
 const EventTarget = @import("../dom/event_target.zig").EventTarget;
+const Env = @import("../env.zig").Env;
+const Page = @import("../page.zig").Page;
+
+const milliTimestamp = @import("../../datetime.zig").milliTimestamp;
+
+pub const Interfaces = .{
+    Performance,
+    PerformanceEntry,
+    PerformanceMark,
+};
 
 // https://developer.mozilla.org/en-US/docs/Web/API/Performance
 pub const Performance = struct {
     pub const prototype = *EventTarget;
 
     // Extend libdom event target for pure zig struct.
-    base: parser.EventTargetTBase = parser.EventTargetTBase{},
+    base: parser.EventTargetTBase = parser.EventTargetTBase{ .internal_target_type = .performance },
 
-    time_origin: std.time.Timer,
+    time_origin: u64,
     // if (Window.crossOriginIsolated) -> Resolution in isolated contexts:       5 microseconds
     // else                            -> Resolution in non-isolated contexts: 100 microseconds
     const ms_resolution = 100;
 
-    fn limitedResolutionMs(nanoseconds: u64) f64 {
-        const elapsed_at_resolution = ((nanoseconds / std.time.ns_per_us) + ms_resolution / 2) / ms_resolution * ms_resolution;
-        const elapsed = @as(f64, @floatFromInt(elapsed_at_resolution));
-        return elapsed / @as(f64, std.time.us_per_ms);
-    }
-
-    pub fn get_timeOrigin(self: *const Performance) f64 {
-        const is_posix = switch (@import("builtin").os.tag) { // From std.time.zig L125
-            .windows, .uefi, .wasi => false,
-            else => true,
+    pub fn init() Performance {
+        return .{
+            .time_origin = milliTimestamp(),
         };
-        const zero = std.time.Instant{ .timestamp = if (!is_posix) 0 else .{ .sec = 0, .nsec = 0 } };
-        const started = self.time_origin.started.since(zero);
-        return limitedResolutionMs(started);
     }
 
-    pub fn _now(self: *Performance) f64 {
-        return limitedResolutionMs(self.time_origin.read());
+    pub fn get_timeOrigin(self: *const Performance) u64 {
+        return self.time_origin;
+    }
+
+    pub fn reset(self: *Performance) void {
+        self.time_origin = milliTimestamp();
+    }
+
+    pub fn _now(self: *const Performance) u64 {
+        return milliTimestamp() - self.time_origin;
+    }
+
+    pub fn _mark(_: *Performance, name: []const u8, _options: ?PerformanceMark.Options, page: *Page) !PerformanceMark {
+        const mark: PerformanceMark = try .constructor(name, _options, page);
+        // TODO: Should store this in an entries list
+        return mark;
+    }
+
+    // TODO: fn _mark should record the marks in a lookup
+    pub fn _clearMarks(_: *Performance, name: ?[]const u8) void {
+        _ = name;
+    }
+
+    // TODO: fn _measures should record the marks in a lookup
+    pub fn _clearMeasures(_: *Performance, name: ?[]const u8) void {
+        _ = name;
+    }
+
+    // TODO: fn _measures should record the marks in a lookup
+    pub fn _getEntriesByName(_: *Performance, name: []const u8, typ: ?[]const u8) []PerformanceEntry {
+        _ = name;
+        _ = typ;
+        return &.{};
+    }
+
+    // TODO: fn _measures should record the marks in a lookup
+    pub fn _getEntriesByType(_: *Performance, typ: []const u8) []PerformanceEntry {
+        _ = typ;
+        return &.{};
+    }
+};
+
+// https://developer.mozilla.org/en-US/docs/Web/API/PerformanceEntry
+pub const PerformanceEntry = struct {
+    const PerformanceEntryType = enum {
+        element,
+        event,
+        first_input,
+        largest_contentful_paint,
+        layout_shift,
+        long_animation_frame,
+        longtask,
+        mark,
+        measure,
+        navigation,
+        paint,
+        resource,
+        taskattribution,
+        visibility_state,
+
+        pub fn toString(self: PerformanceEntryType) []const u8 {
+            return switch (self) {
+                .first_input => "first-input",
+                .largest_contentful_paint => "largest-contentful-paint",
+                .layout_shift => "layout-shift",
+                .long_animation_frame => "long-animation-frame",
+                .visibility_state => "visibility-state",
+                else => @tagName(self),
+            };
+        }
+    };
+
+    duration: f64 = 0.0,
+    entry_type: PerformanceEntryType,
+    name: []const u8,
+    start_time: f64 = 0.0,
+
+    pub fn get_duration(self: *const PerformanceEntry) f64 {
+        return self.duration;
+    }
+
+    pub fn get_entryType(self: *const PerformanceEntry) PerformanceEntryType {
+        return self.entry_type;
+    }
+
+    pub fn get_name(self: *const PerformanceEntry) []const u8 {
+        return self.name;
+    }
+
+    pub fn get_startTime(self: *const PerformanceEntry) f64 {
+        return self.start_time;
+    }
+};
+
+// https://developer.mozilla.org/en-US/docs/Web/API/PerformanceMark
+pub const PerformanceMark = struct {
+    pub const prototype = *PerformanceEntry;
+
+    proto: PerformanceEntry,
+    detail: ?Env.JsObject,
+
+    const Options = struct {
+        detail: ?Env.JsObject = null,
+        startTime: ?f64 = null,
+    };
+
+    pub fn constructor(name: []const u8, _options: ?Options, page: *Page) !PerformanceMark {
+        const perf = &page.window.performance;
+
+        const options = _options orelse Options{};
+        const start_time = options.startTime orelse @as(f64, @floatFromInt(perf._now()));
+
+        if (start_time < 0.0) {
+            return error.TypeError;
+        }
+
+        const detail = if (options.detail) |d| try d.persist() else null;
+
+        const duped_name = try page.arena.dupe(u8, name);
+        const proto = PerformanceEntry{ .name = duped_name, .entry_type = .mark, .start_time = start_time };
+
+        return .{ .proto = proto, .detail = detail };
+    }
+
+    pub fn get_detail(self: *const PerformanceMark) ?Env.JsObject {
+        return self.detail;
     }
 };
 
 const testing = @import("./../../testing.zig");
 
 test "Performance: get_timeOrigin" {
-    var perf = Performance{ .time_origin = try std.time.Timer.start() };
+    var perf = Performance.init();
     const time_origin = perf.get_timeOrigin();
     try testing.expect(time_origin >= 0);
-
-    // Check resolution
-    try testing.expectDelta(@rem(time_origin * std.time.us_per_ms, 100.0), 0.0, 0.1);
 }
 
 test "Performance: now" {
-    var perf = Performance{ .time_origin = try std.time.Timer.start() };
+    var perf = Performance.init();
 
     // Monotonically increasing
     var now = perf._now();
@@ -74,14 +195,30 @@ test "Performance: now" {
         try testing.expectEqual(now, 0);
         now = perf._now();
     }
-    // Check resolution
-    try testing.expectDelta(@rem(now * std.time.us_per_ms, 100.0), 0.0, 0.1);
 
     var after = perf._now();
     while (after <= now) { // Loop untill after > now
         try testing.expectEqual(after, now);
         after = perf._now();
     }
-    // Check resolution
-    try testing.expectDelta(@rem(after * std.time.us_per_ms, 100.0), 0.0, 0.1);
+}
+
+test "Browser.Performance.Mark" {
+    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
+    defer runner.deinit();
+
+    try runner.testCases(&.{
+        .{ "let performance = window.performance", null },
+        .{ "performance instanceof Performance", "true" },
+
+        .{ "let mark1 = performance.mark(\"start\")", null },
+        .{ "mark1 instanceof PerformanceMark", "true" },
+        .{ "mark1.name", "start" },
+        .{ "mark1.entryType", "mark" },
+        .{ "mark1.duration", "0" },
+        .{ "mark1.detail", "null" },
+
+        .{ "let mark2 = performance.mark(\"start\", {startTime: 32939393.9})", null },
+        .{ "mark2.startTime", "32939393.9" },
+    }, .{});
 }

src/browser/dom/performance_observer.zig

@@ -17,10 +17,39 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const Env = @import("../env.zig").Env;
+
+const PerformanceEntry = @import("performance.zig").PerformanceEntry;
 
 // https://developer.mozilla.org/en-US/docs/Web/API/PerformanceObserver
 pub const PerformanceObserver = struct {
     pub const _supportedEntryTypes = [0][]const u8{};
+
+    pub fn constructor(cbk: Env.Function) PerformanceObserver {
+        _ = cbk;
+        return .{};
+    }
+
+    pub fn _observe(self: *const PerformanceObserver, options_: ?Options) void {
+        _ = self;
+        _ = options_;
+        return;
+    }
+
+    pub fn _disconnect(self: *PerformanceObserver) void {
+        _ = self;
+    }
+
+    pub fn _takeRecords(_: *const PerformanceObserver) []PerformanceEntry {
+        return &[_]PerformanceEntry{};
+    }
+};
+
+const Options = struct {
+    buffered: ?bool = null,
+    durationThreshold: ?f64 = null,
+    entryTypes: ?[]const []const u8 = null,
+    type: ?[]const u8 = null,
 };
 
 const testing = @import("../../testing.zig");

src/browser/dom/range.zig

@@ -0,0 +1,428 @@
+// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const parser = @import("../netsurf.zig");
+const Page = @import("../page.zig").Page;
+
+const Node = @import("node.zig").Node;
+const NodeUnion = @import("node.zig").Union;
+const DOMException = @import("exceptions.zig").DOMException;
+
+pub const Interfaces = .{
+    AbstractRange,
+    Range,
+};
+
+pub const AbstractRange = struct {
+    collapsed: bool,
+    end_node: *parser.Node,
+    end_offset: u32,
+    start_node: *parser.Node,
+    start_offset: u32,
+
+    pub fn updateCollapsed(self: *AbstractRange) void {
+        // TODO: Eventually, compare properly.
+        self.collapsed = false;
+    }
+
+    pub fn get_collapsed(self: *const AbstractRange) bool {
+        return self.collapsed;
+    }
+
+    pub fn get_endContainer(self: *const AbstractRange) !NodeUnion {
+        return Node.toInterface(self.end_node);
+    }
+
+    pub fn get_endOffset(self: *const AbstractRange) u32 {
+        return self.end_offset;
+    }
+
+    pub fn get_startContainer(self: *const AbstractRange) !NodeUnion {
+        return Node.toInterface(self.start_node);
+    }
+
+    pub fn get_startOffset(self: *const AbstractRange) u32 {
+        return self.start_offset;
+    }
+};
+
+pub const Range = struct {
+    pub const Exception = DOMException;
+    pub const prototype = *AbstractRange;
+
+    proto: AbstractRange,
+
+    pub const _START_TO_START = 0;
+    pub const _START_TO_END = 1;
+    pub const _END_TO_END = 2;
+    pub const _END_TO_START = 3;
+
+    // The Range() constructor returns a newly created Range object whose start
+    // and end is the global Document object.
+    // https://developer.mozilla.org/en-US/docs/Web/API/Range/Range
+    pub fn constructor(page: *Page) Range {
+        const proto: AbstractRange = .{
+            .collapsed = true,
+            .end_node = parser.documentHTMLToNode(page.window.document),
+            .end_offset = 0,
+            .start_node = parser.documentHTMLToNode(page.window.document),
+            .start_offset = 0,
+        };
+
+        return .{ .proto = proto };
+    }
+
+    pub fn _setStart(self: *Range, node: *parser.Node, offset_: i32) !void {
+        try ensureValidOffset(node, offset_);
+        const offset: u32 = @intCast(offset_);
+        const position = compare(node, offset, self.proto.start_node, self.proto.start_offset) catch |err| switch (err) {
+            error.WrongDocument => blk: {
+                // allow a node with a different root than the current, or
+                // a disconnected one. Treat it as if it's "after", so that
+                // we also update the end_offset and end_node.
+                break :blk 1;
+            },
+            else => return err,
+        };
+
+        if (position == 1) {
+            // if we're setting the node after the current start, the end must
+            // be set too.
+            self.proto.end_offset = offset;
+            self.proto.end_node = node;
+        }
+        self.proto.start_node = node;
+        self.proto.start_offset = offset;
+        self.proto.updateCollapsed();
+    }
+
+    pub fn _setStartBefore(self: *Range, node: *parser.Node) !void {
+        const parent, const index = try getParentAndIndex(node);
+        self.proto.start_node = parent;
+        self.proto.start_offset = index;
+    }
+
+    pub fn _setStartAfter(self: *Range, node: *parser.Node) !void {
+        const parent, const index = try getParentAndIndex(node);
+        self.proto.start_node = parent;
+        self.proto.start_offset = index + 1;
+    }
+
+    pub fn _setEnd(self: *Range, node: *parser.Node, offset_: i32) !void {
+        try ensureValidOffset(node, offset_);
+        const offset: u32 = @intCast(offset_);
+
+        const position = compare(node, offset, self.proto.start_node, self.proto.start_offset) catch |err| switch (err) {
+            error.WrongDocument => blk: {
+                // allow a node with a different root than the current, or
+                // a disconnected one. Treat it as if it's "before", so that
+                // we also update the end_offset and end_node.
+                break :blk -1;
+            },
+            else => return err,
+        };
+
+        if (position == -1) {
+            // if we're setting the node before the current start, the start
+            // must be set too.
+            self.proto.start_offset = offset;
+            self.proto.start_node = node;
+        }
+
+        self.proto.end_node = node;
+        self.proto.end_offset = offset;
+        self.proto.updateCollapsed();
+    }
+
+    pub fn _setEndBefore(self: *Range, node: *parser.Node) !void {
+        const parent, const index = try getParentAndIndex(node);
+        self.proto.end_node = parent;
+        self.proto.end_offset = index;
+    }
+
+    pub fn _setEndAfter(self: *Range, node: *parser.Node) !void {
+        const parent, const index = try getParentAndIndex(node);
+        self.proto.end_node = parent;
+        self.proto.end_offset = index + 1;
+    }
+
+    pub fn _createContextualFragment(_: *Range, fragment: []const u8, page: *Page) !*parser.DocumentFragment {
+        const document_html = page.window.document;
+        const document = parser.documentHTMLToDocument(document_html);
+        const doc_frag = try parser.documentParseFragmentFromStr(document, fragment);
+        return doc_frag;
+    }
+
+    pub fn _selectNodeContents(self: *Range, node: *parser.Node) !void {
+        self.proto.start_node = node;
+        self.proto.start_offset = 0;
+        self.proto.end_node = node;
+
+        // Set end_offset
+        switch (try parser.nodeType(node)) {
+            .text, .cdata_section, .comment, .processing_instruction => {
+                // For text-like nodes, end_offset should be the length of the text data
+                if (try parser.nodeValue(node)) |text_data| {
+                    self.proto.end_offset = @intCast(text_data.len);
+                } else {
+                    self.proto.end_offset = 0;
+                }
+            },
+            else => {
+                // For element and other nodes, end_offset is the number of children
+                const child_nodes = try parser.nodeGetChildNodes(node);
+                const child_count = try parser.nodeListLength(child_nodes);
+                self.proto.end_offset = @intCast(child_count);
+            },
+        }
+
+        self.proto.updateCollapsed();
+    }
+
+    // creates a copy
+    pub fn _cloneRange(self: *const Range) Range {
+        return .{
+            .proto = .{
+                .collapsed = self.proto.collapsed,
+                .end_node = self.proto.end_node,
+                .end_offset = self.proto.end_offset,
+                .start_node = self.proto.start_node,
+                .start_offset = self.proto.start_offset,
+            },
+        };
+    }
+
+    pub fn _comparePoint(self: *const Range, node: *parser.Node, offset_: i32) !i32 {
+        const start = self.proto.start_node;
+        if (try parser.nodeGetRootNode(start) != try parser.nodeGetRootNode(node)) {
+            // WPT really wants this error to be first. Later, when we check
+            // if the relative position is 'disconnected', it'll also catch this
+            // case, but WPT will complain because it sometimes also sends
+            // invalid offsets, and it wants WrongDocument to be raised.
+            return error.WrongDocument;
+        }
+
+        if (try parser.nodeType(node) == .document_type) {
+            return error.InvalidNodeType;
+        }
+
+        try ensureValidOffset(node, offset_);
+
+        const offset: u32 = @intCast(offset_);
+        if (try compare(node, offset, start, self.proto.start_offset) == -1) {
+            return -1;
+        }
+
+        if (try compare(node, offset, self.proto.end_node, self.proto.end_offset) == 1) {
+            return 1;
+        }
+
+        return 0;
+    }
+
+    pub fn _isPointInRange(self: *const Range, node: *parser.Node, offset_: i32) !bool {
+        return self._comparePoint(node, offset_) catch |err| switch (err) {
+            error.WrongDocument => return false,
+            else => return err,
+        } == 0;
+    }
+
+    pub fn _intersectsNode(self: *const Range, node: *parser.Node) !bool {
+        const start_root = try parser.nodeGetRootNode(self.proto.start_node);
+        const node_root = try parser.nodeGetRootNode(node);
+        if (start_root != node_root) {
+            return false;
+        }
+
+        const parent, const index = getParentAndIndex(node) catch |err| switch (err) {
+            error.InvalidNodeType => return true, // if node has no parent, we return true.
+            else => return err,
+        };
+
+        if (try compare(parent, index + 1, self.proto.start_node, self.proto.start_offset) != 1) {
+            // node isn't after start, can't intersect
+            return false;
+        }
+
+        if (try compare(parent, index, self.proto.end_node, self.proto.end_offset) != -1) {
+            // node isn't before end, can't intersect
+            return false;
+        }
+
+        return true;
+    }
+
+    pub fn _compareBoundaryPoints(self: *const Range, how: i32, other: *const Range) !i32 {
+        return switch (how) {
+            _START_TO_START => compare(self.proto.start_node, self.proto.start_offset, other.proto.start_node, other.proto.start_offset),
+            _START_TO_END => compare(self.proto.start_node, self.proto.start_offset, other.proto.end_node, other.proto.end_offset),
+            _END_TO_END => compare(self.proto.end_node, self.proto.end_offset, other.proto.end_node, other.proto.end_offset),
+            _END_TO_START => compare(self.proto.end_node, self.proto.end_offset, other.proto.start_node, other.proto.start_offset),
+            else => error.NotSupported, // this is the correct DOM Exception to return
+        };
+    }
+
+    // The Range.detach() method does nothing. It used to disable the Range
+    // object and enable the browser to release associated resources. The
+    // method has been kept for compatibility.
+    // https://developer.mozilla.org/en-US/docs/Web/API/Range/detach
+    pub fn _detach(_: *Range) void {}
+};
+
+fn ensureValidOffset(node: *parser.Node, offset: i32) !void {
+    if (offset < 0) {
+        return error.IndexSize;
+    }
+
+    // not >= because 0 seems to represent the node itself.
+    if (offset > try nodeLength(node)) {
+        return error.IndexSize;
+    }
+}
+
+fn nodeLength(node: *parser.Node) !usize {
+    switch (try isTextual(node)) {
+        true => return ((try parser.nodeTextContent(node)) orelse "").len,
+        false => {
+            const children = try parser.nodeGetChildNodes(node);
+            return @intCast(try parser.nodeListLength(children));
+        },
+    }
+}
+
+fn isTextual(node: *parser.Node) !bool {
+    return switch (try parser.nodeType(node)) {
+        .text, .comment, .cdata_section => true,
+        else => false,
+    };
+}
+
+fn getParentAndIndex(child: *parser.Node) !struct { *parser.Node, u32 } {
+    const parent = (try parser.nodeParentNode(child)) orelse return error.InvalidNodeType;
+    const children = try parser.nodeGetChildNodes(parent);
+    const ln = try parser.nodeListLength(children);
+    var i: u32 = 0;
+    while (i < ln) {
+        defer i += 1;
+        const c = try parser.nodeListItem(children, i) orelse continue;
+        if (c == child) {
+            return .{ parent, i };
+        }
+    }
+
+    // should not be possible to reach this point
+    return error.InvalidNodeType;
+}
+
+// implementation is largely copied from the WPT helper called getPosition in
+// the common.js of the dom folder.
+fn compare(node_a: *parser.Node, offset_a: u32, node_b: *parser.Node, offset_b: u32) !i32 {
+    if (node_a == node_b) {
+        // This is a simple and common case, where the two nodes are the same
+        // We just need to compare their offsets
+        if (offset_a == offset_b) {
+            return 0;
+        }
+        return if (offset_a < offset_b) -1 else 1;
+    }
+
+    // We're probably comparing two different nodes. "Probably", because the
+    // above case on considered the offset if the two nodes were the same
+    // as-is. They could still be the same here, if we first consider the
+    // offset.
+    const position = try Node._compareDocumentPosition(node_b, node_a);
+    if (position & @intFromEnum(parser.DocumentPosition.disconnected) == @intFromEnum(parser.DocumentPosition.disconnected)) {
+        return error.WrongDocument;
+    }
+
+    if (position & @intFromEnum(parser.DocumentPosition.following) == @intFromEnum(parser.DocumentPosition.following)) {
+        return switch (try compare(node_b, offset_b, node_a, offset_a)) {
+            -1 => 1,
+            1 => -1,
+            else => unreachable,
+        };
+    }
+
+    if (position & @intFromEnum(parser.DocumentPosition.contains) == @intFromEnum(parser.DocumentPosition.contains)) {
+        // node_a contains node_b
+        var child = node_b;
+        while (try parser.nodeParentNode(child)) |parent| {
+            if (parent == node_a) {
+                // child.parentNode == node_a
+                break;
+            }
+            child = parent;
+        } else {
+            // this should not happen, because  Node._compareDocumentPosition
+            // has told us that node_a contains node_b, so one of node_b's
+            // parent's MUST be node_a. But somehow we do end up here sometimes.
+            return -1;
+        }
+
+        const child_parent, const child_index = try getParentAndIndex(child);
+        std.debug.assert(node_a == child_parent);
+        return if (child_index < offset_a) -1 else 1;
+    }
+
+    return -1;
+}
+
+const testing = @import("../../testing.zig");
+test "Browser.Range" {
+    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
+    defer runner.deinit();
+
+    try runner.testCases(&.{
+        // Test Range constructor
+        .{ "let range = new Range()", "undefined" },
+        .{ "range instanceof Range", "true" },
+        .{ "range instanceof AbstractRange", "true" },
+
+        // Test initial state - collapsed range
+        .{ "range.collapsed", "true" },
+        .{ "range.startOffset", "0" },
+        .{ "range.endOffset", "0" },
+        .{ "range.startContainer instanceof HTMLDocument", "true" },
+        .{ "range.endContainer instanceof HTMLDocument", "true" },
+
+        // Test document.createRange()
+        .{ "let docRange = document.createRange()", "undefined" },
+        .{ "docRange instanceof Range", "true" },
+        .{ "docRange.collapsed", "true" },
+    }, .{});
+
+    try runner.testCases(&.{
+        .{ "const container = document.getElementById('content');", null },
+
+        // Test text range
+        .{ "const commentNode = container.childNodes[7];", null },
+        .{ "commentNode.nodeValue", "comment" },
+        .{ "const textRange = document.createRange();", null },
+        .{ "textRange.selectNodeContents(commentNode)", "undefined" },
+        .{ "textRange.startOffset", "0" },
+        .{ "textRange.endOffset", "7" }, // length of `comment`
+
+        // Test Node range
+        .{ "const nodeRange = document.createRange();", null },
+        .{ "nodeRange.selectNodeContents(container)", "undefined" },
+        .{ "nodeRange.startOffset", "0" },
+        .{ "nodeRange.endOffset", "9" }, // length of container.childNodes
+    }, .{});
+}

src/browser/dom/resize_observer.zig

@@ -0,0 +1,54 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const Env = @import("../env.zig").Env;
+const parser = @import("../netsurf.zig");
+
+pub const Interfaces = .{
+    ResizeObserver,
+};
+
+// WEB IDL https://drafts.csswg.org/resize-observer/#resize-observer-interface
+pub const ResizeObserver = struct {
+    pub fn constructor(cbk: Env.Function) ResizeObserver {
+        _ = cbk;
+        return .{};
+    }
+
+    pub fn _observe(self: *const ResizeObserver, element: *parser.Element, options_: ?Options) void {
+        _ = self;
+        _ = element;
+        _ = options_;
+        return;
+    }
+
+    pub fn _unobserve(self: *const ResizeObserver, element: *parser.Element) void {
+        _ = self;
+        _ = element;
+        return;
+    }
+
+    // TODO
+    pub fn _disconnect(self: *ResizeObserver) void {
+        _ = self;
+    }
+};
+
+const Options = struct {
+    box: []const u8,
+};

src/browser/dom/shadow_root.zig

@@ -0,0 +1,155 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+const dump = @import("../dump.zig");
+const parser = @import("../netsurf.zig");
+
+const Env = @import("../env.zig").Env;
+const Page = @import("../page.zig").Page;
+const Node = @import("node.zig").Node;
+const Element = @import("element.zig").Element;
+const ElementUnion = @import("element.zig").Union;
+
+// WEB IDL https://dom.spec.whatwg.org/#interface-shadowroot
+pub const ShadowRoot = struct {
+    pub const prototype = *parser.DocumentFragment;
+    pub const subtype = .node;
+
+    mode: Mode,
+    host: *parser.Element,
+    proto: *parser.DocumentFragment,
+    adopted_style_sheets: ?Env.JsObject = null,
+
+    pub const Mode = enum {
+        open,
+        closed,
+    };
+
+    pub fn get_host(self: *const ShadowRoot) !ElementUnion {
+        return Element.toInterface(self.host);
+    }
+
+    pub fn get_adoptedStyleSheets(self: *ShadowRoot, page: *Page) !Env.JsObject {
+        if (self.adopted_style_sheets) |obj| {
+            return obj;
+        }
+
+        const obj = try page.main_context.newArray(0).persist();
+        self.adopted_style_sheets = obj;
+        return obj;
+    }
+
+    pub fn set_adoptedStyleSheets(self: *ShadowRoot, sheets: Env.JsObject) !void {
+        self.adopted_style_sheets = try sheets.persist();
+    }
+
+    pub fn get_innerHTML(self: *ShadowRoot, page: *Page) ![]const u8 {
+        var aw = std.Io.Writer.Allocating.init(page.call_arena);
+        try dump.writeChildren(parser.documentFragmentToNode(self.proto), .{}, &aw.writer);
+        return aw.written();
+    }
+
+    pub fn set_innerHTML(self: *ShadowRoot, str_: ?[]const u8) !void {
+        const sr_doc = parser.documentFragmentToNode(self.proto);
+        const doc = try parser.nodeOwnerDocument(sr_doc) orelse return parser.DOMError.WrongDocument;
+        try Node.removeChildren(sr_doc);
+        const str = str_ orelse return;
+
+        const fragment = try parser.documentParseFragmentFromStr(doc, str);
+        const fragment_node = parser.documentFragmentToNode(fragment);
+
+        // Element.set_innerHTML also has some weirdness here. It isn't clear
+        // what should and shouldn't be set. Whatever string you pass to libdom,
+        // it always creates a full HTML document, with an html, head and body
+        // element.
+        // For ShadowRoot, it appears the only the children within the body should
+        // be set.
+        const html = try parser.nodeFirstChild(fragment_node) orelse return;
+        const head = try parser.nodeFirstChild(html) orelse return;
+        const body = try parser.nodeNextSibling(head) orelse return;
+
+        const children = try parser.nodeGetChildNodes(body);
+        const ln = try parser.nodeListLength(children);
+        for (0..ln) |_| {
+            // always index 0, because nodeAppendChild moves the node out of
+            // the nodeList and into the new tree
+            const child = try parser.nodeListItem(children, 0) orelse continue;
+            _ = try parser.nodeAppendChild(sr_doc, child);
+        }
+    }
+};
+
+const testing = @import("../../testing.zig");
+test "Browser.DOM.ShadowRoot" {
+    defer testing.reset();
+
+    var runner = try testing.jsRunner(testing.tracking_allocator, .{ .html = 
+        \\ <div id=conflict>nope</div>
+    });
+    defer runner.deinit();
+
+    try runner.testCases(&.{
+        .{ "const div1 = document.createElement('div');", null },
+        .{ "let sr1 = div1.attachShadow({mode: 'open'})", null },
+        .{ "sr1.host == div1", "true" },
+        .{ "div1.attachShadow({mode: 'open'}) == sr1", "true" },
+        .{ "div1.shadowRoot == sr1", "true" },
+
+        .{ "try { div1.attachShadow({mode: 'closed'}) } catch (e) { e }", "Error: NotSupportedError" },
+
+        .{ " sr1.append(document.createElement('div'))", null },
+        .{ " sr1.append(document.createElement('span'))", null },
+        .{ "sr1.childElementCount", "2" },
+        // re-attaching clears it
+        .{ "div1.attachShadow({mode: 'open'}) == sr1", "true" },
+        .{ "sr1.childElementCount", "0" },
+    }, .{});
+
+    try runner.testCases(&.{
+        .{ "const div2 = document.createElement('di2');", null },
+        .{ "let sr2 = div2.attachShadow({mode: 'closed'})", null },
+        .{ "sr2.host == div2", "true" },
+        .{ "div2.shadowRoot", "null" }, // null when attached with 'closed'
+    }, .{});
+
+    try runner.testCases(&.{
+        .{ "sr2.getElementById('conflict')", "null" },
+        .{ "const n1 = document.createElement('div')", null },
+        .{ "n1.id = 'conflict'", null },
+        .{ "sr2.append(n1)", null },
+        .{ "sr2.getElementById('conflict') == n1", "true" },
+    }, .{});
+
+    try runner.testCases(&.{
+        .{ "const acss = sr2.adoptedStyleSheets", null },
+        .{ "acss.length", "0" },
+        .{ "acss.push(new CSSStyleSheet())", null },
+        .{ "sr2.adoptedStyleSheets.length", "1" },
+    }, .{});
+
+    try runner.testCases(&.{
+        .{ "sr1.innerHTML = '<p>hello</p>'", null },
+        .{ "sr1.innerHTML", "<p>hello</p>" },
+        .{ "sr1.querySelector('*')", "[object HTMLParagraphElement]" },
+
+        .{ "sr1.innerHTML = null", null },
+        .{ "sr1.innerHTML", "" },
+        .{ "sr1.querySelector('*')", "null" },
+    }, .{});
+}

src/browser/dom/tree_walker.zig

@@ -19,23 +19,31 @@
 const std = @import("std");
 const parser = @import("../netsurf.zig");
 
-const NodeFilter = @import("node_filter.zig").NodeFilter;
+const NodeFilter = @import("node_filter.zig");
 const Env = @import("../env.zig").Env;
 const Page = @import("../page.zig").Page;
+const Node = @import("node.zig").Node;
+const NodeUnion = @import("node.zig").Union;
 
 // https://developer.mozilla.org/en-US/docs/Web/API/TreeWalker
 pub const TreeWalker = struct {
     root: *parser.Node,
     current_node: *parser.Node,
     what_to_show: u32,
-    filter: ?Env.Function,
+    filter: ?TreeWalkerOpts,
+    filter_func: ?Env.Function,
+
+    // One of the few cases where null and undefined resolve to different default.
+    // We need the raw JsObject so that we can probe the tri state:
+    // null, undefined or i32.
+    pub const WhatToShow = Env.JsObject;
 
     pub const TreeWalkerOpts = union(enum) {
         function: Env.Function,
         object: struct { acceptNode: Env.Function },
     };
 
-    pub fn init(node: *parser.Node, what_to_show: ?u32, filter: ?TreeWalkerOpts) !TreeWalker {
+    pub fn init(node: *parser.Node, what_to_show_: ?WhatToShow, filter: ?TreeWalkerOpts) !TreeWalker {
         var filter_func: ?Env.Function = null;
 
         if (filter) |f| {
@@ -45,61 +53,39 @@ pub const TreeWalker = struct {
             };
         }
 
+        var what_to_show: u32 = undefined;
+        if (what_to_show_) |wts| {
+            switch (try wts.triState(TreeWalker, "what_to_show", u32)) {
+                .null => what_to_show = 0,
+                .undefined => what_to_show = NodeFilter.NodeFilter._SHOW_ALL,
+                .value => |v| what_to_show = v,
+            }
+        } else {
+            what_to_show = NodeFilter.NodeFilter._SHOW_ALL;
+        }
+
         return .{
             .root = node,
             .current_node = node,
-            .what_to_show = what_to_show orelse NodeFilter._SHOW_ALL,
-            .filter = filter_func,
+            .what_to_show = what_to_show,
+            .filter = filter,
+            .filter_func = filter_func,
         };
     }
 
-    const VerifyResult = enum { accept, skip, reject };
-
-    fn verify(self: *const TreeWalker, node: *parser.Node) !VerifyResult {
-        const node_type = try parser.nodeType(node);
-        const what_to_show = self.what_to_show;
-
-        // Verify that we can show this node type.
-        if (!switch (node_type) {
-            .attribute => what_to_show & NodeFilter._SHOW_ATTRIBUTE != 0,
-            .cdata_section => what_to_show & NodeFilter._SHOW_CDATA_SECTION != 0,
-            .comment => what_to_show & NodeFilter._SHOW_COMMENT != 0,
-            .document => what_to_show & NodeFilter._SHOW_DOCUMENT != 0,
-            .document_fragment => what_to_show & NodeFilter._SHOW_DOCUMENT_FRAGMENT != 0,
-            .document_type => what_to_show & NodeFilter._SHOW_DOCUMENT_TYPE != 0,
-            .element => what_to_show & NodeFilter._SHOW_ELEMENT != 0,
-            .entity => what_to_show & NodeFilter._SHOW_ENTITY != 0,
-            .entity_reference => what_to_show & NodeFilter._SHOW_ENTITY_REFERENCE != 0,
-            .notation => what_to_show & NodeFilter._SHOW_NOTATION != 0,
-            .processing_instruction => what_to_show & NodeFilter._SHOW_PROCESSING_INSTRUCTION != 0,
-            .text => what_to_show & NodeFilter._SHOW_TEXT != 0,
-        }) return .reject;
-
-        // Verify that we aren't filtering it out.
-        if (self.filter) |f| {
-            const filter = try f.call(u32, .{node});
-            return switch (filter) {
-                NodeFilter._FILTER_ACCEPT => .accept,
-                NodeFilter._FILTER_REJECT => .reject,
-                NodeFilter._FILTER_SKIP => .skip,
-                else => .reject,
-            };
-        } else return .accept;
+    pub fn get_root(self: *TreeWalker) !NodeUnion {
+        return try Node.toInterface(self.root);
     }
 
-    pub fn get_root(self: *TreeWalker) *parser.Node {
-        return self.root;
-    }
-
-    pub fn get_currentNode(self: *TreeWalker) *parser.Node {
-        return self.current_node;
+    pub fn get_currentNode(self: *TreeWalker) !NodeUnion {
+        return try Node.toInterface(self.current_node);
     }
 
     pub fn get_whatToShow(self: *TreeWalker) u32 {
         return self.what_to_show;
     }
 
-    pub fn get_filter(self: *TreeWalker) ?Env.Function {
+    pub fn get_filter(self: *TreeWalker) ?TreeWalkerOpts {
         return self.filter;
     }
 
@@ -115,7 +101,7 @@ pub const TreeWalker = struct {
             const index: u32 = @intCast(i);
             const child = (try parser.nodeListItem(children, index)) orelse return null;
 
-            switch (try self.verify(child)) {
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, child)) {
                 .accept => return child,
                 .reject => continue,
                 .skip => if (try self.firstChild(child)) |gchild| return gchild,
@@ -134,7 +120,7 @@ pub const TreeWalker = struct {
             index -= 1;
             const child = (try parser.nodeListItem(children, index)) orelse return null;
 
-            switch (try self.verify(child)) {
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, child)) {
                 .accept => return child,
                 .reject => continue,
                 .skip => if (try self.lastChild(child)) |gchild| return gchild,
@@ -150,7 +136,7 @@ pub const TreeWalker = struct {
         while (true) {
             current = (try parser.nodeNextSibling(current)) orelse return null;
 
-            switch (try self.verify(current)) {
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, current)) {
                 .accept => return current,
                 .skip, .reject => continue,
             }
@@ -165,7 +151,7 @@ pub const TreeWalker = struct {
         while (true) {
             current = (try parser.nodePreviousSibling(current)) orelse return null;
 
-            switch (try self.verify(current)) {
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, current)) {
                 .accept => return current,
                 .skip, .reject => continue,
             }
@@ -182,42 +168,42 @@ pub const TreeWalker = struct {
             if (current == self.root) return null;
             current = (try parser.nodeParentNode(current)) orelse return null;
 
-            switch (try self.verify(current)) {
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, current)) {
                 .accept => return current,
                 .reject, .skip => continue,
             }
         }
     }
 
-    pub fn _firstChild(self: *TreeWalker) !?*parser.Node {
+    pub fn _firstChild(self: *TreeWalker) !?NodeUnion {
         if (try self.firstChild(self.current_node)) |child| {
             self.current_node = child;
-            return child;
+            return try Node.toInterface(child);
         }
 
         return null;
     }
 
-    pub fn _lastChild(self: *TreeWalker) !?*parser.Node {
+    pub fn _lastChild(self: *TreeWalker) !?NodeUnion {
         if (try self.lastChild(self.current_node)) |child| {
             self.current_node = child;
-            return child;
+            return try Node.toInterface(child);
         }
 
         return null;
     }
 
-    pub fn _nextNode(self: *TreeWalker) !?*parser.Node {
+    pub fn _nextNode(self: *TreeWalker) !?NodeUnion {
         if (try self.firstChild(self.current_node)) |child| {
             self.current_node = child;
-            return child;
+            return try Node.toInterface(child);
         }
 
         var current = self.current_node;
         while (current != self.root) {
             if (try self.nextSibling(current)) |sibling| {
                 self.current_node = sibling;
-                return sibling;
+                return try Node.toInterface(sibling);
             }
 
             current = (try parser.nodeParentNode(current)) orelse break;
@@ -226,47 +212,49 @@ pub const TreeWalker = struct {
         return null;
     }
 
-    pub fn _nextSibling(self: *TreeWalker) !?*parser.Node {
+    pub fn _nextSibling(self: *TreeWalker) !?NodeUnion {
         if (try self.nextSibling(self.current_node)) |sibling| {
             self.current_node = sibling;
-            return sibling;
+            return try Node.toInterface(sibling);
         }
 
         return null;
     }
 
-    pub fn _parentNode(self: *TreeWalker) !?*parser.Node {
+    pub fn _parentNode(self: *TreeWalker) !?NodeUnion {
         if (try self.parentNode(self.current_node)) |parent| {
             self.current_node = parent;
-            return parent;
+            return try Node.toInterface(parent);
         }
 
         return null;
     }
 
-    pub fn _previousNode(self: *TreeWalker) !?*parser.Node {
+    pub fn _previousNode(self: *TreeWalker) !?NodeUnion {
+        if (self.current_node == self.root) return null;
+
         var current = self.current_node;
         while (try parser.nodePreviousSibling(current)) |previous| {
             current = previous;
 
-            switch (try self.verify(current)) {
+            switch (try NodeFilter.verify(self.what_to_show, self.filter_func, current)) {
                 .accept => {
                     // Get last child if it has one.
                     if (try self.lastChild(current)) |child| {
                         self.current_node = child;
-                        return child;
+                        return try Node.toInterface(child);
                     }
 
                     // Otherwise, this node is our previous one.
                     self.current_node = current;
-                    return current;
+                    return try Node.toInterface(current);
                 },
                 .reject => continue,
                 .skip => {
                     // Get last child if it has one.
                     if (try self.lastChild(current)) |child| {
                         self.current_node = child;
-                        return child;
+                        return try Node.toInterface(child);
                     }
                 },
             }
@@ -275,17 +263,17 @@ pub const TreeWalker = struct {
         if (current != self.root) {
             if (try self.parentNode(current)) |parent| {
                 self.current_node = parent;
-                return parent;
+                return try Node.toInterface(parent);
             }
         }
 
         return null;
     }
 
-    pub fn _previousSibling(self: *TreeWalker) !?*parser.Node {
+    pub fn _previousSibling(self: *TreeWalker) !?NodeUnion {
         if (try self.previousSibling(self.current_node)) |sibling| {
             self.current_node = sibling;
-            return sibling;
+            return try Node.toInterface(sibling);
         }
 
         return null;

src/browser/dump.zig

@@ -19,17 +19,25 @@
 const std = @import("std");
 
 const parser = @import("netsurf.zig");
+const Page = @import("page.zig").Page;
 const Walker = @import("dom/walker.zig").WalkerChildren;
 
+pub const Opts = struct {
+    // set to include element shadowroots in the dump
+    page: ?*const Page = null,
+
+    exclude_scripts: bool = false,
+};
+
 // writer must be a std.io.Writer
-pub fn writeHTML(doc: *parser.Document, writer: anytype) !void {
+pub fn writeHTML(doc: *parser.Document, opts: Opts, writer: *std.Io.Writer) !void {
     try writer.writeAll("<!DOCTYPE html>\n");
-    try writeChildren(parser.documentToNode(doc), writer);
+    try writeChildren(parser.documentToNode(doc), opts, writer);
     try writer.writeAll("\n");
 }
 
 // Spec: https://www.w3.org/TR/xml/#sec-prolog-dtd
-pub fn writeDocType(doc_type: *parser.DocumentType, writer: anytype) !void {
+pub fn writeDocType(doc_type: *parser.DocumentType, writer: *std.Io.Writer) !void {
     try writer.writeAll("<!DOCTYPE ");
     try writer.writeAll(try parser.documentTypeGetName(doc_type));
 
@@ -54,10 +62,15 @@ pub fn writeDocType(doc_type: *parser.DocumentType, writer: anytype) !void {
     try writer.writeAll(">");
 }
 
-pub fn writeNode(node: *parser.Node, writer: anytype) anyerror!void {
+pub fn writeNode(node: *parser.Node, opts: Opts, writer: *std.Io.Writer) anyerror!void {
     switch (try parser.nodeType(node)) {
         .element => {
             // open the tag
+            const tag_type = try parser.nodeHTMLGetTagType(node) orelse .undef;
+            if (opts.exclude_scripts and try isScriptOrRelated(tag_type, node)) {
+                return;
+            }
+
             const tag = try parser.nodeLocalName(node);
             try writer.writeAll("<");
             try writer.writeAll(tag);
@@ -79,12 +92,24 @@ pub fn writeNode(node: *parser.Node, writer: anytype) anyerror!void {
 
             try writer.writeAll(">");
 
+            if (opts.page) |page| {
+                if (page.getNodeState(node)) |state| {
+                    if (state.shadow_root) |sr| {
+                        try writeChildren(@ptrCast(@alignCast(sr.proto)), opts, writer);
+                    }
+                }
+            }
+
             // void elements can't have any content.
             if (try isVoid(parser.nodeToElement(node))) return;
 
-            // write the children
-            // TODO avoid recursion
-            try writeChildren(node, writer);
+            if (tag_type == .script) {
+                try writer.writeAll(try parser.nodeTextContent(node) orelse "");
+            } else {
+                // write the children
+                // TODO avoid recursion
+                try writeChildren(node, opts, writer);
+            }
 
             // close the tag
             try writer.writeAll("</");
@@ -125,19 +150,38 @@ pub fn writeNode(node: *parser.Node, writer: anytype) anyerror!void {
 }
 
 // writer must be a std.io.Writer
-pub fn writeChildren(root: *parser.Node, writer: anytype) !void {
+pub fn writeChildren(root: *parser.Node, opts: Opts, writer: *std.Io.Writer) !void {
     const walker = Walker{};
     var next: ?*parser.Node = null;
     while (true) {
         next = try walker.get_next(root, next) orelse break;
-        try writeNode(next.?, writer);
+        try writeNode(next.?, opts, writer);
     }
 }
 
+// When `exclude_scripts` is passed to dump, we don't include <script> tags.
+// We also want to omit <link rel=preload as=ascript>
+fn isScriptOrRelated(tag_type: parser.Tag, node: *parser.Node) !bool {
+    if (tag_type == .script) {
+        return true;
+    }
+    if (tag_type == .link) {
+        const el = parser.nodeToElement(node);
+        const as = try parser.elementGetAttribute(el, "as") orelse return false;
+        if (!std.ascii.eqlIgnoreCase(as, "script")) {
+            return false;
+        }
+
+        const rel = try parser.elementGetAttribute(el, "rel") orelse return false;
+        return std.ascii.eqlIgnoreCase(rel, "preload");
+    }
+    return false;
+}
+
 // area, base, br, col, embed, hr, img, input, link, meta, source, track, wbr
 // https://html.spec.whatwg.org/#void-elements
 fn isVoid(elem: *parser.Element) !bool {
-    const tag = try parser.elementHTMLGetTagType(@as(*parser.ElementHTML, @ptrCast(elem)));
+    const tag = try parser.elementTag(elem);
     return switch (tag) {
         .area, .base, .br, .col, .embed, .hr, .img, .input, .link => true,
         .meta, .source, .track, .wbr => true,
@@ -211,6 +255,11 @@ test "dump.writeHTML" {
         \\</head><body>9000</body></html>
         \\
     , "<html><title>It's over what?</title><meta name=a value=\"b\">\n<body>9000");
+
+    try testWriteHTML(
+        "<p>hi</p><script>alert(power > 9000)</script>",
+        "<p>hi</p><script>alert(power > 9000)</script>",
+    );
 }
 
 fn testWriteHTML(comptime expected_body: []const u8, src: []const u8) !void {
@@ -222,13 +271,13 @@ fn testWriteHTML(comptime expected_body: []const u8, src: []const u8) !void {
 }
 
 fn testWriteFullHTML(comptime expected: []const u8, src: []const u8) !void {
-    var buf = std.ArrayListUnmanaged(u8){};
-    defer buf.deinit(testing.allocator);
+    var aw = std.Io.Writer.Allocating.init(testing.allocator);
+    defer aw.deinit();
 
     const doc_html = try parser.documentHTMLParseFromStr(src);
     defer parser.documentHTMLClose(doc_html) catch {};
 
     const doc = parser.documentHTMLToDocument(doc_html);
-    try writeHTML(doc, buf.writer(testing.allocator));
-    try testing.expectEqualStrings(expected, buf.items);
+    try writeHTML(doc, .{}, &aw.writer);
+    try testing.expectEqualStrings(expected, aw.written());
 }

src/browser/encoding/TextDecoder.zig

@@ -0,0 +1,84 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+const log = @import("../../log.zig");
+
+const Env = @import("../env.zig").Env;
+
+// https://encoding.spec.whatwg.org/#interface-textdecoder
+const TextDecoder = @This();
+
+const SupportedLabels = enum {
+    utf8,
+    @"utf-8",
+    @"unicode-1-1-utf-8",
+};
+
+const Options = struct {
+    fatal: bool = false,
+    ignoreBOM: bool = false,
+};
+
+fatal: bool,
+ignore_bom: bool,
+
+pub fn constructor(label_: ?[]const u8, opts_: ?Options) !TextDecoder {
+    if (label_) |l| {
+        _ = std.meta.stringToEnum(SupportedLabels, l) orelse {
+            log.warn(.web_api, "not implemented", .{ .feature = "TextDecoder label", .label = l });
+            return error.NotImplemented;
+        };
+    }
+    const opts = opts_ orelse Options{};
+    return .{
+        .fatal = opts.fatal,
+        .ignore_bom = opts.ignoreBOM,
+    };
+}
+
+pub fn get_encoding(_: *const TextDecoder) []const u8 {
+    return "utf-8";
+}
+
+pub fn get_ignoreBOM(self: *const TextDecoder) bool {
+    return self.ignore_bom;
+}
+
+pub fn get_fatal(self: *const TextDecoder) bool {
+    return self.fatal;
+}
+
+// TODO: Should accept an ArrayBuffer, TypedArray or DataView
+// js.zig will currently only map a TypedArray to our []const u8.
+pub fn _decode(self: *const TextDecoder, v: []const u8) ![]const u8 {
+    if (self.fatal and !std.unicode.utf8ValidateSlice(v)) {
+        return error.InvalidUtf8;
+    }
+
+    if (self.ignore_bom == false and std.mem.startsWith(u8, v, &.{ 0xEF, 0xBB, 0xBF })) {
+        return v[3..];
+    }
+
+    return v;
+}
+
+const testing = @import("../../testing.zig");
+test "Browser: Encoding.TextDecoder" {
+    try testing.htmlRunner("encoding/decoder.html");
+}

src/browser/encoding/TextEncoder.zig

@@ -0,0 +1,48 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const Env = @import("../env.zig").Env;
+
+// https://encoding.spec.whatwg.org/#interface-textencoder
+const TextEncoder = @This();
+
+pub fn constructor() !TextEncoder {
+    return .{};
+}
+
+pub fn get_encoding(_: *const TextEncoder) []const u8 {
+    return "utf-8";
+}
+
+pub fn _encode(_: *const TextEncoder, v: []const u8) !Env.TypedArray(u8) {
+    // Ensure the input is a valid utf-8
+    // It seems chrome accepts invalid utf-8 sequence.
+    //
+    if (!std.unicode.utf8ValidateSlice(v)) {
+        return error.InvalidUtf8;
+    }
+
+    return .{ .values = v };
+}
+
+const testing = @import("../../testing.zig");
+test "Browser: Encoding.TextEncoder" {
+    try testing.htmlRunner("encoding/encoder.html");
+}

src/browser/encoding/encoding.zig

@@ -1,4 +1,4 @@
-// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
 //
 // Francis Bouvier <francis@lightpanda.io>
 // Pierre Tachoire <pierre@lightpanda.io>
@@ -16,8 +16,7 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-const CustomElementRegistry = @import("custom_element_registry.zig").CustomElementRegistry;
-
 pub const Interfaces = .{
-    CustomElementRegistry,
+    @import("TextDecoder.zig"),
+    @import("TextEncoder.zig"),
 };

src/browser/encoding/text_encoder.zig

@@ -1,64 +0,0 @@
-// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
-//
-// Francis Bouvier <francis@lightpanda.io>
-// Pierre Tachoire <pierre@lightpanda.io>
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Affero General Public License as
-// published by the Free Software Foundation, either version 3 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Affero General Public License for more details.
-//
-// You should have received a copy of the GNU Affero General Public License
-// along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-const std = @import("std");
-
-const Env = @import("../env.zig").Env;
-
-pub const Interfaces = .{
-    TextEncoder,
-};
-
-// https://encoding.spec.whatwg.org/#interface-textencoder
-pub const TextEncoder = struct {
-    pub fn constructor() !TextEncoder {
-        return .{};
-    }
-
-    pub fn get_encoding(_: *const TextEncoder) []const u8 {
-        return "utf-8";
-    }
-
-    pub fn _encode(_: *const TextEncoder, v: []const u8) !Env.TypedArray(u8) {
-        // Ensure the input is a valid utf-8
-        // It seems chrome accepts invalid utf-8 sequence.
-        //
-        if (!std.unicode.utf8ValidateSlice(v)) {
-            return error.InvalidUtf8;
-        }
-
-        return .{ .values = v };
-    }
-};
-
-const testing = @import("../../testing.zig");
-test "Browser.Encoding.TextEncoder" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "var encoder = new TextEncoder();", "undefined" },
-        .{ "encoder.encoding;", "utf-8" },
-        .{ "encoder.encode('€');", "226,130,172" },
-
-        // Invalid utf-8 sequence.
-        // Result with chrome:
-        // .{ "encoder.encode(new Uint8Array([0xE2,0x28,0xA1]))", "50,50,54,44,52,48,44,49,54,49" },
-        .{ "try {encoder.encode(new Uint8Array([0xE2,0x28,0xA1])) } catch (e) { e };", "Error: InvalidUtf8" },
-    }, .{});
-}

src/browser/env.zig

@@ -22,9 +22,11 @@ const WebApis = struct {
     pub const Interfaces = generate.Tuple(.{
         @import("crypto/crypto.zig").Crypto,
         @import("console/console.zig").Console,
+        @import("css/css.zig").Interfaces,
         @import("cssom/cssom.zig").Interfaces,
         @import("dom/dom.zig").Interfaces,
-        @import("encoding/text_encoder.zig").Interfaces,
+        @import("dom/shadow_root.zig").ShadowRoot,
+        @import("encoding/encoding.zig").Interfaces,
         @import("events/event.zig").Interfaces,
         @import("html/html.zig").Interfaces,
         @import("iterator/iterator.zig").Interfaces,
@@ -32,13 +34,16 @@ const WebApis = struct {
         @import("url/url.zig").Interfaces,
         @import("xhr/xhr.zig").Interfaces,
         @import("xhr/form_data.zig").Interfaces,
+        @import("xhr/File.zig"),
         @import("xmlserializer/xmlserializer.zig").Interfaces,
-        @import("webcomponents/webcomponents.zig").Interfaces,
     });
 };
 
 pub const JsThis = Env.JsThis;
 pub const JsObject = Env.JsObject;
 pub const Function = Env.Function;
+pub const Promise = Env.Promise;
+pub const PromiseResolver = Env.PromiseResolver;
+
 pub const Env = js.Env(*Page, WebApis);
 pub const Global = @import("html/window.zig").Window;

src/browser/events/custom_event.zig

@@ -19,6 +19,7 @@
 const parser = @import("../netsurf.zig");
 const Event = @import("event.zig").Event;
 const JsObject = @import("../env.zig").JsObject;
+const netsurf = @import("../netsurf.zig");
 
 // https://dom.spec.whatwg.org/#interface-customevent
 pub const CustomEvent = struct {
@@ -55,26 +56,30 @@ pub const CustomEvent = struct {
     pub fn get_detail(self: *CustomEvent) ?JsObject {
         return self.detail;
     }
+
+    // Initializes an already created `CustomEvent`.
+    // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/initCustomEvent
+    pub fn _initCustomEvent(
+        self: *CustomEvent,
+        event_type: []const u8,
+        can_bubble: bool,
+        cancelable: bool,
+        maybe_detail: ?JsObject,
+    ) !void {
+        // This function can only be called after the constructor has called.
+        // So we assume proto is initialized already by constructor.
+        self.proto.type = try netsurf.strFromData(event_type);
+        self.proto.bubble = can_bubble;
+        self.proto.cancelable = cancelable;
+        self.proto.is_initialised = true;
+        // Detail is stored separately.
+        if (maybe_detail) |detail| {
+            self.detail = try detail.persist();
+        }
+    }
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.CustomEvent" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let capture = null", "undefined" },
-        .{ "const el = document.createElement('div');", "undefined" },
-        .{ "el.addEventListener('c1', (e) => { capture = 'c1-' + new String(e.detail)})", "undefined" },
-        .{ "el.addEventListener('c2', (e) => { capture = 'c2-' + new String(e.detail.over)})", "undefined" },
-
-        .{ "el.dispatchEvent(new CustomEvent('c1'));", "true" },
-        .{ "capture", "c1-null" },
-
-        .{ "el.dispatchEvent(new CustomEvent('c1', {detail: '123'}));", "true" },
-        .{ "capture", "c1-123" },
-
-        .{ "el.dispatchEvent(new CustomEvent('c2', {detail: {over: 9000}}));", "true" },
-        .{ "capture", "c2-9000" },
-    }, .{});
+test "Browser: Events.Custom" {
+    try testing.htmlRunner("events/custom.html");
 }

src/browser/events/event.zig

@@ -24,21 +24,20 @@ const parser = @import("../netsurf.zig");
 const generate = @import("../../runtime/generate.zig");
 
 const Page = @import("../page.zig").Page;
+const Node = @import("../dom/node.zig").Node;
 const DOMException = @import("../dom/exceptions.zig").DOMException;
 const EventTarget = @import("../dom/event_target.zig").EventTarget;
 const EventTargetUnion = @import("../dom/event_target.zig").Union;
+const AbortSignal = @import("../html/AbortController.zig").AbortSignal;
 
 const CustomEvent = @import("custom_event.zig").CustomEvent;
 const ProgressEvent = @import("../xhr/progress_event.zig").ProgressEvent;
 const MouseEvent = @import("mouse_event.zig").MouseEvent;
+const ErrorEvent = @import("../html/error_event.zig").ErrorEvent;
+const MessageEvent = @import("../dom/MessageChannel.zig").MessageEvent;
 
 // Event interfaces
-pub const Interfaces = .{
-    Event,
-    CustomEvent,
-    ProgressEvent,
-    MouseEvent,
-};
+pub const Interfaces = .{ Event, CustomEvent, ProgressEvent, MouseEvent, ErrorEvent, MessageEvent };
 
 pub const Union = generate.Union(Interfaces);
 
@@ -58,10 +57,12 @@ pub const Event = struct {
 
     pub fn toInterface(evt: *parser.Event) !Union {
         return switch (try parser.eventGetInternalType(evt)) {
-            .event => .{ .Event = evt },
+            .event, .abort_signal, .xhr_event => .{ .Event = evt },
             .custom_event => .{ .CustomEvent = @as(*CustomEvent, @ptrCast(evt)).* },
             .progress_event => .{ .ProgressEvent = @as(*ProgressEvent, @ptrCast(evt)).* },
             .mouse_event => .{ .MouseEvent = @as(*parser.MouseEvent, @ptrCast(evt)) },
+            .error_event => .{ .ErrorEvent = @as(*ErrorEvent, @ptrCast(evt)).* },
+            .message_event => .{ .MessageEvent = @as(*MessageEvent, @ptrCast(evt)).* },
         };
     }
 
@@ -109,8 +110,11 @@ pub const Event = struct {
         return try parser.eventIsTrusted(self);
     }
 
-    pub fn get_timestamp(self: *parser.Event) !u32 {
-        return try parser.eventTimestamp(self);
+    // Even though this is supposed to to provide microsecond resolution, browser
+    // return coarser values to protect against fingerprinting. libdom returns
+    // seconds, which is good enough.
+    pub fn get_timeStamp(self: *parser.Event) !u32 {
+        return parser.eventTimestamp(self);
     }
 
     // Methods
@@ -139,6 +143,64 @@ pub const Event = struct {
     pub fn _preventDefault(self: *parser.Event) !void {
         return try parser.eventPreventDefault(self);
     }
+
+    pub fn _composedPath(self: *parser.Event, page: *Page) ![]const EventTargetUnion {
+        const et_ = try parser.eventTarget(self);
+        const et = et_ orelse return &.{};
+
+        var node: ?*parser.Node = switch (try parser.eventTargetInternalType(et)) {
+            .libdom_node => @as(*parser.Node, @ptrCast(et)),
+            .plain => parser.eventTargetToNode(et),
+            else => {
+                // Window, XHR, MessagePort, etc...no path beyond the event itself
+                return &.{try EventTarget.toInterface(et, page)};
+            },
+        };
+
+        const arena = page.call_arena;
+        var path: std.ArrayListUnmanaged(EventTargetUnion) = .empty;
+        while (node) |n| {
+            try path.append(arena, .{
+                .node = try Node.toInterface(n),
+            });
+
+            node = try parser.nodeParentNode(n);
+            if (node == null and try parser.nodeType(n) == .document_fragment) {
+                // we have a non-continuous hook from a shadowroot to its host (
+                // it's parent element). libdom doesn't really support ShdowRoots
+                // and, for the most part, that works out well since it naturally
+                // provides isolation. But events don't follow the same
+                // shadowroot isolation as most other things, so, if this is
+                // a parent-less document fragment, we need to check if it has
+                // a host.
+                if (parser.documentFragmentGetHost(@ptrCast(n))) |host| {
+                    node = host;
+
+                    // If a document fragment has a host, then that host
+                    // _has_ to have a state and that state _has_ to have
+                    // a shadow_root field. All of this is set in Element._attachShadow
+                    if (page.getNodeState(host).?.shadow_root.?.mode == .closed) {
+                        // if the shadow root is closed, then the composedPath
+                        // starts at the host element.
+                        path.clearRetainingCapacity();
+                    }
+                } else {
+                    // Our document fragement has no parent and no host, we
+                    // can break out of the loop.
+                    break;
+                }
+            }
+        }
+
+        if (path.getLastOrNull()) |last| {
+            // the Window isn't part of the DOM hierarchy, but for events, it
+            // is, so we need to glue it on.
+            if (last.node == .HTMLDocument and last.node.HTMLDocument == page.window.document) {
+                try path.append(arena, .{ .node = .{ .Window = &page.window } });
+            }
+        }
+        return path.items;
+    }
 };
 
 pub const EventHandler = struct {
@@ -178,7 +240,7 @@ pub const EventHandler = struct {
             // that the listener won't call preventDefault() and thus can safely
             // run the default as needed).
             passive: ?bool,
-            signal: ?bool, // currently does nothing
+            signal: ?*AbortSignal, // currently does nothing
         };
     };
 
@@ -191,25 +253,42 @@ pub const EventHandler = struct {
     ) !?*EventHandler {
         var once = false;
         var capture = false;
+        var signal: ?*AbortSignal = null;
+
         if (opts_) |opts| {
             switch (opts) {
                 .capture => |c| capture = c,
                 .flags => |f| {
-                    // Done this way so that, for common cases that _only_ set
-                    // capture, i.e. {captrue: true}, it works.
-                    // But for any case that sets any of the other flags, we
-                    // error. If we don't error, this function call would succeed
-                    // but the behavior might be wrong. At this point, it's
-                    // better to be explicit and error.
-                    if (f.signal orelse false) return error.NotImplemented;
                     once = f.once orelse false;
+                    signal = f.signal orelse null;
                     capture = f.capture orelse false;
                 },
             }
         }
-
         const callback = (try listener.callback(target)) orelse return null;
 
+        if (signal) |s| {
+            const signal_target = parser.toEventTarget(AbortSignal, s);
+
+            const scb = try allocator.create(SignalCallback);
+            scb.* = .{
+                .target = target,
+                .capture = capture,
+                .callback_id = callback.id,
+                .typ = try allocator.dupe(u8, typ),
+                .signal_target = signal_target,
+                .signal_listener = undefined,
+                .node = .{ .func = SignalCallback.handle },
+            };
+
+            scb.signal_listener = try parser.eventTargetAddEventListener(
+                signal_target,
+                "abort",
+                &scb.node,
+                false,
+            );
+        }
+
         // check if event target has already this listener
         if (try parser.eventTargetHasListener(target, typ, capture, callback.id) != null) {
             return null;
@@ -265,110 +344,51 @@ pub const EventHandler = struct {
     }
 };
 
+const SignalCallback = struct {
+    typ: []const u8,
+    capture: bool,
+    callback_id: usize,
+    node: parser.EventNode,
+    target: *parser.EventTarget,
+    signal_target: *parser.EventTarget,
+    signal_listener: *parser.EventListener,
+
+    fn handle(node: *parser.EventNode, _: *parser.Event) void {
+        const self: *SignalCallback = @fieldParentPtr("node", node);
+        self._handle() catch |err| {
+            log.err(.app, "event signal handler", .{ .err = err });
+        };
+    }
+
+    fn _handle(self: *SignalCallback) !void {
+        const lst = try parser.eventTargetHasListener(
+            self.target,
+            self.typ,
+            self.capture,
+            self.callback_id,
+        );
+        if (lst == null) {
+            return;
+        }
+
+        try parser.eventTargetRemoveEventListener(
+            self.target,
+            self.typ,
+            lst.?,
+            self.capture,
+        );
+
+        // remove the abort signal listener itself
+        try parser.eventTargetRemoveEventListener(
+            self.signal_target,
+            "abort",
+            self.signal_listener,
+            false,
+        );
+    }
+};
+
 const testing = @import("../../testing.zig");
-test "Browser.Event" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let content = document.getElementById('content')", "undefined" },
-        .{ "let para = document.getElementById('para')", "undefined" },
-        .{ "var nb = 0; var evt", "undefined" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{
-            \\ content.addEventListener('target', function(e) {
-            \\  evt = e; nb = nb + 1;
-            \\  e.preventDefault();
-            \\ })
-            ,
-            "undefined",
-        },
-        .{ "content.dispatchEvent(new Event('target', {bubbles: true, cancelable: true}))", "false" },
-        .{ "nb", "1" },
-        .{ "evt.target === content", "true" },
-        .{ "evt.bubbles", "true" },
-        .{ "evt.cancelable", "true" },
-        .{ "evt.defaultPrevented", "true" },
-        .{ "evt.isTrusted", "true" },
-        .{ "evt.timestamp > 1704063600", "true" }, // 2024/01/01 00:00
-        // event.type, event.currentTarget, event.phase checked in EventTarget
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb = 0", "0" },
-        .{
-            \\ content.addEventListener('stop',function(e) {
-            \\    e.stopPropagation();
-            \\    nb = nb + 1;
-            \\  }, true)
-            ,
-            "undefined",
-        },
-        // the following event listener will not be invoked
-        .{
-            \\  para.addEventListener('stop',function(e) {
-            \\    nb = nb + 1;
-            \\  })
-            ,
-            "undefined",
-        },
-        .{ "para.dispatchEvent(new Event('stop'))", "true" },
-        .{ "nb", "1" }, // will be 2 if event was not stopped at content event listener
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb = 0", "0" },
-        .{
-            \\  content.addEventListener('immediate', function(e) {
-            \\    e.stopImmediatePropagation();
-            \\    nb = nb + 1;
-            \\  })
-            ,
-            "undefined",
-        },
-        // the following event listener will not be invoked
-        .{
-            \\  content.addEventListener('immediate', function(e) {
-            \\    nb = nb + 1;
-            \\  })
-            ,
-            "undefined",
-        },
-        .{ "content.dispatchEvent(new Event('immediate'))", "true" },
-        .{ "nb", "1" }, // will be 2 if event was not stopped at first content event listener
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb = 0", "0" },
-        .{
-            \\  content.addEventListener('legacy', function(e) {
-            \\     evt = e; nb = nb + 1;
-            \\  })
-            ,
-            "undefined",
-        },
-        .{ "let evtLegacy = document.createEvent('Event')", "undefined" },
-        .{ "evtLegacy.initEvent('legacy')", "undefined" },
-        .{ "content.dispatchEvent(evtLegacy)", "true" },
-        .{ "nb", "1" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "var nb = 0; var evt = null; function cbk(event) { nb ++; evt=event; }", "undefined" },
-        .{ "document.addEventListener('count', cbk)", "undefined" },
-        .{ "document.removeEventListener('count', cbk)", "undefined" },
-        .{ "document.dispatchEvent(new Event('count'))", "true" },
-        .{ "nb", "0" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "nb = 0; function cbk(event) { nb ++; }", null },
-        .{ "document.addEventListener('count', cbk, {once: true})", null },
-        .{ "document.dispatchEvent(new Event('count'))", "true" },
-        .{ "document.dispatchEvent(new Event('count'))", "true" },
-        .{ "document.dispatchEvent(new Event('count'))", "true" },
-        .{ "nb", "1" },
-    }, .{});
+test "Browser: Event" {
+    try testing.htmlRunner("events/event.html");
 }

src/browser/events/mouse_event.zig

@@ -17,7 +17,7 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const log = std.log.scoped(.mouse_event);
+const log = @import("../../log.zig");
 
 const parser = @import("../netsurf.zig");
 const Event = @import("event.zig").Event;
@@ -68,10 +68,6 @@ pub const MouseEvent = struct {
             .button = @intFromEnum(opts.button),
         });
 
-        if (!std.mem.eql(u8, event_type, "click")) {
-            log.warn("MouseEvent currently only supports listeners for 'click' events!", .{});
-        }
-
         return mouse_event;
     }
 
@@ -107,34 +103,6 @@ pub const MouseEvent = struct {
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.MouseEvent" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        // Default MouseEvent
-        .{ "let event = new MouseEvent('click')", "undefined" },
-        .{ "event.type", "click" },
-        .{ "event instanceof MouseEvent", "true" },
-        .{ "event instanceof Event", "true" },
-        .{ "event.clientX", "0" },
-        .{ "event.clientY", "0" },
-        .{ "event.screenX", "0" },
-        .{ "event.screenY", "0" },
-        // MouseEvent with parameters
-        .{ "let new_event = new MouseEvent('click', { 'button': 0, 'clientX': 10, 'clientY': 20 })", "undefined" },
-        .{ "new_event.button", "0" },
-        .{ "new_event.x", "10" },
-        .{ "new_event.y", "20" },
-        .{ "new_event.screenX", "10" },
-        .{ "new_event.screenY", "20" },
-        // MouseEvent Listener
-        .{ "let me = new MouseEvent('click')", "undefined" },
-        .{ "me instanceof Event", "true" },
-        .{ "var eevt = null; function ccbk(event) { eevt = event; }", "undefined" },
-        .{ "document.addEventListener('click', ccbk)", "undefined" },
-        .{ "document.dispatchEvent(me)", "true" },
-        .{ "eevt.type", "click" },
-        .{ "eevt instanceof MouseEvent", "true" },
-    }, .{});
+test "Browser: Events.Mouse" {
+    try testing.htmlRunner("events/mouse.html");
 }

src/browser/html/AbortController.zig

@@ -0,0 +1,181 @@
+// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+const log = @import("../../log.zig");
+const parser = @import("../netsurf.zig");
+const Env = @import("../env.zig").Env;
+const Page = @import("../page.zig").Page;
+const EventTarget = @import("../dom/event_target.zig").EventTarget;
+
+pub const Interfaces = .{
+    AbortController,
+    AbortSignal,
+};
+
+const AbortController = @This();
+
+signal: *AbortSignal,
+
+pub fn constructor(page: *Page) !AbortController {
+    // Why do we allocate this rather than storing directly in the struct?
+    // https://github.com/lightpanda-io/project/discussions/165
+    const signal = try page.arena.create(AbortSignal);
+    signal.* = .init;
+
+    return .{
+        .signal = signal,
+    };
+}
+
+pub fn get_signal(self: *AbortController) *AbortSignal {
+    return self.signal;
+}
+
+pub fn _abort(self: *AbortController, reason_: ?[]const u8) !void {
+    return self.signal.abort(reason_);
+}
+
+pub const AbortSignal = struct {
+    const DEFAULT_REASON = "AbortError";
+
+    pub const prototype = *EventTarget;
+    proto: parser.EventTargetTBase = .{ .internal_target_type = .abort_signal },
+
+    aborted: bool,
+    reason: ?[]const u8,
+
+    pub const init: AbortSignal = .{
+        .reason = null,
+        .aborted = false,
+    };
+
+    pub fn static_abort(reason_: ?[]const u8) AbortSignal {
+        return .{
+            .aborted = true,
+            .reason = reason_ orelse DEFAULT_REASON,
+        };
+    }
+
+    pub fn static_timeout(delay: u32, page: *Page) !*AbortSignal {
+        const callback = try page.arena.create(TimeoutCallback);
+        callback.* = .{
+            .signal = .init,
+        };
+
+        try page.scheduler.add(callback, TimeoutCallback.run, delay, .{ .name = "abort_signal" });
+        return &callback.signal;
+    }
+
+    pub fn get_aborted(self: *const AbortSignal) bool {
+        return self.aborted;
+    }
+
+    fn abort(self: *AbortSignal, reason_: ?[]const u8) !void {
+        self.aborted = true;
+        self.reason = reason_ orelse DEFAULT_REASON;
+
+        const abort_event = try parser.eventCreate();
+        try parser.eventSetInternalType(abort_event, .abort_signal);
+
+        defer parser.eventDestroy(abort_event);
+        try parser.eventInit(abort_event, "abort", .{});
+        _ = try parser.eventTargetDispatchEvent(
+            parser.toEventTarget(AbortSignal, self),
+            abort_event,
+        );
+    }
+
+    const Reason = union(enum) {
+        reason: []const u8,
+        undefined: void,
+    };
+    pub fn get_reason(self: *const AbortSignal) Reason {
+        if (self.reason) |r| {
+            return .{ .reason = r };
+        }
+        return .{ .undefined = {} };
+    }
+
+    const ThrowIfAborted = union(enum) {
+        exception: Env.Exception,
+        undefined: void,
+    };
+    pub fn _throwIfAborted(self: *const AbortSignal, page: *Page) ThrowIfAborted {
+        if (self.aborted) {
+            const ex = page.main_context.throw(self.reason orelse DEFAULT_REASON);
+            return .{ .exception = ex };
+        }
+        return .{ .undefined = {} };
+    }
+};
+
+const TimeoutCallback = struct {
+    signal: AbortSignal,
+
+    fn run(ctx: *anyopaque) ?u32 {
+        const self: *TimeoutCallback = @ptrCast(@alignCast(ctx));
+        self.signal.abort("TimeoutError") catch |err| {
+            log.warn(.app, "abort signal timeout", .{ .err = err });
+        };
+        return null;
+    }
+};
+
+const testing = @import("../../testing.zig");
+test "Browser.HTML.AbortController" {
+    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
+    defer runner.deinit();
+
+    try runner.testCases(&.{
+        .{ "var called = 0", null },
+        .{ "var a1 = new AbortController()", null },
+        .{ "var s1 = a1.signal", null },
+        .{ "s1.throwIfAborted()", "undefined" },
+        .{ "s1.reason", "undefined" },
+        .{ "var target;", null },
+        .{
+            \\ s1.addEventListener('abort', (e) => {
+            \\   called += 1;
+            \\   target = e.target;
+            \\
+            \\ });
+            ,
+            null,
+        },
+        .{ "a1.abort()", null },
+        .{ "s1.aborted", "true" },
+        .{ "target == s1", "true" },
+        .{ "s1.reason", "AbortError" },
+        .{ "called", "1" },
+    }, .{});
+
+    try runner.testCases(&.{
+        .{ "var s2 = AbortSignal.abort('over 9000')", null },
+        .{ "s2.aborted", "true" },
+        .{ "s2.reason", "over 9000" },
+        .{ "AbortSignal.abort().reason", "AbortError" },
+    }, .{});
+
+    try runner.testCases(&.{
+        .{ "var s3 = AbortSignal.timeout(10)", null },
+        .{ "s3.aborted", "true" },
+        .{ "s3.reason", "TimeoutError" },
+        .{ "try { s3.throwIfAborted() } catch (e) { e }", "Error: TimeoutError" },
+    }, .{});
+}

src/browser/html/DataSet.zig

@@ -0,0 +1,97 @@
+// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+const std = @import("std");
+const parser = @import("../netsurf.zig");
+const Env = @import("../env.zig").Env;
+const Page = @import("../page.zig").Page;
+
+const Allocator = std.mem.Allocator;
+
+const DataSet = @This();
+
+element: *parser.Element,
+
+pub fn named_get(self: *const DataSet, name: []const u8, _: *bool, page: *Page) !Env.UndefinedOr([]const u8) {
+    const normalized_name = try normalize(page.call_arena, name);
+    if (try parser.elementGetAttribute(self.element, normalized_name)) |value| {
+        return .{ .value = value };
+    }
+    return .undefined;
+}
+
+pub fn named_set(self: *DataSet, name: []const u8, value: []const u8, _: *bool, page: *Page) !void {
+    const normalized_name = try normalize(page.call_arena, name);
+    try parser.elementSetAttribute(self.element, normalized_name, value);
+}
+
+pub fn named_delete(self: *DataSet, name: []const u8, _: *bool, page: *Page) !void {
+    const normalized_name = try normalize(page.call_arena, name);
+    try parser.elementRemoveAttribute(self.element, normalized_name);
+}
+
+fn normalize(allocator: Allocator, name: []const u8) ![]const u8 {
+    var upper_count: usize = 0;
+    for (name) |c| {
+        if (std.ascii.isUpper(c)) {
+            upper_count += 1;
+        }
+    }
+    // for every upper-case letter, we'll probably need a dash before it
+    // and we need the 'data-' prefix
+    var normalized = try allocator.alloc(u8, name.len + upper_count + 5);
+
+    @memcpy(normalized[0..5], "data-");
+    if (upper_count == 0) {
+        @memcpy(normalized[5..], name);
+        return normalized;
+    }
+
+    var pos: usize = 5;
+    for (name) |c| {
+        if (std.ascii.isUpper(c)) {
+            normalized[pos] = '-';
+            pos += 1;
+            normalized[pos] = c + 32;
+        } else {
+            normalized[pos] = c;
+        }
+        pos += 1;
+    }
+    return normalized;
+}
+
+const testing = @import("../../testing.zig");
+test "Browser.HTML.DataSet" {
+    var runner = try testing.jsRunner(testing.tracking_allocator, .{ .html = "" });
+    defer runner.deinit();
+
+    try runner.testCases(&.{
+        .{ "let el1 = document.createElement('div')", null },
+        .{ "el1.dataset.x", "undefined" },
+        .{ "el1.dataset.x = '123'", "123" },
+        .{ "delete el1.dataset.x", "true" },
+        .{ "el1.dataset.x", "undefined" },
+        .{ "delete el1.dataset.other", "true" }, // yes, this is right
+
+        .{ "let ds1 = el1.dataset", null },
+        .{ "ds1.helloWorld = 'yes'", null },
+        .{ "el1.getAttribute('data-hello-world')", "yes" },
+        .{ "el1.setAttribute('data-this-will-work', 'positive')", null },
+        .{ "ds1.thisWillWork", "positive" },
+    }, .{});
+}

src/browser/html/document.zig

@@ -42,8 +42,12 @@ pub const HTMLDocument = struct {
     // JS funcs
     // --------
 
-    pub fn get_domain(self: *parser.DocumentHTML) ![]const u8 {
-        return try parser.documentHTMLGetDomain(self);
+    pub fn get_domain(self: *parser.DocumentHTML, page: *Page) ![]const u8 {
+        // libdom's document_html get_domain always returns null, this is
+        // the way MDN recommends getting the domain anyways, since document.domain
+        // is deprecated.
+        const location = try parser.documentHTMLGetLocation(Location, self) orelse return "";
+        return location.get_host(page);
     }
 
     pub fn set_domain(_: *parser.DocumentHTML, _: []const u8) ![]const u8 {
@@ -81,7 +85,10 @@ pub const HTMLDocument = struct {
 
     pub fn get_cookie(_: *parser.DocumentHTML, page: *Page) ![]const u8 {
         var buf: std.ArrayListUnmanaged(u8) = .{};
-        try page.cookie_jar.forRequest(&page.url.uri, buf.writer(page.arena), .{ .navigation = true, .is_http = false });
+        try page.cookie_jar.forRequest(&page.url.uri, buf.writer(page.arena), .{
+            .is_http = false,
+            .is_navigation = true,
+        });
         return buf.items;
     }
 
@@ -114,7 +121,9 @@ pub const HTMLDocument = struct {
         if (name.len == 0) return list;
 
         const root = parser.documentHTMLToNode(self);
-        var c = try collection.HTMLCollectionByName(arena, root, name, false);
+        var c = try collection.HTMLCollectionByName(arena, root, name, .{
+            .include_root = false,
+        });
 
         const ln = try c.get_length();
         var i: u32 = 0;
@@ -128,11 +137,15 @@ pub const HTMLDocument = struct {
     }
 
     pub fn get_images(self: *parser.DocumentHTML, page: *Page) !collection.HTMLCollection {
-        return try collection.HTMLCollectionByTagName(page.arena, parser.documentHTMLToNode(self), "img", false);
+        return try collection.HTMLCollectionByTagName(page.arena, parser.documentHTMLToNode(self), "img", .{
+            .include_root = false,
+        });
     }
 
     pub fn get_embeds(self: *parser.DocumentHTML, page: *Page) !collection.HTMLCollection {
-        return try collection.HTMLCollectionByTagName(page.arena, parser.documentHTMLToNode(self), "embed", false);
+        return try collection.HTMLCollectionByTagName(page.arena, parser.documentHTMLToNode(self), "embed", .{
+            .include_root = false,
+        });
     }
 
     pub fn get_plugins(self: *parser.DocumentHTML, page: *Page) !collection.HTMLCollection {
@@ -140,11 +153,15 @@ pub const HTMLDocument = struct {
     }
 
     pub fn get_forms(self: *parser.DocumentHTML, page: *Page) !collection.HTMLCollection {
-        return try collection.HTMLCollectionByTagName(page.arena, parser.documentHTMLToNode(self), "form", false);
+        return try collection.HTMLCollectionByTagName(page.arena, parser.documentHTMLToNode(self), "form", .{
+            .include_root = false,
+        });
     }
 
     pub fn get_scripts(self: *parser.DocumentHTML, page: *Page) !collection.HTMLCollection {
-        return try collection.HTMLCollectionByTagName(page.arena, parser.documentHTMLToNode(self), "script", false);
+        return try collection.HTMLCollectionByTagName(page.arena, parser.documentHTMLToNode(self), "script", .{
+            .include_root = false,
+        });
     }
 
     pub fn get_applets(_: *parser.DocumentHTML) !collection.HTMLCollection {
@@ -152,11 +169,15 @@ pub const HTMLDocument = struct {
     }
 
     pub fn get_links(self: *parser.DocumentHTML) !collection.HTMLCollection {
-        return try collection.HTMLCollectionByLinks(parser.documentHTMLToNode(self), false);
+        return try collection.HTMLCollectionByLinks(parser.documentHTMLToNode(self), .{
+            .include_root = false,
+        });
     }
 
     pub fn get_anchors(self: *parser.DocumentHTML) !collection.HTMLCollection {
-        return try collection.HTMLCollectionByAnchors(parser.documentHTMLToNode(self), false);
+        return try collection.HTMLCollectionByAnchors(parser.documentHTMLToNode(self), .{
+            .include_root = false,
+        });
     }
 
     pub fn get_all(self: *parser.DocumentHTML) collection.HTMLAllCollection {
@@ -188,7 +209,7 @@ pub const HTMLDocument = struct {
     }
 
     pub fn get_readyState(self: *parser.DocumentHTML, page: *Page) ![]const u8 {
-        const state = try page.getOrCreateNodeState(@alignCast(@ptrCast(self)));
+        const state = try page.getOrCreateNodeState(@ptrCast(@alignCast(self)));
         return @tagName(state.ready_state);
     }
 
@@ -233,19 +254,23 @@ pub const HTMLDocument = struct {
     // Since LightPanda requires the client to know what they are clicking on we do not return the underlying element at this moment
     // This can currenty only happen if the first pixel is clicked without having rendered any element. This will change when css properties are supported.
     // This returns an ElementUnion instead of a *Parser.Element in case the element somehow hasn't passed through the js runtime yet.
-    pub fn _elementFromPoint(_: *parser.DocumentHTML, x: f32, y: f32, page: *Page) !?ElementUnion {
-        const ix: i32 = @intFromFloat(@floor(x));
-        const iy: i32 = @intFromFloat(@floor(y));
-        const element = page.renderer.getElementAtPosition(ix, iy) orelse return null;
+    // While x and y should be f32, here we take i32 since that's what our
+    // "renderer" uses. By specifying i32 here, rather than f32 and doing the
+    // conversion ourself, we rely on v8's type conversion which is both more
+    // flexible (e.g. handles NaN) and will be more consistent with a browser.
+    pub fn _elementFromPoint(_: *parser.DocumentHTML, x: i32, y: i32, page: *Page) !?ElementUnion {
+        const element = page.renderer.getElementAtPosition(x, y) orelse return null;
         // TODO if pointer-events set to none the underlying element should be returned (parser.documentGetDocumentElement(self.document);?)
         return try Element.toInterface(element);
     }
 
     // Returns an array of all elements at the specified coordinates (relative to the viewport). The elements are ordered from the topmost to the bottommost box of the viewport.
-    pub fn _elementsFromPoint(_: *parser.DocumentHTML, x: f32, y: f32, page: *Page) ![]ElementUnion {
-        const ix: i32 = @intFromFloat(@floor(x));
-        const iy: i32 = @intFromFloat(@floor(y));
-        const element = page.renderer.getElementAtPosition(ix, iy) orelse return &.{};
+    // While x and y should be f32, here we take i32 since that's what our
+    // "renderer" uses. By specifying i32 here, rather than f32 and doing the
+    // conversion ourself, we rely on v8's type conversion which is both more
+    // flexible (e.g. handles NaN) and will be more consistent with a browser.
+    pub fn _elementsFromPoint(_: *parser.DocumentHTML, x: i32, y: i32, page: *Page) ![]ElementUnion {
+        const element = page.renderer.getElementAtPosition(x, y) orelse return &.{};
         // TODO if pointer-events set to none the underlying element should be returned (parser.documentGetDocumentElement(self.document);?)
 
         var list: std.ArrayListUnmanaged(ElementUnion) = .empty;
@@ -267,22 +292,24 @@ pub const HTMLDocument = struct {
     }
 
     pub fn documentIsLoaded(self: *parser.DocumentHTML, page: *Page) !void {
-        const state = try page.getOrCreateNodeState(@alignCast(@ptrCast(self)));
+        const state = try page.getOrCreateNodeState(@ptrCast(@alignCast(self)));
         state.ready_state = .interactive;
 
-        const evt = try parser.eventCreate();
-        defer parser.eventDestroy(evt);
-
         log.debug(.script_event, "dispatch event", .{
             .type = "DOMContentLoaded",
             .source = "document",
         });
+
+        const evt = try parser.eventCreate();
+        defer parser.eventDestroy(evt);
         try parser.eventInit(evt, "DOMContentLoaded", .{ .bubbles = true, .cancelable = true });
         _ = try parser.eventTargetDispatchEvent(parser.toEventTarget(parser.DocumentHTML, self), evt);
+
+        try page.window.dispatchForDocumentTarget(evt);
     }
 
     pub fn documentIsComplete(self: *parser.DocumentHTML, page: *Page) !void {
-        const state = try page.getOrCreateNodeState(@alignCast(@ptrCast(self)));
+        const state = try page.getOrCreateNodeState(@ptrCast(@alignCast(self)));
         state.ready_state = .complete;
     }
 };
@@ -303,7 +330,7 @@ test "Browser.HTML.Document" {
     }, .{});
 
     try runner.testCases(&.{
-        .{ "document.domain", "" },
+        .{ "document.domain", "lightpanda.io" },
         .{ "document.referrer", "" },
         .{ "document.title", "" },
         .{ "document.body.localName", "body" },

src/browser/html/error_event.zig

@@ -0,0 +1,86 @@
+// Copyright (C) 2023-2024  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+const Env = @import("../env.zig").Env;
+const parser = @import("../netsurf.zig");
+
+// https://developer.mozilla.org/en-US/docs/Web/API/ErrorEvent
+pub const ErrorEvent = struct {
+    pub const prototype = *parser.Event;
+    pub const union_make_copy = true;
+
+    proto: parser.Event,
+    message: []const u8,
+    filename: []const u8,
+    lineno: i32,
+    colno: i32,
+    @"error": ?Env.JsObject,
+
+    const ErrorEventInit = struct {
+        message: []const u8 = "",
+        filename: []const u8 = "",
+        lineno: i32 = 0,
+        colno: i32 = 0,
+        @"error": ?Env.JsObject = null,
+    };
+
+    pub fn constructor(event_type: []const u8, opts: ?ErrorEventInit) !ErrorEvent {
+        const event = try parser.eventCreate();
+        defer parser.eventDestroy(event);
+        try parser.eventInit(event, event_type, .{});
+        try parser.eventSetInternalType(event, .event);
+
+        const o = opts orelse ErrorEventInit{};
+
+        return .{
+            .proto = event.*,
+            .message = o.message,
+            .filename = o.filename,
+            .lineno = o.lineno,
+            .colno = o.colno,
+            .@"error" = if (o.@"error") |e| try e.persist() else null,
+        };
+    }
+
+    pub fn get_message(self: *const ErrorEvent) []const u8 {
+        return self.message;
+    }
+
+    pub fn get_filename(self: *const ErrorEvent) []const u8 {
+        return self.filename;
+    }
+
+    pub fn get_lineno(self: *const ErrorEvent) i32 {
+        return self.lineno;
+    }
+
+    pub fn get_colno(self: *const ErrorEvent) i32 {
+        return self.colno;
+    }
+
+    pub fn get_error(self: *const ErrorEvent) Env.UndefinedOr(Env.JsObject) {
+        if (self.@"error") |e| {
+            return .{ .value = e };
+        }
+        return .undefined;
+    }
+};
+
+const testing = @import("../../testing.zig");
+test "Browser: HTML.ErrorEvent" {
+    try testing.htmlRunner("html/error_event.html");
+}

src/browser/html/html.zig

@@ -36,5 +36,8 @@ pub const Interfaces = .{
     History,
     Location,
     MediaQueryList,
+    @import("DataSet.zig"),
     @import("screen.zig").Interfaces,
+    @import("error_event.zig").ErrorEvent,
+    @import("AbortController.zig").Interfaces,
 };

src/browser/html/iframe.zig

@@ -0,0 +1,30 @@
+// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+
+const parser = @import("../netsurf.zig");
+const Page = @import("../page.zig").Page;
+const HTMLElement = @import("elements.zig").HTMLElement;
+
+// https://html.spec.whatwg.org/multipage/iframe-embed-object.html#htmliframeelement
+pub const HTMLIFrameElement = struct {
+    pub const Self = parser.IFrame;
+    pub const prototype = *HTMLElement;
+    pub const subtype = .node;
+};

src/browser/html/media_query_list.zig

@@ -26,7 +26,7 @@ pub const MediaQueryList = struct {
 
     // Extend libdom event target for pure zig struct.
     // This is not safe as it relies on a structure layout that isn't guaranteed
-    base: parser.EventTargetTBase = parser.EventTargetTBase{},
+    base: parser.EventTargetTBase = parser.EventTargetTBase{ .internal_target_type = .media_query_list },
 
     matches: bool,
     media: []const u8,

src/browser/html/screen.zig

@@ -18,6 +18,7 @@
 
 const std = @import("std");
 
+const parser = @import("../netsurf.zig");
 const EventTarget = @import("../dom/event_target.zig").EventTarget;
 
 pub const Interfaces = .{
@@ -29,6 +30,8 @@ pub const Interfaces = .{
 pub const Screen = struct {
     pub const prototype = *EventTarget;
 
+    proto: parser.EventTargetTBase = .{ .internal_target_type = .screen },
+
     height: u32 = 1080,
     width: u32 = 1920,
     // https://developer.mozilla.org/en-US/docs/Web/API/Screen/colorDepth
@@ -83,6 +86,7 @@ pub const ScreenOrientation = struct {
 
     angle: u32 = 0,
     type: ScreenOrientationType,
+    proto: parser.EventTargetTBase = .{ .internal_target_type = .screen_orientation },
 
     pub fn get_angle(self: *const ScreenOrientation) u32 {
         return self.angle;
@@ -94,16 +98,6 @@ pub const ScreenOrientation = struct {
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.HTML.Screen" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "let screen = window.screen", "undefined" },
-        .{ "screen.width === 1920", "true" },
-        .{ "screen.height === 1080", "true" },
-        .{ "let orientation = screen.orientation", "undefined" },
-        .{ "orientation.angle === 0", "true" },
-        .{ "orientation.type === \"landscape-primary\"", "true" },
-    }, .{});
+test "Browser: HTML.Screen" {
+    try testing.htmlRunner("html/screen.html");
 }

src/browser/html/select.zig

@@ -18,8 +18,16 @@
 const std = @import("std");
 
 const parser = @import("../netsurf.zig");
-const HTMLElement = @import("elements.zig").HTMLElement;
+const collection = @import("../dom/html_collection.zig");
+
 const Page = @import("../page.zig").Page;
+const HTMLElement = @import("elements.zig").HTMLElement;
+
+pub const Interfaces = .{
+    HTMLSelectElement,
+    HTMLOptionElement,
+    HTMLOptionsCollection,
+};
 
 pub const HTMLSelectElement = struct {
     pub const Self = parser.Select;
@@ -56,7 +64,7 @@ pub const HTMLSelectElement = struct {
     }
 
     pub fn get_selectedIndex(select: *parser.Select, page: *Page) !i32 {
-        const state = try page.getOrCreateNodeState(@alignCast(@ptrCast(select)));
+        const state = try page.getOrCreateNodeState(@ptrCast(@alignCast(select)));
         const selected_index = try parser.selectGetSelectedIndex(select);
 
         // See the explicit_index_set field documentation
@@ -75,7 +83,7 @@ pub const HTMLSelectElement = struct {
     // Libdom's dom_html_select_select_set_selected_index will crash if index
     // is out of range, and it doesn't properly unset options
     pub fn set_selectedIndex(select: *parser.Select, index: i32, page: *Page) !void {
-        var state = try page.getOrCreateNodeState(@alignCast(@ptrCast(select)));
+        var state = try page.getOrCreateNodeState(@ptrCast(@alignCast(select)));
         state.explicit_index_set = true;
 
         const options = try parser.selectGetOptions(select);
@@ -89,6 +97,105 @@ pub const HTMLSelectElement = struct {
             try parser.optionSetSelected(option, true);
         }
     }
+
+    pub fn get_options(select: *parser.Select) HTMLOptionsCollection {
+        return .{
+            .select = select,
+            .proto = collection.HTMLCollectionChildren(@ptrCast(@alignCast(select)), .{
+                .mutable = true,
+                .include_root = false,
+            }),
+        };
+    }
+};
+
+pub const HTMLOptionElement = struct {
+    pub const Self = parser.Option;
+    pub const prototype = *HTMLElement;
+    pub const subtype = .node;
+
+    pub fn get_value(self: *parser.Option) ![]const u8 {
+        return parser.optionGetValue(self);
+    }
+    pub fn set_value(self: *parser.Option, value: []const u8) !void {
+        return parser.optionSetValue(self, value);
+    }
+
+    pub fn get_label(self: *parser.Option) ![]const u8 {
+        return parser.optionGetLabel(self);
+    }
+    pub fn set_label(self: *parser.Option, label: []const u8) !void {
+        return parser.optionSetLabel(self, label);
+    }
+
+    pub fn get_selected(self: *parser.Option) !bool {
+        return parser.optionGetSelected(self);
+    }
+    pub fn set_selected(self: *parser.Option, value: bool) !void {
+        return parser.optionSetSelected(self, value);
+    }
+
+    pub fn get_disabled(self: *parser.Option) !bool {
+        return parser.optionGetDisabled(self);
+    }
+    pub fn set_disabled(self: *parser.Option, value: bool) !void {
+        return parser.optionSetDisabled(self, value);
+    }
+
+    pub fn get_text(self: *parser.Option) ![]const u8 {
+        return parser.optionGetText(self);
+    }
+
+    pub fn get_form(self: *parser.Option) !?*parser.Form {
+        return parser.optionGetForm(self);
+    }
+};
+
+pub const HTMLOptionsCollection = struct {
+    pub const prototype = *collection.HTMLCollection;
+
+    proto: collection.HTMLCollection,
+    select: *parser.Select,
+
+    pub fn get_selectedIndex(self: *HTMLOptionsCollection, page: *Page) !i32 {
+        return HTMLSelectElement.get_selectedIndex(self.select, page);
+    }
+
+    pub fn set_selectedIndex(self: *HTMLOptionsCollection, index: i32, page: *Page) !void {
+        return HTMLSelectElement.set_selectedIndex(self.select, index, page);
+    }
+
+    const BeforeOpts = union(enum) {
+        index: u32,
+        option: *parser.Option,
+    };
+    pub fn _add(self: *HTMLOptionsCollection, option: *parser.Option, before_: ?BeforeOpts) !void {
+        const Node = @import("../dom/node.zig").Node;
+        const before = before_ orelse {
+            return self.appendOption(option);
+        };
+
+        const insert_before: *parser.Node = switch (before) {
+            .option => |o| @ptrCast(@alignCast(o)),
+            .index => |i| (try self.proto.item(i)) orelse return self.appendOption(option),
+        };
+        return Node.before(insert_before, &.{
+            .{ .node = @ptrCast(@alignCast(option)) },
+        });
+    }
+
+    pub fn _remove(self: *HTMLOptionsCollection, index: u32) !void {
+        const Node = @import("../dom/node.zig").Node;
+        const option = (try self.proto.item(index)) orelse return;
+        _ = try Node._removeChild(@ptrCast(@alignCast(self.select)), option);
+    }
+
+    fn appendOption(self: *HTMLOptionsCollection, option: *parser.Option) !void {
+        const Node = @import("../dom/node.zig").Node;
+        return Node.append(@ptrCast(@alignCast(self.select)), &.{
+            .{ .node = @ptrCast(@alignCast(option)) },
+        });
+    }
 };
 
 const testing = @import("../../testing.zig");
@@ -140,5 +247,32 @@ test "Browser.HTML.Select" {
 
         .{ "s.selectedIndex = -323", null },
         .{ "s.selectedIndex", "-1" },
+
+        .{ "let options = s.options", null },
+        .{ "options.length", "2" },
+        .{ "options.item(1).value", "o2" },
+        .{ "options.selectedIndex", "-1" },
+
+        .{ "let o3 = document.createElement('option');", null },
+        .{ "o3.value = 'o3';", null },
+        .{ "options.add(o3)", null },
+        .{ "options.length", "3" },
+        .{ "options.item(2).value", "o3" },
+
+        .{ "let o4 = document.createElement('option');", null },
+        .{ "o4.value = 'o4';", null },
+        .{ "options.add(o4, 1)", null },
+        .{ "options.length", "4" },
+        .{ "options.item(1).value", "o4" },
+
+        .{ "let o5 = document.createElement('option');", null },
+        .{ "o5.value = 'o5';", null },
+        .{ "options.add(o5, o3)", null },
+        .{ "options.length", "5" },
+        .{ "options.item(3).value", "o5" },
+
+        .{ "options.remove(3)", null },
+        .{ "options.length", "4" },
+        .{ "options.item(3).value", "o3" },
     }, .{});
 }

src/browser/html/window.zig

@@ -20,9 +20,8 @@ const std = @import("std");
 
 const log = @import("../../log.zig");
 const parser = @import("../netsurf.zig");
-const Function = @import("../env.zig").Function;
+const Env = @import("../env.zig").Env;
 const Page = @import("../page.zig").Page;
-const Loop = @import("../../runtime/loop.zig").Loop;
 
 const Navigator = @import("navigator.zig").Navigator;
 const History = @import("history.zig").History;
@@ -32,9 +31,13 @@ const Console = @import("../console/console.zig").Console;
 const EventTarget = @import("../dom/event_target.zig").EventTarget;
 const MediaQueryList = @import("media_query_list.zig").MediaQueryList;
 const Performance = @import("../dom/performance.zig").Performance;
-const CSSStyleDeclaration = @import("../cssom/css_style_declaration.zig").CSSStyleDeclaration;
-const CustomElementRegistry = @import("../webcomponents/custom_element_registry.zig").CustomElementRegistry;
+const CSSStyleDeclaration = @import("../cssom/CSSStyleDeclaration.zig");
 const Screen = @import("screen.zig").Screen;
+const domcss = @import("../dom/css.zig");
+const Css = @import("../css/css.zig").Css;
+
+const Function = Env.Function;
+const JsObject = Env.JsObject;
 
 const storage = @import("../storage/storage.zig");
 
@@ -44,7 +47,7 @@ pub const Window = struct {
     pub const prototype = *EventTarget;
 
     // Extend libdom event target for pure zig struct.
-    base: parser.EventTargetTBase = parser.EventTargetTBase{},
+    base: parser.EventTargetTBase = parser.EventTargetTBase{ .internal_target_type = .window },
 
     document: *parser.DocumentHTML,
     target: []const u8 = "",
@@ -54,14 +57,14 @@ pub const Window = struct {
 
     // counter for having unique timer ids
     timer_id: u30 = 0,
-    timers: std.AutoHashMapUnmanaged(u32, *TimerCallback) = .{},
+    timers: std.AutoHashMapUnmanaged(u32, void) = .{},
 
     crypto: Crypto = .{},
     console: Console = .{},
     navigator: Navigator = .{},
     performance: Performance,
-    custom_elements: CustomElementRegistry = .{},
     screen: Screen = .{},
+    css: Css = .{},
 
     pub fn create(target: ?[]const u8, navigator: ?Navigator) !Window {
         var fbs = std.io.fixedBufferStream("");
@@ -73,7 +76,7 @@ pub const Window = struct {
             .document = html_doc,
             .target = target orelse "",
             .navigator = navigator orelse .{},
-            .performance = .{ .time_origin = try std.time.Timer.start() },
+            .performance = Performance.init(),
         };
     }
 
@@ -83,7 +86,7 @@ pub const Window = struct {
     }
 
     pub fn replaceDocument(self: *Window, doc: *parser.DocumentHTML) !void {
-        self.performance.time_origin.reset(); // When to reset see: https://developer.mozilla.org/en-US/docs/Web/API/Performance/timeOrigin
+        self.performance.reset(); // When to reset see: https://developer.mozilla.org/en-US/docs/Web/API/Performance/timeOrigin
         self.document = doc;
         try parser.documentHTMLSetLocation(Location, doc, &self.location);
     }
@@ -124,7 +127,43 @@ pub const Window = struct {
         return self;
     }
 
-    // TODO: frames
+    // frames return the window itself, but accessing it via a pseudo
+    // array returns the Window object corresponding to the given frame or
+    // iframe.
+    // https://developer.mozilla.org/en-US/docs/Web/API/Window/frames
+    pub fn get_frames(self: *Window) *Window {
+        return self;
+    }
+
+    pub fn indexed_get(self: *Window, index: u32, has_value: *bool, page: *Page) !*Window {
+        const frames = try domcss.querySelectorAll(
+            page.call_arena,
+            parser.documentHTMLToNode(self.document),
+            "iframe",
+        );
+
+        if (index >= frames.nodes.items.len) {
+            has_value.* = false;
+            return undefined;
+        }
+
+        has_value.* = true;
+        // TODO return the correct frame's window
+        // frames.nodes.items[indexed]
+        return error.TODO;
+    }
+
+    // Retrieve the numbre of frames/iframes from the DOM dynamically.
+    pub fn get_length(self: *const Window, page: *Page) !u32 {
+        const frames = try domcss.querySelectorAll(
+            page.call_arena,
+            parser.documentHTMLToNode(self.document),
+            "iframe",
+        );
+
+        return frames.get_length();
+    }
+
     pub fn get_top(self: *Window) *Window {
         return self;
     }
@@ -167,41 +206,44 @@ pub const Window = struct {
         return &self.performance;
     }
 
-    pub fn get_customElements(self: *Window) *CustomElementRegistry {
-        return &self.custom_elements;
-    }
-
     pub fn get_screen(self: *Window) *Screen {
         return &self.screen;
     }
 
+    pub fn get_CSS(self: *Window) *Css {
+        return &self.css;
+    }
+
     pub fn _requestAnimationFrame(self: *Window, cbk: Function, page: *Page) !u32 {
-        return self.createTimeout(cbk, 5, page, .{ .animation_frame = true });
+        return self.createTimeout(cbk, 5, page, .{
+            .animation_frame = true,
+            .name = "animationFrame",
+            .low_priority = true,
+        });
     }
 
-    pub fn _cancelAnimationFrame(self: *Window, id: u32, page: *Page) !void {
-        const kv = self.timers.fetchRemove(id) orelse return;
-        return page.loop.cancel(kv.value.loop_id);
+    pub fn _cancelAnimationFrame(self: *Window, id: u32) !void {
+        _ = self.timers.remove(id);
     }
 
-    // TODO handle callback arguments.
-    pub fn _setTimeout(self: *Window, cbk: Function, delay: ?u32, page: *Page) !u32 {
-        return self.createTimeout(cbk, delay, page, .{});
+    pub fn _setTimeout(self: *Window, cbk: Function, delay: ?u32, params: []Env.JsObject, page: *Page) !u32 {
+        return self.createTimeout(cbk, delay, page, .{ .args = params, .name = "setTimeout" });
     }
 
-    // TODO handle callback arguments.
-    pub fn _setInterval(self: *Window, cbk: Function, delay: ?u32, page: *Page) !u32 {
-        return self.createTimeout(cbk, delay, page, .{ .repeat = true });
+    pub fn _setInterval(self: *Window, cbk: Function, delay: ?u32, params: []Env.JsObject, page: *Page) !u32 {
+        return self.createTimeout(cbk, delay, page, .{ .repeat = true, .args = params, .name = "setInterval" });
     }
 
-    pub fn _clearTimeout(self: *Window, id: u32, page: *Page) !void {
-        const kv = self.timers.fetchRemove(id) orelse return;
-        return page.loop.cancel(kv.value.loop_id);
+    pub fn _clearTimeout(self: *Window, id: u32) !void {
+        _ = self.timers.remove(id);
     }
 
-    pub fn _clearInterval(self: *Window, id: u32, page: *Page) !void {
-        const kv = self.timers.fetchRemove(id) orelse return;
-        return page.loop.cancel(kv.value.loop_id);
+    pub fn _clearInterval(self: *Window, id: u32) !void {
+        _ = self.timers.remove(id);
+    }
+
+    pub fn _queueMicrotask(self: *Window, cbk: Function, page: *Page) !u32 {
+        return self.createTimeout(cbk, 0, page, .{ .name = "queueMicrotask" });
     }
 
     pub fn _matchMedia(_: *const Window, media: []const u8, page: *Page) !MediaQueryList {
@@ -211,20 +253,30 @@ pub const Window = struct {
         };
     }
 
+    pub fn _btoa(_: *const Window, value: []const u8, page: *Page) ![]const u8 {
+        const Encoder = std.base64.standard.Encoder;
+        const out = try page.call_arena.alloc(u8, Encoder.calcSize(value.len));
+        return Encoder.encode(out, value);
+    }
+
+    pub fn _atob(_: *const Window, value: []const u8, page: *Page) ![]const u8 {
+        const Decoder = std.base64.standard.Decoder;
+        const size = Decoder.calcSizeForSlice(value) catch return error.InvalidCharacterError;
+
+        const out = try page.call_arena.alloc(u8, size);
+        Decoder.decode(out, value) catch return error.InvalidCharacterError;
+        return out;
+    }
+
     const CreateTimeoutOpts = struct {
+        name: []const u8,
+        args: []Env.JsObject = &.{},
         repeat: bool = false,
         animation_frame: bool = false,
+        low_priority: bool = false,
     };
-    fn createTimeout(self: *Window, cbk: Function, delay_: ?u32, page: *Page, comptime opts: CreateTimeoutOpts) !u32 {
+    fn createTimeout(self: *Window, cbk: Function, delay_: ?u32, page: *Page, opts: CreateTimeoutOpts) !u32 {
         const delay = delay_ orelse 0;
-        if (delay > 5000) {
-            log.warn(.user_script, "long timeout ignored", .{ .delay = delay, .interval = opts.repeat });
-            // self.timer_id is u30, so the largest value we can generate is
-            // 1_073_741_824. Returning 2_000_000_000 makes sure that clients
-            // can call cancelTimer/cancelInterval without breaking anything.
-            return 2_000_000_000;
-        }
-
         if (self.timers.count() > 512) {
             return error.TooManyTimeout;
         }
@@ -237,24 +289,36 @@ pub const Window = struct {
         if (gop.found_existing) {
             // this can only happen if we've created 2^31 timeouts.
             return error.TooManyTimeout;
+        } else {
+            gop.value_ptr.* = {};
         }
         errdefer _ = self.timers.remove(timer_id);
 
-        const delay_ms: u63 = @as(u63, delay) * std.time.ns_per_ms;
-        const callback = try arena.create(TimerCallback);
+        const args = opts.args;
+        var persisted_args: []Env.JsObject = &.{};
+        if (args.len > 0) {
+            persisted_args = try page.arena.alloc(Env.JsObject, args.len);
+            for (args, persisted_args) |a, *ca| {
+                ca.* = try a.persist();
+            }
+        }
 
+        const callback = try arena.create(TimerCallback);
         callback.* = .{
             .cbk = cbk,
-            .loop_id = 0, // we're going to set this to a real value shortly
             .window = self,
             .timer_id = timer_id,
-            .node = .{ .func = TimerCallback.run },
-            .repeat = if (opts.repeat) delay_ms else null,
+            .args = persisted_args,
             .animation_frame = opts.animation_frame,
+            // setting a repeat time of 0 is illegal, doing + 1 is a simple way to avoid that
+            .repeat = if (opts.repeat) delay + 1 else null,
         };
-        callback.loop_id = try page.loop.timeout(delay_ms, &callback.node);
 
-        gop.value_ptr.* = callback;
+        try page.scheduler.add(callback, TimerCallback.run, delay, .{
+            .name = opts.name,
+            .low_priority = opts.low_priority,
+        });
+
         return timer_id;
     }
 
@@ -277,35 +341,78 @@ pub const Window = struct {
             behavior: []const u8,
         };
     };
-    pub fn _scrollTo(_: *const Window, opts: ScrollToOpts, y: ?u32) void {
+    pub fn _scrollTo(self: *Window, opts: ScrollToOpts, y: ?u32) !void {
         _ = opts;
         _ = y;
+
+        {
+            const scroll_event = try parser.eventCreate();
+            defer parser.eventDestroy(scroll_event);
+
+            try parser.eventInit(scroll_event, "scroll", .{});
+            _ = try parser.eventTargetDispatchEvent(
+                parser.toEventTarget(Window, self),
+                scroll_event,
+            );
+        }
+
+        {
+            const scroll_end = try parser.eventCreate();
+            defer parser.eventDestroy(scroll_end);
+
+            try parser.eventInit(scroll_end, "scrollend", .{});
+            _ = try parser.eventTargetDispatchEvent(
+                parser.toEventTarget(parser.DocumentHTML, self.document),
+                scroll_end,
+            );
+        }
+    }
+
+    // libdom's document doesn't have a parent, which is correct, but
+    // breaks the event bubbling that happens for many events from
+    // document -> window.
+    // We need to force dispatch this event on the window, with the
+    // document target.
+    // In theory, we should do this for a lot of events and might need
+    // to come up with a good way to solve this more generically. But
+    // this specific event, and maybe a few others in the near future,
+    // are blockers.
+    // Worth noting that NetSurf itself appears to do something similar:
+    // https://github.com/netsurf-browser/netsurf/blob/a32e1a03e1c91ee9f0aa211937dbae7a96831149/content/handlers/html/html.c#L380
+    pub fn dispatchForDocumentTarget(self: *Window, evt: *parser.Event) !void {
+        // we assume that this evt has already been dispatched on the document
+        // and thus the target has already been set to the document.
+        return self.base.redispatchEvent(evt);
     }
 };
 
 const TimerCallback = struct {
-    // the internal loop id, need it when cancelling
-    loop_id: usize,
-
     // the id of our timer (windows.timers key)
     timer_id: u31,
 
+    // if false, we'll remove the timer_id from the window.timers lookup on run
+    repeat: ?u32,
+
     // The JavaScript callback to execute
     cbk: Function,
 
-    // This is the internal data that the event loop tracks. We'll get this
-    // back in run and, from it, can get our TimerCallback instance
-    node: Loop.CallbackNode = undefined,
-
-    // if the event should be repeated
-    repeat: ?u63 = null,
-
     animation_frame: bool = false,
 
     window: *Window,
 
-    fn run(node: *Loop.CallbackNode, repeat_delay: *?u63) void {
-        const self: *TimerCallback = @fieldParentPtr("node", node);
+    args: []Env.JsObject = &.{},
+
+    fn run(ctx: *anyopaque) ?u32 {
+        const self: *TimerCallback = @ptrCast(@alignCast(ctx));
+        if (self.repeat != null) {
+            if (self.window.timers.contains(self.timer_id) == false) {
+                // it was called
+                return null;
+            }
+        } else if (self.window.timers.remove(self.timer_id) == false) {
+            // it was cancelled
+            return null;
+        }
 
         var result: Function.Result = undefined;
 
@@ -313,99 +420,23 @@ const TimerCallback = struct {
         if (self.animation_frame) {
             call = self.cbk.tryCall(void, .{self.window.performance._now()}, &result);
         } else {
-            call = self.cbk.tryCall(void, .{}, &result);
+            call = self.cbk.tryCall(void, self.args, &result);
         }
 
         call catch {
-            log.debug(.user_script, "callback error", .{
+            log.warn(.user_script, "callback error", .{
                 .err = result.exception,
                 .stack = result.stack,
                 .source = "window timeout",
             });
         };
 
-        if (self.repeat) |r| {
-            // setInterval
-            repeat_delay.* = r;
-            return;
-        }
-
-        // setTimeout
-        _ = self.window.timers.remove(self.timer_id);
+        return self.repeat;
     }
 };
 
 const testing = @import("../../testing.zig");
-test "Browser.HTML.Window" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "window.parent === window", "true" },
-        .{ "window.top === window", "true" },
-    }, .{});
-
-    // requestAnimationFrame should be able to wait by recursively calling itself
-    // Note however that we in this test do not wait as the request is just send to the browser
-    try runner.testCases(&.{
-        .{
-            \\ let start = 0;
-            \\ function step(timestamp) {
-            \\    start = timestamp;
-            \\ }
-            ,
-            null,
-        },
-        .{ "requestAnimationFrame(step);", null }, // returned id is checked in the next test
-        .{ " start > 0", "true" },
-    }, .{});
-
-    // cancelAnimationFrame should be able to cancel a request with the given id
-    try runner.testCases(&.{
-        .{ "let request_id = requestAnimationFrame(timestamp => {});", null },
-        .{ "cancelAnimationFrame(request_id);", "undefined" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "innerHeight", "1" },
-        .{ "innerWidth", "1" }, // Width is 1 even if there are no elements
-        .{
-            \\ let div1 = document.createElement('div');
-            \\ document.body.appendChild(div1);
-            \\ div1.getClientRects();
-            ,
-            null,
-        },
-        .{
-            \\ let div2 = document.createElement('div');
-            \\ document.body.appendChild(div2);
-            \\ div2.getClientRects();
-            ,
-            null,
-        },
-        .{ "innerHeight", "1" },
-        .{ "innerWidth", "2" },
-    }, .{});
-
-    // cancelAnimationFrame should be able to cancel a request with the given id
-    try runner.testCases(&.{
-        .{ "let longCall = false;", null },
-        .{ "window.setTimeout(() => {longCall = true}, 5001);", null },
-        .{ "longCall;", "false" },
-    }, .{});
-
-    // window event target
-    try runner.testCases(&.{
-        .{
-            \\ let called = false;
-            \\ window.addEventListener("ready", (e) => {
-            \\   called = (e.currentTarget == window);
-            \\ }, {capture: false, once: false});
-            \\ const evt = new Event("ready", { bubbles: true, cancelable: false });
-            \\ window.dispatchEvent(evt);
-            \\ called;
-            ,
-            "true",
-        },
-    }, .{});
+test "Browser: Window" {
+    try testing.htmlRunner("window/window.html");
+    try testing.htmlRunner("window/frames.html");
 }

src/browser/markdown.zig

@@ -1,337 +0,0 @@
-// Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
-//
-// Francis Bouvier <francis@lightpanda.io>
-// Pierre Tachoire <pierre@lightpanda.io>
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Affero General Public License as
-// published by the Free Software Foundation, either version 3 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Affero General Public License for more details.
-//
-// You should have received a copy of the GNU Affero General Public License
-// along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-const std = @import("std");
-
-const parser = @import("netsurf.zig");
-const Walker = @import("dom/walker.zig").WalkerChildren;
-
-const URL = @import("../url.zig").URL;
-
-const NP = "\n\n";
-
-const Elem = struct {
-    inlin: bool = false,
-    list_order: ?u8 = null,
-    parent: ?*Elem = null,
-};
-
-const State = struct {
-    block: bool,
-    last_char: u8,
-    elem: ?*Elem = null,
-
-    fn is_inline(state: *State) bool {
-        if (state.elem == null) return false;
-        return state.elem.?.inlin;
-    }
-
-    fn last_char_space(state: *State) bool {
-        if (state.last_char == ' ' or state.last_char == '\n') return true;
-        return false;
-    }
-};
-
-// writer must be a std.io.Writer
-pub fn writeMarkdown(url: URL, doc: *parser.Document, writer: anytype) !void {
-    var state = State{ .block = true, .last_char = '\n' };
-    _ = try writeChildren(url, parser.documentToNode(doc), &state, writer);
-    try writer.writeAll("\n");
-}
-
-fn writeChildren(url: URL, root: *parser.Node, state: *State, writer: anytype) !void {
-    const walker = Walker{};
-    var next: ?*parser.Node = null;
-    while (true) {
-        next = try walker.get_next(root, next) orelse break;
-        try writeNode(url, next.?, state, writer);
-    }
-}
-
-fn ensureBlock(state: *State, writer: anytype) !void {
-    if (state.is_inline()) return;
-    if (!state.block) {
-        try writer.writeAll(NP);
-        state.last_char = '\n';
-        state.block = true;
-    }
-}
-
-fn writeInline(state: *State, text: []const u8, writer: anytype) !void {
-    try writer.writeAll(text);
-    state.last_char = text[text.len - 1];
-    if (state.block) state.block = false;
-}
-
-const order = [_][]const u8{
-    "1",  "2",  "3",  "4",  "5",  "6",  "7",  "8",  "9",  "10",
-    "11", "12", "13", "14", "15", "16", "17", "18", "19", "20",
-    "21", "22", "23", "24", "25", "26", "27", "28", "29", "30",
-    "31", "32", "33", "34", "35", "36", "37", "38", "39", "40",
-    "41", "42", "43", "44", "45", "46", "47", "48", "49", "50",
-};
-
-fn writeNode(url: URL, node: *parser.Node, state: *State, writer: anytype) anyerror!void {
-    switch (try parser.nodeType(node)) {
-        .element => {
-            const html_element: *parser.ElementHTML = @ptrCast(node);
-            const tag = try parser.elementHTMLGetTagType(html_element);
-
-            // debug
-            // try writer.writeAll("\nstart - ");
-            // try writer.writeAll(@tagName(tag));
-            // try writer.writeAll("\n");
-
-            switch (tag) {
-
-                // skip element, go to children
-                .html, .head, .meta, .link, .body, .span => {
-                    try writeChildren(url, node, state, writer);
-                },
-
-                // skip element and children
-                .title, .i, .script, .noscript, .undef, .style => {},
-
-                // generic elements
-                .h1, .h2, .h3, .h4, .h5, .h6 => {
-                    try ensureBlock(state, writer);
-                    if (!state.is_inline()) {
-                        switch (tag) {
-                            .h1 => try writeInline(state, "# ", writer),
-                            .h2 => try writeInline(state, "## ", writer),
-                            .h3 => try writeInline(state, "### ", writer),
-                            .h4 => try writeInline(state, "#### ", writer),
-                            .h5 => try writeInline(state, "##### ", writer),
-                            .h6 => try writeInline(state, "###### ", writer),
-                            else => @panic("only headers tags are supported here"),
-                        }
-                    }
-                    try writeChildren(url, node, state, writer);
-                    try ensureBlock(state, writer);
-                },
-
-                // containers and dividers
-                .header, .footer, .nav, .section, .div, .article, .p, .button, .form => {
-                    try ensureBlock(state, writer);
-                    try writeChildren(url, node, state, writer);
-                    try ensureBlock(state, writer);
-                },
-                .br => {
-                    try ensureBlock(state, writer);
-                    try writeChildren(url, node, state, writer);
-                },
-                .hr => {
-                    try ensureBlock(state, writer);
-                    try writeInline(state, "---", writer);
-                    try ensureBlock(state, writer);
-                },
-
-                // styling
-                .b => {
-                    var elem = Elem{ .parent = state.elem, .inlin = true };
-                    state.elem = &elem;
-                    defer state.elem = elem.parent;
-                    try writeInline(state, "**", writer);
-                    try writeChildren(url, node, state, writer);
-                    try writeInline(state, "**", writer);
-                },
-
-                // specific elements
-                .a => {
-                    if (!state.last_char_space()) try writeInline(state, " ", writer);
-                    var elem = Elem{ .parent = state.elem, .inlin = true };
-                    state.elem = &elem;
-                    defer state.elem = elem.parent;
-                    const element = parser.nodeToElement(node);
-                    if (try getAttributeValue(element, "href")) |href| {
-                        try writeInline(state, "[", writer);
-                        try writeChildren(url, node, state, writer);
-                        try writeInline(state, "](", writer);
-                        // handle relative path
-                        if (href[0] == '/') {
-                            try writeInline(state, url.scheme(), writer);
-                            try writeInline(state, "://", writer);
-                            try writeInline(state, url.host(), writer);
-                        }
-                        try writeInline(state, href, writer);
-                        try writeInline(state, ")", writer);
-                    } else {
-                        try writeChildren(url, node, state, writer);
-                    }
-                },
-                .img => {
-                    var elem = Elem{ .parent = state.elem, .inlin = true };
-                    state.elem = &elem;
-                    defer state.elem = elem.parent;
-                    const element = parser.nodeToElement(node);
-                    if (try getAttributeValue(element, "src")) |src| {
-                        try writeInline(state, "![", writer);
-                        if (try getAttributeValue(element, "alt")) |alt| {
-                            try writeInline(state, alt, writer);
-                        } else {
-                            try writeInline(state, src, writer);
-                        }
-                        try writeInline(state, "](", writer);
-                        // handle relative path
-                        if (src[0] == '/') {
-                            try writeInline(state, url.scheme(), writer);
-                            try writeInline(state, "://", writer);
-                            try writeInline(state, url.host(), writer);
-                        }
-                        try writeInline(state, src, writer);
-                        try writeInline(state, ")", writer);
-                    }
-                },
-                .ul => {
-                    var elem = Elem{ .parent = state.elem, .list_order = 0 };
-                    state.elem = &elem;
-                    defer state.elem = elem.parent;
-                    try ensureBlock(state, writer);
-                    try writeChildren(url, node, state, writer);
-                    try ensureBlock(state, writer);
-                },
-                .ol => {
-                    var elem = Elem{ .parent = state.elem, .list_order = 1 };
-                    state.elem = &elem;
-                    defer state.elem = elem.parent;
-                    try ensureBlock(state, writer);
-                    try writeChildren(url, node, state, writer);
-                    try ensureBlock(state, writer);
-                },
-                .li => blk: {
-                    const parent = state.elem orelse break :blk;
-                    const list_order = parent.list_order orelse break :blk;
-                    if (!state.block) try writer.writeAll("\n");
-                    if (list_order > 0) {
-                        // ordered list
-                        try writeInline(state, order[list_order - 1], writer);
-                        try writeInline(state, ". ", writer);
-                        parent.list_order = list_order + 1;
-                    } else {
-                        // unordered list
-                        try writeInline(state, "- ", writer);
-                    }
-                    try writeChildren(url, node, state, writer);
-                },
-                .input => {
-                    var elem = Elem{ .parent = state.elem, .inlin = true };
-                    state.elem = &elem;
-                    defer state.elem = elem.parent;
-                    const element = parser.nodeToElement(node);
-                    if (try getAttributeValue(element, "value")) |value| {
-                        try writeInline(state, value, writer);
-                        try writeInline(state, " ", writer);
-                    }
-                },
-
-                else => {
-                    try ensureBlock(state, writer);
-                    try writer.writeAll(@tagName(tag));
-                    try writer.writeAll(" not supported");
-                    try ensureBlock(state, writer);
-                },
-            }
-            // try writer.writeAll("\nend - ");
-            // try writer.writeAll(@tagName(tag));
-            // try writer.writeAll("\n");
-        },
-        .text => {
-            const v = try parser.nodeValue(node) orelse return;
-            const printed = try writeText(state, v, writer);
-            if (printed) state.block = false;
-        },
-        .cdata_section => {},
-        .comment => {},
-        // TODO handle processing instruction dump
-        .processing_instruction => {},
-        // document fragment is outside of the main document DOM, so we
-        // don't output it.
-        .document_fragment => {},
-        // document will never be called, but required for completeness.
-        .document => {},
-        // done globally instead, but required for completeness. Only the outer DOCTYPE should be written
-        .document_type => {},
-        // deprecated
-        .attribute, .entity_reference, .entity, .notation => {},
-    }
-}
-
-// TODO: not sure about + - . ! as they are very common characters
-// I fear that we add too much escape strings
-// TODO: | (pipe)
-const escape = [_]u8{ '\\', '`', '*', '_', '{', '}', '[', ']', '<', '>', '(', ')', '#' };
-
-fn writeText(state: *State, value: []const u8, writer: anytype) !bool {
-    if (value.len == 0) return false;
-
-    var last_char: u8 = ' ';
-    var printed: u64 = 0;
-    for (value, 0..) |v, i| {
-        // do not print:
-        // - multiple spaces
-        // - return line
-        // - tabs
-        if (v == last_char and v == ' ') continue;
-        if (v == '\n') continue;
-        if (v == '\t') continue;
-
-        // escape char
-        for (escape) |esc| {
-            if (v == esc) try writer.writeAll("\\");
-        }
-
-        if (printed == 0 and !state.is_inline()) {
-            if (state.last_char != '\n' and state.last_char != ' ') {
-                try writer.writeAll(" ");
-            }
-        }
-
-        last_char = v;
-        printed += 1;
-        const x = [_]u8{v}; // TODO: do we have something better?
-        try writer.writeAll(&x);
-        if (i == value.len - 1) state.last_char = v;
-    }
-    if (printed > 0) return true;
-    return false;
-}
-
-fn getAttributeValue(elem: *parser.Element, attr: []const u8) !?[]const u8 {
-    if (try parser.elementGetAttribute(elem, attr)) |value| {
-        if (value.len > 0) return value;
-    }
-    return null;
-}
-
-fn writeEscapedTextNode(writer: anytype, value: []const u8) !void {
-    var v = value;
-    while (v.len > 0) {
-        try writer.writeAll("TEXT: ");
-        const index = std.mem.indexOfAnyPos(u8, v, 0, &.{ '&', '<', '>' }) orelse {
-            return writer.writeAll(v);
-        };
-        try writer.writeAll(v[0..index]);
-        switch (v[index]) {
-            '&' => try writer.writeAll("&amp;"),
-            '<' => try writer.writeAll("&lt;"),
-            '>' => try writer.writeAll("&gt;"),
-            else => unreachable,
-        }
-        v = v[index + 1 ..];
-    }
-}

src/browser/mimalloc.zig

@@ -20,6 +20,7 @@
 // management.
 // We replace the libdom default usage of allocations with mimalloc heap
 // allocation to be able to free all memory used at once, like an arena usage.
+const std = @import("std");
 
 const c = @cImport({
     @cInclude("mimalloc.h");
@@ -33,43 +34,43 @@ const Error = error{
 var heap: ?*c.mi_heap_t = null;
 
 pub fn create() Error!void {
-    if (heap != null) return Error.HeapNotNull;
+    std.debug.assert(heap == null);
     heap = c.mi_heap_new();
-    if (heap == null) return Error.HeapNull;
+    std.debug.assert(heap != null);
 }
 
 pub fn destroy() void {
-    if (heap == null) return;
+    std.debug.assert(heap != null);
     c.mi_heap_destroy(heap.?);
     heap = null;
 }
 
-pub export fn m_alloc(size: usize) callconv(.C) ?*anyopaque {
-    if (heap == null) return null;
+pub export fn m_alloc(size: usize) callconv(.c) ?*anyopaque {
+    std.debug.assert(heap != null);
     return c.mi_heap_malloc(heap.?, size);
 }
 
-pub export fn re_alloc(ptr: ?*anyopaque, size: usize) callconv(.C) ?*anyopaque {
-    if (heap == null) return null;
+pub export fn re_alloc(ptr: ?*anyopaque, size: usize) callconv(.c) ?*anyopaque {
+    std.debug.assert(heap != null);
     return c.mi_heap_realloc(heap.?, ptr, size);
 }
 
-pub export fn c_alloc(nmemb: usize, size: usize) callconv(.C) ?*anyopaque {
-    if (heap == null) return null;
+pub export fn c_alloc(nmemb: usize, size: usize) callconv(.c) ?*anyopaque {
+    std.debug.assert(heap != null);
     return c.mi_heap_calloc(heap.?, nmemb, size);
 }
 
-pub export fn str_dup(s: [*c]const u8) callconv(.C) [*c]u8 {
-    if (heap == null) return null;
+pub export fn str_dup(s: [*c]const u8) callconv(.c) [*c]u8 {
+    std.debug.assert(heap != null);
     return c.mi_heap_strdup(heap.?, s);
 }
 
-pub export fn strn_dup(s: [*c]const u8, size: usize) callconv(.C) [*c]u8 {
-    if (heap == null) return null;
+pub export fn strn_dup(s: [*c]const u8, size: usize) callconv(.c) [*c]u8 {
+    std.debug.assert(heap != null);
     return c.mi_heap_strndup(heap.?, s, size);
 }
 
 // NOOP, use destroy to clear all the memory allocated at once.
-pub export fn f_ree(_: ?*anyopaque) callconv(.C) void {
+pub export fn f_ree(_: ?*anyopaque) callconv(.c) void {
     return;
 }

src/browser/mime.zig

@@ -22,11 +22,11 @@ const Allocator = std.mem.Allocator;
 pub const Mime = struct {
     content_type: ContentType,
     params: []const u8 = "",
-    charset: ?[]const u8 = null,
+    charset: ?[:0]const u8 = null,
 
     pub const unknown = Mime{
         .params = "",
-        .charset = "",
+        .charset = null,
         .content_type = .{ .unknown = {} },
     };
 
@@ -35,6 +35,8 @@ pub const Mime = struct {
         text_html,
         text_javascript,
         text_plain,
+        text_css,
+        application_json,
         unknown,
         other,
     };
@@ -44,11 +46,13 @@ pub const Mime = struct {
         text_html: void,
         text_javascript: void,
         text_plain: void,
+        text_css: void,
+        application_json: void,
         unknown: void,
         other: struct { type: []const u8, sub_type: []const u8 },
     };
 
-    pub fn parse(arena: Allocator, input: []u8) !Mime {
+    pub fn parse(input: []u8) !Mime {
         if (input.len > 255) {
             return error.TooBig;
         }
@@ -65,7 +69,7 @@ pub const Mime = struct {
 
         const params = trimLeft(normalized[type_len..]);
 
-        var charset: ?[]const u8 = null;
+        var charset: ?[:0]const u8 = null;
 
         var it = std.mem.splitScalar(u8, params, ';');
         while (it.next()) |attr| {
@@ -82,7 +86,37 @@ pub const Mime = struct {
             }, name) orelse continue;
 
             switch (attribute_name) {
-                .charset => charset = try parseAttributeValue(arena, value),
+                .charset => {
+                    // We used to have a proper value parser, but we currently
+                    // only care about the charset attribute, plus only about
+                    // the UTF-8 value. It's a lot easier to do it this way,
+                    // and it doesn't require an allocation to (a) unescape the
+                    // value or (b) ensure the correct lifetime.
+                    if (value.len == 0) {
+                        break;
+                    }
+                    var attribute_value = value;
+                    if (value[0] == '"') {
+                        if (value.len < 3 or value[value.len - 1] != '"') {
+                            return error.Invalid;
+                        }
+                        attribute_value = value[1 .. value.len - 1];
+                    }
+
+                    if (std.ascii.eqlIgnoreCase(attribute_value, "utf-8")) {
+                        charset = "UTF-8";
+                    } else if (std.ascii.eqlIgnoreCase(attribute_value, "iso-8859-1")) {
+                        charset = "ISO-8859-1";
+                    } else {
+                        // we only care about null (which we default to UTF-8)
+                        // or UTF-8. If this is actually set (i.e. not null)
+                        // and isn't UTF-8, we'll just put a dummy value. If
+                        // we want to capture the actual value, we'll need to
+                        // dupe/allocate it. Since, for now, we don't need that
+                        // we can avoid the allocation.
+                        charset = "lightpanda:UNSUPPORTED";
+                    }
+                },
             }
         }
 
@@ -174,18 +208,22 @@ pub const Mime = struct {
         if (std.meta.stringToEnum(enum {
             @"text/xml",
             @"text/html",
+            @"text/css",
+            @"text/plain",
 
             @"text/javascript",
             @"application/javascript",
             @"application/x-javascript",
 
-            @"text/plain",
+            @"application/json",
         }, type_name)) |known_type| {
             const ct: ContentType = switch (known_type) {
                 .@"text/xml" => .{ .text_xml = {} },
                 .@"text/html" => .{ .text_html = {} },
                 .@"text/javascript", .@"application/javascript", .@"application/x-javascript" => .{ .text_javascript = {} },
                 .@"text/plain" => .{ .text_plain = {} },
+                .@"text/css" => .{ .text_css = {} },
+                .@"application/json" => .{ .application_json = {} },
             };
             return .{ ct, attribute_start };
         }
@@ -216,56 +254,6 @@ pub const Mime = struct {
         break :blk v;
     };
 
-    fn parseAttributeValue(arena: Allocator, value: []const u8) ![]const u8 {
-        if (value[0] != '"') {
-            return value;
-        }
-
-        // 1 to skip the opening quote
-        var value_pos: usize = 1;
-        var unescaped_len: usize = 0;
-        const last = value.len - 1;
-
-        while (value_pos < value.len) {
-            switch (value[value_pos]) {
-                '"' => break,
-                '\\' => {
-                    if (value_pos == last) {
-                        return error.Invalid;
-                    }
-                    const next = value[value_pos + 1];
-                    if (T_SPECIAL[next] == false) {
-                        return error.Invalid;
-                    }
-                    value_pos += 2;
-                },
-                else => value_pos += 1,
-            }
-            unescaped_len += 1;
-        }
-
-        if (unescaped_len == 0) {
-            return error.Invalid;
-        }
-
-        value_pos = 1;
-        const owned = try arena.alloc(u8, unescaped_len);
-        for (0..unescaped_len) |i| {
-            switch (value[value_pos]) {
-                '"' => break,
-                '\\' => {
-                    owned[i] = value[value_pos + 1];
-                    value_pos += 2;
-                },
-                else => |c| {
-                    owned[i] = c;
-                    value_pos += 1;
-                },
-            }
-        }
-        return owned;
-    }
-
     const VALID_CODEPOINTS = blk: {
         var v: [256]bool = undefined;
         for (0..256) |i| {
@@ -296,7 +284,7 @@ pub const Mime = struct {
 };
 
 const testing = @import("../testing.zig");
-test "Mime: invalid " {
+test "Mime: invalid" {
     defer testing.reset();
 
     const invalids = [_][]const u8{
@@ -314,12 +302,11 @@ test "Mime: invalid " {
         "text/html; charset=\"\"",
         "text/html; charset=\"",
         "text/html; charset=\"\\",
-        "text/html; charset=\"\\a\"", // invalid to escape non special characters
     };
 
     for (invalids) |invalid| {
         const mutable_input = try testing.arena_allocator.dupe(u8, invalid);
-        try testing.expectError(error.Invalid, Mime.parse(undefined, mutable_input));
+        try testing.expectError(error.Invalid, Mime.parse(mutable_input));
     }
 }
 
@@ -349,6 +336,9 @@ test "Mime: parse common" {
     try expect(.{ .content_type = .{ .text_javascript = {} } }, "text/javascript");
     try expect(.{ .content_type = .{ .text_javascript = {} } }, "Application/JavaScript");
     try expect(.{ .content_type = .{ .text_javascript = {} } }, "application/x-javascript");
+
+    try expect(.{ .content_type = .{ .application_json = {} } }, "application/json");
+    try expect(.{ .content_type = .{ .text_css = {} } }, "text/css");
 }
 
 test "Mime: parse uncommon" {
@@ -373,19 +363,19 @@ test "Mime: parse charset" {
 
     try expect(.{
         .content_type = .{ .text_xml = {} },
-        .charset = "utf-8",
+        .charset = "UTF-8",
         .params = "charset=utf-8",
     }, "text/xml; charset=utf-8");
 
     try expect(.{
         .content_type = .{ .text_xml = {} },
-        .charset = "utf-8",
+        .charset = "UTF-8",
         .params = "charset=\"utf-8\"",
     }, "text/xml;charset=\"utf-8\"");
 
     try expect(.{
         .content_type = .{ .text_xml = {} },
-        .charset = "\\ \" ",
+        .charset = "lightpanda:UNSUPPORTED",
         .params = "charset=\"\\\\ \\\" \"",
     }, "text/xml;charset=\"\\\\ \\\" \"   ");
 }
@@ -396,7 +386,7 @@ test "Mime: isHTML" {
     const isHTML = struct {
         fn isHTML(expected: bool, input: []const u8) !void {
             const mutable_input = try testing.arena_allocator.dupe(u8, input);
-            var mime = try Mime.parse(testing.arena_allocator, mutable_input);
+            var mime = try Mime.parse(mutable_input);
             try testing.expectEqual(expected, mime.isHTML());
         }
     }.isHTML;
@@ -482,7 +472,7 @@ const Expectation = struct {
 fn expect(expected: Expectation, input: []const u8) !void {
     const mutable_input = try testing.arena_allocator.dupe(u8, input);
 
-    const actual = try Mime.parse(testing.arena_allocator, mutable_input);
+    const actual = try Mime.parse(mutable_input);
     try testing.expectEqual(
         std.meta.activeTag(expected.content_type),
         std.meta.activeTag(actual.content_type),

src/browser/polyfill/fetch.zig

@@ -16,8 +16,6 @@ test "Browser.fetch" {
     var runner = try testing.jsRunner(testing.tracking_allocator, .{});
     defer runner.deinit();
 
-    try @import("polyfill.zig").load(testing.allocator, runner.page.main_context);
-
     try runner.testCases(&.{
         .{
             \\  var ok = false;

src/browser/polyfill/polyfill.zig

@@ -23,25 +23,98 @@ const log = @import("../../log.zig");
 const Allocator = std.mem.Allocator;
 const Env = @import("../env.zig").Env;
 
-const modules = [_]struct {
-    name: []const u8,
-    source: []const u8,
-}{
-    .{ .name = "polyfill-fetch", .source = @import("fetch.zig").source },
+pub const Loader = struct {
+    state: enum { empty, loading } = .empty,
+
+    done: struct {
+        fetch: bool = false,
+        webcomponents: bool = false,
+    } = .{},
+
+    fn load(self: *Loader, comptime name: []const u8, source: []const u8, js_context: *Env.JsContext) void {
+        var try_catch: Env.TryCatch = undefined;
+        try_catch.init(js_context);
+        defer try_catch.deinit();
+
+        self.state = .loading;
+        defer self.state = .empty;
+
+        log.debug(.js, "polyfill load", .{ .name = name });
+        _ = js_context.exec(source, name) catch |err| {
+            log.fatal(.app, "polyfill error", .{
+                .name = name,
+                .err = try_catch.err(js_context.call_arena) catch @errorName(err) orelse @errorName(err),
+            });
+        };
+
+        @field(self.done, name) = true;
+    }
+
+    pub fn missing(self: *Loader, name: []const u8, js_context: *Env.JsContext) bool {
+        // Avoid recursive calls during polyfill loading.
+        if (self.state == .loading) {
+            return false;
+        }
+
+        if (!self.done.fetch and isFetch(name)) {
+            const source = @import("fetch.zig").source;
+            self.load("fetch", source, js_context);
+
+            // We return false here: We want v8 to continue the calling chain
+            // to finally find the polyfill we just inserted. If we want to
+            // return false and stops the call chain, we have to use
+            // `info.GetReturnValue.Set()` function, or `undefined` will be
+            // returned immediately.
+            return false;
+        }
+
+        if (!self.done.webcomponents and isWebcomponents(name)) {
+            const source = @import("webcomponents.zig").source;
+            self.load("webcomponents", source, js_context);
+            // We return false here: We want v8 to continue the calling chain
+            // to finally find the polyfill we just inserted. If we want to
+            // return false and stops the call chain, we have to use
+            // `info.GetReturnValue.Set()` function, or `undefined` will be
+            // returned immediately.
+            return false;
+        }
+
+        if (comptime builtin.mode == .Debug) {
+            log.debug(.unknown_prop, "unkown global property", .{
+                .info = "but the property can exist in pure JS",
+                .property = name,
+            });
+        }
+
+        return false;
+    }
+
+    fn isFetch(name: []const u8) bool {
+        if (std.mem.eql(u8, name, "fetch")) return true;
+        if (std.mem.eql(u8, name, "Request")) return true;
+        if (std.mem.eql(u8, name, "Response")) return true;
+        if (std.mem.eql(u8, name, "Headers")) return true;
+        return false;
+    }
+
+    fn isWebcomponents(name: []const u8) bool {
+        if (std.mem.eql(u8, name, "customElements")) return true;
+        return false;
+    }
 };
 
-pub fn load(allocator: Allocator, js_context: *Env.JsContext) !void {
+pub fn preload(allocator: Allocator, js_context: *Env.JsContext) !void {
     var try_catch: Env.TryCatch = undefined;
     try_catch.init(js_context);
     defer try_catch.deinit();
 
-    for (modules) |m| {
-        _ = js_context.exec(m.source, m.name) catch |err| {
-            if (try try_catch.err(allocator)) |msg| {
-                defer allocator.free(msg);
-                log.fatal(.app, "polyfill error", .{ .name = m.name, .err = msg });
-            }
-            return err;
-        };
-    }
+    const name = "webcomponents-pre";
+    const source = @import("webcomponents.zig").pre;
+    _ = js_context.exec(source, name) catch |err| {
+        if (try try_catch.err(allocator)) |msg| {
+            defer allocator.free(msg);
+            log.fatal(.app, "polyfill error", .{ .name = name, .err = msg });
+        }
+        return err;
+    };
 }

src/browser/polyfill/webcomponents.js

@@ -0,0 +1,61 @@
+/**
+@license @nocompile
+Copyright (c) 2018 The Polymer Project Authors. All rights reserved.
+This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
+The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
+The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
+Code distributed by Google as part of the polymer project is also
+subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
+*/
+(function(){/*
+
+ Copyright (c) 2016 The Polymer Project Authors. All rights reserved.
+ This code may only be used under the BSD style license found at
+ http://polymer.github.io/LICENSE.txt The complete set of authors may be found
+ at http://polymer.github.io/AUTHORS.txt The complete set of contributors may
+ be found at http://polymer.github.io/CONTRIBUTORS.txt Code distributed by
+ Google as part of the polymer project is also subject to an additional IP
+ rights grant found at http://polymer.github.io/PATENTS.txt
+*/
+'use strict';var n=window.Document.prototype.createElement,p=window.Document.prototype.createElementNS,aa=window.Document.prototype.importNode,ba=window.Document.prototype.prepend,ca=window.Document.prototype.append,da=window.DocumentFragment.prototype.prepend,ea=window.DocumentFragment.prototype.append,q=window.Node.prototype.cloneNode,r=window.Node.prototype.appendChild,t=window.Node.prototype.insertBefore,u=window.Node.prototype.removeChild,v=window.Node.prototype.replaceChild,w=Object.getOwnPropertyDescriptor(window.Node.prototype,
+"textContent"),y=window.Element.prototype.attachShadow,z=Object.getOwnPropertyDescriptor(window.Element.prototype,"innerHTML"),A=window.Element.prototype.getAttribute,B=window.Element.prototype.setAttribute,C=window.Element.prototype.removeAttribute,D=window.Element.prototype.toggleAttribute,E=window.Element.prototype.getAttributeNS,F=window.Element.prototype.setAttributeNS,G=window.Element.prototype.removeAttributeNS,H=window.Element.prototype.insertAdjacentElement,fa=window.Element.prototype.insertAdjacentHTML,
+ha=window.Element.prototype.prepend,ia=window.Element.prototype.append,ja=window.Element.prototype.before,ka=window.Element.prototype.after,la=window.Element.prototype.replaceWith,ma=window.Element.prototype.remove,na=window.HTMLElement,I=Object.getOwnPropertyDescriptor(window.HTMLElement.prototype,"innerHTML"),oa=window.HTMLElement.prototype.insertAdjacentElement,pa=window.HTMLElement.prototype.insertAdjacentHTML;var qa=new Set;"annotation-xml color-profile font-face font-face-src font-face-uri font-face-format font-face-name missing-glyph".split(" ").forEach(function(a){return qa.add(a)});function ra(a){var b=qa.has(a);a=/^[a-z][.0-9_a-z]*-[-.0-9_a-z]*$/.test(a);return!b&&a}var sa=document.contains?document.contains.bind(document):document.documentElement.contains.bind(document.documentElement);
+function J(a){var b=a.isConnected;if(void 0!==b)return b;if(sa(a))return!0;for(;a&&!(a.__CE_isImportDocument||a instanceof Document);)a=a.parentNode||(window.ShadowRoot&&a instanceof ShadowRoot?a.host:void 0);return!(!a||!(a.__CE_isImportDocument||a instanceof Document))}function K(a){var b=a.children;if(b)return Array.prototype.slice.call(b);b=[];for(a=a.firstChild;a;a=a.nextSibling)a.nodeType===Node.ELEMENT_NODE&&b.push(a);return b}
+function L(a,b){for(;b&&b!==a&&!b.nextSibling;)b=b.parentNode;return b&&b!==a?b.nextSibling:null}
+function M(a,b,d){for(var f=a;f;){if(f.nodeType===Node.ELEMENT_NODE){var c=f;b(c);var e=c.localName;if("link"===e&&"import"===c.getAttribute("rel")){f=c.import;void 0===d&&(d=new Set);if(f instanceof Node&&!d.has(f))for(d.add(f),f=f.firstChild;f;f=f.nextSibling)M(f,b,d);f=L(a,c);continue}else if("template"===e){f=L(a,c);continue}if(c=c.__CE_shadowRoot)for(c=c.firstChild;c;c=c.nextSibling)M(c,b,d)}f=f.firstChild?f.firstChild:L(a,f)}};function N(){var a=!(null===O||void 0===O||!O.noDocumentConstructionObserver),b=!(null===O||void 0===O||!O.shadyDomFastWalk);this.m=[];this.g=[];this.j=!1;this.shadyDomFastWalk=b;this.I=!a}function P(a,b,d,f){var c=window.ShadyDOM;if(a.shadyDomFastWalk&&c&&c.inUse){if(b.nodeType===Node.ELEMENT_NODE&&d(b),b.querySelectorAll)for(a=c.nativeMethods.querySelectorAll.call(b,"*"),b=0;b<a.length;b++)d(a[b])}else M(b,d,f)}function ta(a,b){a.j=!0;a.m.push(b)}function ua(a,b){a.j=!0;a.g.push(b)}
+function Q(a,b){a.j&&P(a,b,function(d){return R(a,d)})}function R(a,b){if(a.j&&!b.__CE_patched){b.__CE_patched=!0;for(var d=0;d<a.m.length;d++)a.m[d](b);for(d=0;d<a.g.length;d++)a.g[d](b)}}function S(a,b){var d=[];P(a,b,function(c){return d.push(c)});for(b=0;b<d.length;b++){var f=d[b];1===f.__CE_state?a.connectedCallback(f):T(a,f)}}function U(a,b){var d=[];P(a,b,function(c){return d.push(c)});for(b=0;b<d.length;b++){var f=d[b];1===f.__CE_state&&a.disconnectedCallback(f)}}
+function V(a,b,d){d=void 0===d?{}:d;var f=d.J,c=d.upgrade||function(g){return T(a,g)},e=[];P(a,b,function(g){a.j&&R(a,g);if("link"===g.localName&&"import"===g.getAttribute("rel")){var h=g.import;h instanceof Node&&(h.__CE_isImportDocument=!0,h.__CE_registry=document.__CE_registry);h&&"complete"===h.readyState?h.__CE_documentLoadHandled=!0:g.addEventListener("load",function(){var k=g.import;if(!k.__CE_documentLoadHandled){k.__CE_documentLoadHandled=!0;var l=new Set;f&&(f.forEach(function(m){return l.add(m)}),
+l.delete(k));V(a,k,{J:l,upgrade:c})}})}else e.push(g)},f);for(b=0;b<e.length;b++)c(e[b])}
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+for(c=0;c<e.length;c++){var g=e[c],h=b.getAttribute(g);null!==h&&a.attributeChangedCallback(b,g,null,h,null)}}J(b)&&a.connectedCallback(b)}}catch(k){X(k)}}N.prototype.connectedCallback=function(a){var b=a.__CE_definition;if(b.connectedCallback)try{b.connectedCallback.call(a)}catch(d){X(d)}};N.prototype.disconnectedCallback=function(a){var b=a.__CE_definition;if(b.disconnectedCallback)try{b.disconnectedCallback.call(a)}catch(d){X(d)}};
+N.prototype.attributeChangedCallback=function(a,b,d,f,c){var e=a.__CE_definition;if(e.attributeChangedCallback&&-1<e.observedAttributes.indexOf(b))try{e.attributeChangedCallback.call(a,b,d,f,c)}catch(g){X(g)}};
+function va(a,b,d,f){var c=b.__CE_registry;if(c&&(null===f||"http://www.w3.org/1999/xhtml"===f)&&(c=W(c,d)))try{var e=new c.constructorFunction;if(void 0===e.__CE_state||void 0===e.__CE_definition)throw Error("Failed to construct '"+d+"': The returned value was not constructed with the HTMLElement constructor.");if("http://www.w3.org/1999/xhtml"!==e.namespaceURI)throw Error("Failed to construct '"+d+"': The constructed element's namespace must be the HTML namespace.");if(e.hasAttributes())throw Error("Failed to construct '"+
+d+"': The constructed element must not have any attributes.");if(null!==e.firstChild)throw Error("Failed to construct '"+d+"': The constructed element must not have any children.");if(null!==e.parentNode)throw Error("Failed to construct '"+d+"': The constructed element must not have a parent node.");if(e.ownerDocument!==b)throw Error("Failed to construct '"+d+"': The constructed element's owner document is incorrect.");if(e.localName!==d)throw Error("Failed to construct '"+d+"': The constructed element's local name is incorrect.");
+return e}catch(g){return X(g),b=null===f?n.call(b,d):p.call(b,f,d),Object.setPrototypeOf(b,HTMLUnknownElement.prototype),b.__CE_state=2,b.__CE_definition=void 0,R(a,b),b}b=null===f?n.call(b,d):p.call(b,f,d);R(a,b);return b}
+function X(a){var b="",d="",f=0,c=0;a instanceof Error?(b=a.message,d=a.sourceURL||a.fileName||"",f=a.line||a.lineNumber||0,c=a.column||a.columnNumber||0):b="Uncaught "+String(a);var e=void 0;void 0===ErrorEvent.prototype.initErrorEvent?e=new ErrorEvent("error",{cancelable:!0,message:b,filename:d,lineno:f,colno:c,error:a}):(e=document.createEvent("ErrorEvent"),e.initErrorEvent("error",!1,!0,b,d,f),e.preventDefault=function(){Object.defineProperty(this,"defaultPrevented",{configurable:!0,get:function(){return!0}})});
+void 0===e.error&&Object.defineProperty(e,"error",{configurable:!0,enumerable:!0,get:function(){return a}});window.dispatchEvent(e);e.defaultPrevented||console.error(a)};function wa(){var a=this;this.g=void 0;this.F=new Promise(function(b){a.l=b})}wa.prototype.resolve=function(a){if(this.g)throw Error("Already resolved.");this.g=a;this.l(a)};function xa(a){var b=document;this.l=void 0;this.h=a;this.g=b;V(this.h,this.g);"loading"===this.g.readyState&&(this.l=new MutationObserver(this.G.bind(this)),this.l.observe(this.g,{childList:!0,subtree:!0}))}function ya(a){a.l&&a.l.disconnect()}xa.prototype.G=function(a){var b=this.g.readyState;"interactive"!==b&&"complete"!==b||ya(this);for(b=0;b<a.length;b++)for(var d=a[b].addedNodes,f=0;f<d.length;f++)V(this.h,d[f])};function Y(a){this.s=new Map;this.u=new Map;this.C=new Map;this.A=!1;this.B=new Map;this.o=function(b){return b()};this.i=!1;this.v=[];this.h=a;this.D=a.I?new xa(a):void 0}Y.prototype.H=function(a,b){var d=this;if(!(b instanceof Function))throw new TypeError("Custom element constructor getters must be functions.");za(this,a);this.s.set(a,b);this.v.push(a);this.i||(this.i=!0,this.o(function(){return Aa(d)}))};
+Y.prototype.define=function(a,b){var d=this;if(!(b instanceof Function))throw new TypeError("Custom element constructors must be functions.");za(this,a);Ba(this,a,b);this.v.push(a);this.i||(this.i=!0,this.o(function(){return Aa(d)}))};function za(a,b){if(!ra(b))throw new SyntaxError("The element name '"+b+"' is not valid.");if(W(a,b))throw Error("A custom element with name '"+(b+"' has already been defined."));if(a.A)throw Error("A custom element is already being defined.");}
+function Ba(a,b,d){a.A=!0;var f;try{var c=d.prototype;if(!(c instanceof Object))throw new TypeError("The custom element constructor's prototype is not an object.");var e=function(m){var x=c[m];if(void 0!==x&&!(x instanceof Function))throw Error("The '"+m+"' callback must be a function.");return x};var g=e("connectedCallback");var h=e("disconnectedCallback");var k=e("adoptedCallback");var l=(f=e("attributeChangedCallback"))&&d.observedAttributes||[]}catch(m){throw m;}finally{a.A=!1}d={localName:b,
+constructorFunction:d,connectedCallback:g,disconnectedCallback:h,adoptedCallback:k,attributeChangedCallback:f,observedAttributes:l,constructionStack:[]};a.u.set(b,d);a.C.set(d.constructorFunction,d);return d}Y.prototype.upgrade=function(a){V(this.h,a)};
+function Aa(a){if(!1!==a.i){a.i=!1;for(var b=[],d=a.v,f=new Map,c=0;c<d.length;c++)f.set(d[c],[]);V(a.h,document,{upgrade:function(k){if(void 0===k.__CE_state){var l=k.localName,m=f.get(l);m?m.push(k):a.u.has(l)&&b.push(k)}}});for(c=0;c<b.length;c++)T(a.h,b[c]);for(c=0;c<d.length;c++){for(var e=d[c],g=f.get(e),h=0;h<g.length;h++)T(a.h,g[h]);(e=a.B.get(e))&&e.resolve(void 0)}d.length=0}}Y.prototype.get=function(a){if(a=W(this,a))return a.constructorFunction};
+Y.prototype.whenDefined=function(a){if(!ra(a))return Promise.reject(new SyntaxError("'"+a+"' is not a valid custom element name."));var b=this.B.get(a);if(b)return b.F;b=new wa;this.B.set(a,b);var d=this.u.has(a)||this.s.has(a);a=-1===this.v.indexOf(a);d&&a&&b.resolve(void 0);return b.F};Y.prototype.polyfillWrapFlushCallback=function(a){this.D&&ya(this.D);var b=this.o;this.o=function(d){return a(function(){return b(d)})}};
+function W(a,b){var d=a.u.get(b);if(d)return d;if(d=a.s.get(b)){a.s.delete(b);try{return Ba(a,b,d())}catch(f){X(f)}}}Y.prototype.define=Y.prototype.define;Y.prototype.upgrade=Y.prototype.upgrade;Y.prototype.get=Y.prototype.get;Y.prototype.whenDefined=Y.prototype.whenDefined;Y.prototype.polyfillDefineLazy=Y.prototype.H;Y.prototype.polyfillWrapFlushCallback=Y.prototype.polyfillWrapFlushCallback;function Z(a,b,d){function f(c){return function(e){for(var g=[],h=0;h<arguments.length;++h)g[h]=arguments[h];h=[];for(var k=[],l=0;l<g.length;l++){var m=g[l];m instanceof Element&&J(m)&&k.push(m);if(m instanceof DocumentFragment)for(m=m.firstChild;m;m=m.nextSibling)h.push(m);else h.push(m)}c.apply(this,g);for(g=0;g<k.length;g++)U(a,k[g]);if(J(this))for(g=0;g<h.length;g++)k=h[g],k instanceof Element&&S(a,k)}}void 0!==d.prepend&&(b.prepend=f(d.prepend));void 0!==d.append&&(b.append=f(d.append))};function Ca(a){Document.prototype.createElement=function(b){return va(a,this,b,null)};Document.prototype.importNode=function(b,d){b=aa.call(this,b,!!d);this.__CE_registry?V(a,b):Q(a,b);return b};Document.prototype.createElementNS=function(b,d){return va(a,this,d,b)};Z(a,Document.prototype,{prepend:ba,append:ca})};function Da(a){function b(f){return function(c){for(var e=[],g=0;g<arguments.length;++g)e[g]=arguments[g];g=[];for(var h=[],k=0;k<e.length;k++){var l=e[k];l instanceof Element&&J(l)&&h.push(l);if(l instanceof DocumentFragment)for(l=l.firstChild;l;l=l.nextSibling)g.push(l);else g.push(l)}f.apply(this,e);for(e=0;e<h.length;e++)U(a,h[e]);if(J(this))for(e=0;e<g.length;e++)h=g[e],h instanceof Element&&S(a,h)}}var d=Element.prototype;void 0!==ja&&(d.before=b(ja));void 0!==ka&&(d.after=b(ka));void 0!==la&&
+(d.replaceWith=function(f){for(var c=[],e=0;e<arguments.length;++e)c[e]=arguments[e];e=[];for(var g=[],h=0;h<c.length;h++){var k=c[h];k instanceof Element&&J(k)&&g.push(k);if(k instanceof DocumentFragment)for(k=k.firstChild;k;k=k.nextSibling)e.push(k);else e.push(k)}h=J(this);la.apply(this,c);for(c=0;c<g.length;c++)U(a,g[c]);if(h)for(U(a,this),c=0;c<e.length;c++)g=e[c],g instanceof Element&&S(a,g)});void 0!==ma&&(d.remove=function(){var f=J(this);ma.call(this);f&&U(a,this)})};function Ea(a){function b(c,e){Object.defineProperty(c,"innerHTML",{enumerable:e.enumerable,configurable:!0,get:e.get,set:function(g){var h=this,k=void 0;J(this)&&(k=[],P(a,this,function(x){x!==h&&k.push(x)}));e.set.call(this,g);if(k)for(var l=0;l<k.length;l++){var m=k[l];1===m.__CE_state&&a.disconnectedCallback(m)}this.ownerDocument.__CE_registry?V(a,this):Q(a,this);return g}})}function d(c,e){c.insertAdjacentElement=function(g,h){var k=J(h);g=e.call(this,g,h);k&&U(a,h);J(g)&&S(a,h);return g}}function f(c,
+e){function g(h,k){for(var l=[];h!==k;h=h.nextSibling)l.push(h);for(k=0;k<l.length;k++)V(a,l[k])}c.insertAdjacentHTML=function(h,k){h=h.toLowerCase();if("beforebegin"===h){var l=this.previousSibling;e.call(this,h,k);g(l||this.parentNode.firstChild,this)}else if("afterbegin"===h)l=this.firstChild,e.call(this,h,k),g(this.firstChild,l);else if("beforeend"===h)l=this.lastChild,e.call(this,h,k),g(l||this.firstChild,null);else if("afterend"===h)l=this.nextSibling,e.call(this,h,k),g(this.nextSibling,l);
+else throw new SyntaxError("The value provided ("+String(h)+") is not one of 'beforebegin', 'afterbegin', 'beforeend', or 'afterend'.");}}y&&(Element.prototype.attachShadow=function(c){c=y.call(this,c);if(a.j&&!c.__CE_patched){c.__CE_patched=!0;for(var e=0;e<a.m.length;e++)a.m[e](c)}return this.__CE_shadowRoot=c});z&&z.get?b(Element.prototype,z):I&&I.get?b(HTMLElement.prototype,I):ua(a,function(c){b(c,{enumerable:!0,configurable:!0,get:function(){return q.call(this,!0).innerHTML},set:function(e){var g=
+"template"===this.localName,h=g?this.content:this,k=p.call(document,this.namespaceURI,this.localName);for(k.innerHTML=e;0<h.childNodes.length;)u.call(h,h.childNodes[0]);for(e=g?k.content:k;0<e.childNodes.length;)r.call(h,e.childNodes[0])}})});Element.prototype.setAttribute=function(c,e){if(1!==this.__CE_state)return B.call(this,c,e);var g=A.call(this,c);B.call(this,c,e);e=A.call(this,c);a.attributeChangedCallback(this,c,g,e,null)};Element.prototype.setAttributeNS=function(c,e,g){if(1!==this.__CE_state)return F.call(this,
+c,e,g);var h=E.call(this,c,e);F.call(this,c,e,g);g=E.call(this,c,e);a.attributeChangedCallback(this,e,h,g,c)};Element.prototype.removeAttribute=function(c){if(1!==this.__CE_state)return C.call(this,c);var e=A.call(this,c);C.call(this,c);null!==e&&a.attributeChangedCallback(this,c,e,null,null)};D&&(Element.prototype.toggleAttribute=function(c,e){if(1!==this.__CE_state)return D.call(this,c,e);var g=A.call(this,c),h=null!==g;e=D.call(this,c,e);h!==e&&a.attributeChangedCallback(this,c,g,e?"":null,null);
+return e});Element.prototype.removeAttributeNS=function(c,e){if(1!==this.__CE_state)return G.call(this,c,e);var g=E.call(this,c,e);G.call(this,c,e);var h=E.call(this,c,e);g!==h&&a.attributeChangedCallback(this,e,g,h,c)};oa?d(HTMLElement.prototype,oa):H&&d(Element.prototype,H);pa?f(HTMLElement.prototype,pa):fa&&f(Element.prototype,fa);Z(a,Element.prototype,{prepend:ha,append:ia});Da(a)};var Fa={};function Ga(a){function b(){var d=this.constructor;var f=document.__CE_registry.C.get(d);if(!f)throw Error("Failed to construct a custom element: The constructor was not registered with `customElements`.");var c=f.constructionStack;if(0===c.length)return c=n.call(document,f.localName),Object.setPrototypeOf(c,d.prototype),c.__CE_state=1,c.__CE_definition=f,R(a,c),c;var e=c.length-1,g=c[e];if(g===Fa)throw Error("Failed to construct '"+f.localName+"': This element was already constructed.");c[e]=Fa;
+Object.setPrototypeOf(g,d.prototype);R(a,g);return g}b.prototype=na.prototype;Object.defineProperty(HTMLElement.prototype,"constructor",{writable:!0,configurable:!0,enumerable:!1,value:b});window.HTMLElement=b};function Ha(a){function b(d,f){Object.defineProperty(d,"textContent",{enumerable:f.enumerable,configurable:!0,get:f.get,set:function(c){if(this.nodeType===Node.TEXT_NODE)f.set.call(this,c);else{var e=void 0;if(this.firstChild){var g=this.childNodes,h=g.length;if(0<h&&J(this)){e=Array(h);for(var k=0;k<h;k++)e[k]=g[k]}}f.set.call(this,c);if(e)for(c=0;c<e.length;c++)U(a,e[c])}}})}Node.prototype.insertBefore=function(d,f){if(d instanceof DocumentFragment){var c=K(d);d=t.call(this,d,f);if(J(this))for(f=
+0;f<c.length;f++)S(a,c[f]);return d}c=d instanceof Element&&J(d);f=t.call(this,d,f);c&&U(a,d);J(this)&&S(a,d);return f};Node.prototype.appendChild=function(d){if(d instanceof DocumentFragment){var f=K(d);d=r.call(this,d);if(J(this))for(var c=0;c<f.length;c++)S(a,f[c]);return d}f=d instanceof Element&&J(d);c=r.call(this,d);f&&U(a,d);J(this)&&S(a,d);return c};Node.prototype.cloneNode=function(d){d=q.call(this,!!d);this.ownerDocument.__CE_registry?V(a,d):Q(a,d);return d};Node.prototype.removeChild=function(d){var f=
+d instanceof Element&&J(d),c=u.call(this,d);f&&U(a,d);return c};Node.prototype.replaceChild=function(d,f){if(d instanceof DocumentFragment){var c=K(d);d=v.call(this,d,f);if(J(this))for(U(a,f),f=0;f<c.length;f++)S(a,c[f]);return d}c=d instanceof Element&&J(d);var e=v.call(this,d,f),g=J(this);g&&U(a,f);c&&U(a,d);g&&S(a,d);return e};w&&w.get?b(Node.prototype,w):ta(a,function(d){b(d,{enumerable:!0,configurable:!0,get:function(){for(var f=[],c=this.firstChild;c;c=c.nextSibling)c.nodeType!==Node.COMMENT_NODE&&
+f.push(c.textContent);return f.join("")},set:function(f){for(;this.firstChild;)u.call(this,this.firstChild);null!=f&&""!==f&&r.call(this,document.createTextNode(f))}})})};var O=window.customElements;function Ia(){var a=new N;Ga(a);Ca(a);Z(a,DocumentFragment.prototype,{prepend:da,append:ea});Ha(a);Ea(a);window.CustomElementRegistry=Y;a=new Y(a);document.__CE_registry=a;Object.defineProperty(window,"customElements",{configurable:!0,enumerable:!0,value:a})}O&&!O.forcePolyfill&&"function"==typeof O.define&&"function"==typeof O.get||Ia();window.__CE_installPolyfill=Ia;/*
+
+Copyright (c) 2017 The Polymer Project Authors. All rights reserved.
+This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
+The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
+The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
+Code distributed by Google as part of the polymer project is also
+subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
+*/
+}).call(this);

src/browser/polyfill/webcomponents.zig

@@ -0,0 +1,42 @@
+// webcomponents.js code comes from
+// https://github.com/webcomponents/polyfills/tree/master/packages/webcomponentsjs
+//
+// The original code source is available in a "BSD style license".
+//
+// This is the `webcomponents-ce.js` bundle
+pub const source = @embedFile("webcomponents.js");
+
+// The main webcomponents.js is lazilly loaded when window.customElements is
+// called. But, if you look at the test below, you'll notice that we declare
+// our custom element (LightPanda) before we call `customElements.define`. We
+// _have_ to declare it before we can register it.
+// That causes an issue, because the LightPanda class extends HTMLElement, which
+// hasn't been monkeypatched by the polyfill yet. If you were to try it as-is
+// you'd get an "Illegal Constructor", because that's what the Zig HTMLElement
+// constructor does (and that's correct).
+// However, once HTMLElement is monkeypatched, it'll work. One simple solution
+// is to run the webcomponents.js polyfill proactively on each page, ensuring
+// that HTMLElement is monkeypatched before any other JavaScript is run. But
+// that adds _a lot_ of overhead.
+// So instead of always running the [large and intrusive] webcomponents.js
+// polyfill, we'll always run this little snippet. It wraps the HTMLElement
+// constructor. When the Lightpanda class is created, it'll extend our little
+// wrapper. But, unlike the Zig default constructor which throws, our code
+// calls the "real" constructor. That might seem like the same thing, but by the
+// time our wrapper is called, the webcomponents.js polyfill will have been
+// loaded and the "real" constructor will be the monkeypatched version.
+// TL;DR creates a layer of indirection for the constructor, so that, when it's
+// actually instantiated, the webcomponents.js polyfill will have been loaded.
+pub const pre =
+    \\ (() => {
+    \\   const HE = window.HTMLElement;
+    \\   const b = function() { return HE.prototype.constructor.call(this); }
+    \\   b.prototype = HE.prototype;
+    \\   window.HTMLElement = b;
+    \\ })();
+;
+
+const testing = @import("../../testing.zig");
+test "Browser: Polyfill.WebComponents" {
+    try testing.htmlRunner("polyfill/webcomponents.html");
+}

src/browser/session.zig

@@ -56,6 +56,12 @@ pub const Session = struct {
 
     page: ?Page = null,
 
+    // If the current page want to navigate to a new page
+    //  (form submit, link click, top.location = xxx)
+    // the details are stored here so that, on the next call to session.wait
+    // we can destroy the current page and start a new one.
+    queued_navigation: ?QueuedNavigation,
+
     pub fn init(self: *Session, browser: *Browser) !void {
         var executor = try browser.env.newExecutionWorld();
         errdefer executor.deinit();
@@ -64,6 +70,7 @@ pub const Session = struct {
         self.* = .{
             .browser = browser,
             .executor = executor,
+            .queued_navigation = null,
             .arena = browser.session_arena.allocator(),
             .storage_shed = storage.Shed.init(allocator),
             .cookie_jar = storage.CookieJar.init(allocator),
@@ -111,23 +118,13 @@ pub const Session = struct {
 
         std.debug.assert(self.page != null);
 
-        // Cleanup is a bit sensitive. We could still have inflight I/O. For
-        // example, we could have an XHR request which is still in the connect
-        // phase. It's important that we clean these up, as they're holding onto
-        // limited resources (like our fixed-sized http state pool).
-        //
-        // First thing we do, is removeJsContext() which will execute the destructor
-        // of any type that registered a destructor (e.g. XMLHttpRequest).
-        // This will shutdown any pending sockets, which begins our cleaning
-        // processed
+        // RemoveJsContext() will execute the destructor of any type that
+        // registered a destructor (e.g. XMLHttpRequest).
+        // Should be called before we deinit the page, because these objects
+        // could be referencing it.
         self.executor.removeJsContext();
 
-        // Second thing we do is reset the loop. This increments the loop ctx_id
-        // so that any "stale" timeouts we process will get ignored. We need to
-        // do this BEFORE running the loop because, at this point, things like
-        // window.setTimeout and running microtasks should be ignored
-        self.browser.app.loop.reset();
-
+        self.page.?.deinit();
         self.page = null;
 
         // clear netsurf memory arena.
@@ -139,4 +136,47 @@ pub const Session = struct {
     pub fn currentPage(self: *Session) ?*Page {
         return &(self.page orelse return null);
     }
+
+    pub const WaitResult = enum {
+        done,
+        no_page,
+        extra_socket,
+    };
+
+    pub fn wait(self: *Session, wait_ms: i32) WaitResult {
+        if (self.queued_navigation) |qn| {
+            // This was already aborted on the page, but it would be pretty
+            // bad if old requests went to the new page, so let's make double sure
+            self.browser.http_client.abort();
+
+            // Page.navigateFromWebAPI terminatedExecution. If we don't resume
+            // it before doing a shutdown we'll get an error.
+            self.executor.resumeExecution();
+            self.removePage();
+            self.queued_navigation = null;
+
+            const page = self.createPage() catch |err| {
+                log.err(.browser, "queued navigation page error", .{
+                    .err = err,
+                    .url = qn.url,
+                });
+                return .done;
+            };
+
+            page.navigate(qn.url, qn.opts) catch |err| {
+                log.err(.browser, "queued navigation error", .{ .err = err, .url = qn.url });
+                return .done;
+            };
+        }
+
+        if (self.page) |*page| {
+            return page.wait(wait_ms);
+        }
+        return .no_page;
+    }
+};
+
+const QueuedNavigation = struct {
+    url: []const u8,
+    opts: NavigateOpts,
 };

src/browser/storage/cookie.zig

@@ -4,15 +4,15 @@ const Allocator = std.mem.Allocator;
 const ArenaAllocator = std.heap.ArenaAllocator;
 
 const log = @import("../../log.zig");
-const http = @import("../../http/client.zig");
 const DateTime = @import("../../datetime.zig").DateTime;
 const public_suffix_list = @import("../../data/public_suffix_list.zig").lookup;
 
 pub const LookupOpts = struct {
     request_time: ?i64 = null,
     origin_uri: ?*const Uri = null,
-    navigation: bool = true,
     is_http: bool,
+    is_navigation: bool = true,
+    prefix: ?[]const u8 = null,
 };
 
 pub const Jar = struct {
@@ -92,10 +92,15 @@ pub const Jar = struct {
 
         var first = true;
         for (self.cookies.items) |*cookie| {
-            if (!cookie.appliesTo(&target, same_site, opts.navigation, opts.is_http)) continue;
+            if (!cookie.appliesTo(&target, same_site, opts.is_navigation, opts.is_http)) {
+                continue;
+            }
 
             // we have a match!
             if (first) {
+                if (opts.prefix) |prefix| {
+                    try writer.writeAll(prefix);
+                }
                 first = false;
             } else {
                 try writer.writeAll("; ");
@@ -104,16 +109,14 @@ pub const Jar = struct {
         }
     }
 
-    pub fn populateFromResponse(self: *Jar, uri: *const Uri, header: *const http.ResponseHeader) !void {
+    pub fn populateFromResponse(self: *Jar, uri: *const Uri, set_cookie: []const u8) !void {
+        const c = Cookie.parse(self.allocator, uri, set_cookie) catch |err| {
+            log.warn(.web_api, "cookie parse failed", .{ .raw = set_cookie, .err = err });
+            return;
+        };
+
         const now = std.time.timestamp();
-        var it = header.iterate("set-cookie");
-        while (it.next()) |set_cookie| {
-            const c = Cookie.parse(self.allocator, uri, set_cookie) catch |err| {
-                log.warn(.web_api, "cookie parse failed", .{ .raw = set_cookie, .err = err });
-                continue;
-            };
-            try self.add(c, now);
-        }
+        try self.add(c, now);
     }
 
     fn writeCookie(cookie: *const Cookie, writer: anytype) !void {
@@ -296,7 +299,12 @@ pub const Cookie = struct {
                 }
                 if (exp_dt) |dt| {
                     normalized_expires = @floatFromInt(dt.unix(.seconds));
-                } else std.debug.print("Invalid cookie expires value: {s}\n", .{expires_});
+                } else {
+                    // Algolia, for example, will call document.setCookie with
+                    // an expired value which is literally 'Invalid Date'
+                    // (it's trying to do something like: `new Date() + undefined`).
+                    log.debug(.web_api, "cookie expires date", .{ .date = expires_ });
+                }
             }
         }
 
@@ -350,12 +358,10 @@ pub const Cookie = struct {
             if (domain.len > 0) {
                 const no_leading_dot = if (domain[0] == '.') domain[1..] else domain;
 
-                var list = std.ArrayList(u8).init(arena);
-                try list.ensureTotalCapacity(no_leading_dot.len + 1); // Expect no precents needed
-                list.appendAssumeCapacity('.');
-                try std.Uri.Component.percentEncode(list.writer(), no_leading_dot, isHostChar);
-                var owned_domain: []u8 = list.items; // @memory retains memory used before growing
-                _ = toLower(owned_domain);
+                var aw = try std.Io.Writer.Allocating.initCapacity(arena, no_leading_dot.len + 1);
+                try aw.writer.writeByte('.');
+                try std.Uri.Component.percentEncode(&aw.writer, no_leading_dot, isHostChar);
+                const owned_domain = toLower(aw.written());
 
                 if (std.mem.indexOfScalarPos(u8, owned_domain, 1, '.') == null and std.mem.eql(u8, "localhost", owned_domain[1..]) == false) {
                     // can't set a cookie for a TLD
@@ -377,10 +383,9 @@ pub const Cookie = struct {
     pub fn percentEncode(arena: Allocator, component: std.Uri.Component, comptime isValidChar: fn (u8) bool) ![]u8 {
         switch (component) {
             .raw => |str| {
-                var list = std.ArrayList(u8).init(arena);
-                try list.ensureTotalCapacity(str.len); // Expect no precents needed
-                try std.Uri.Component.percentEncode(list.writer(), str, isValidChar);
-                return list.items; // @memory retains memory used before growing
+                var aw = try std.Io.Writer.Allocating.initCapacity(arena, str.len);
+                try std.Uri.Component.percentEncode(&aw.writer, str, isValidChar);
+                return aw.written(); // @memory retains memory used before growing
             },
             .percent_encoded => |str| {
                 return try arena.dupe(u8, str);
@@ -424,7 +429,7 @@ pub const Cookie = struct {
         return .{ name, value, rest };
     }
 
-    pub fn appliesTo(self: *const Cookie, url: *const PreparedUri, same_site: bool, navigation: bool, is_http: bool) bool {
+    pub fn appliesTo(self: *const Cookie, url: *const PreparedUri, same_site: bool, is_navigation: bool, is_http: bool) bool {
         if (self.http_only and is_http == false) {
             // http only cookies can be accessed from Javascript
             return false;
@@ -443,7 +448,7 @@ pub const Cookie = struct {
             // and cookie.same_site == .lax
             switch (self.same_site) {
                 .strict => return false,
-                .lax => if (navigation == false) return false,
+                .lax => if (is_navigation == false) return false,
                 .none => {},
             }
         }
@@ -583,7 +588,7 @@ test "Jar: add" {
 test "Jar: forRequest" {
     const expectCookies = struct {
         fn expect(expected: []const u8, jar: *Jar, target_uri: Uri, opts: LookupOpts) !void {
-            var arr: std.ArrayListUnmanaged(u8) = .{};
+            var arr: std.ArrayListUnmanaged(u8) = .empty;
             defer arr.deinit(testing.allocator);
             try jar.forRequest(&target_uri, arr.writer(testing.allocator), opts);
             try testing.expectEqual(expected, arr.items);
@@ -614,7 +619,7 @@ test "Jar: forRequest" {
 
     // nothing fancy here
     try expectCookies("global1=1; global2=2", &jar, test_uri, .{ .is_http = true });
-    try expectCookies("global1=1; global2=2", &jar, test_uri, .{ .origin_uri = &test_uri, .navigation = false, .is_http = true });
+    try expectCookies("global1=1; global2=2", &jar, test_uri, .{ .origin_uri = &test_uri, .is_navigation = false, .is_http = true });
 
     // We have a cookie where Domain=lightpanda.io
     // This should _not_ match xyxlightpanda.io
@@ -680,22 +685,22 @@ test "Jar: forRequest" {
     // non-navigational cross domain, insecure
     try expectCookies("", &jar, try std.Uri.parse("http://lightpanda.io/x/"), .{
         .origin_uri = &(try std.Uri.parse("https://example.com/")),
-        .navigation = false,
         .is_http = true,
+        .is_navigation = false,
     });
 
     // non-navigational cross domain, secure
     try expectCookies("sitenone=6", &jar, try std.Uri.parse("https://lightpanda.io/x/"), .{
         .origin_uri = &(try std.Uri.parse("https://example.com/")),
-        .navigation = false,
         .is_http = true,
+        .is_navigation = false,
     });
 
     // non-navigational same origin
     try expectCookies("global1=1; global2=2; sitelax=7; sitestrict=8", &jar, try std.Uri.parse("http://lightpanda.io/x/"), .{
         .origin_uri = &(try std.Uri.parse("https://lightpanda.io/")),
-        .navigation = false,
         .is_http = true,
+        .is_navigation = false,
     });
 
     // exact domain match + suffix

src/browser/storage/storage.zig

@@ -130,7 +130,7 @@ pub const Bottle = struct {
         return @intCast(self.map.count());
     }
 
-    pub fn _key(self: *Bottle, idx: u32) ?[]const u8 {
+    pub fn _key(self: *const Bottle, idx: u32) ?[]const u8 {
         if (idx >= self.map.count()) return null;
 
         var it = self.map.valueIterator();
@@ -142,7 +142,7 @@ pub const Bottle = struct {
         unreachable;
     }
 
-    pub fn _getItem(self: *Bottle, k: []const u8) ?[]const u8 {
+    pub fn _getItem(self: *const Bottle, k: []const u8) ?[]const u8 {
         return self.map.get(k);
     }
 
@@ -202,35 +202,25 @@ pub const Bottle = struct {
         //
         // So for now, we won't impement the feature.
     }
+
+    pub fn named_get(self: *const Bottle, name: []const u8, _: *bool) ?[]const u8 {
+        return self._getItem(name);
+    }
+
+    pub fn named_set(self: *Bottle, name: []const u8, value: []const u8, _: *bool) !void {
+        try self._setItem(name, value);
+    }
 };
 
 // Tests
 // -----
 
 const testing = @import("../../testing.zig");
-test "Browser.Storage.LocalStorage" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "localStorage.length", "0" },
-
-        .{ "localStorage.setItem('foo', 'bar')", "undefined" },
-        .{ "localStorage.length", "1" },
-        .{ "localStorage.getItem('foo')", "bar" },
-        .{ "localStorage.removeItem('foo')", "undefined" },
-        .{ "localStorage.length", "0" },
-
-        // .{ "localStorage['foo'] = 'bar'", "undefined" },
-        // .{ "localStorage['foo']", "bar" },
-        // .{ "localStorage.length", "1" },
-
-        .{ "localStorage.clear()", "undefined" },
-        .{ "localStorage.length", "0" },
-    }, .{});
+test "Browser: Storage.LocalStorage" {
+    try testing.htmlRunner("storage/local_storage.html");
 }
 
-test "storage bottle" {
+test "Browser: Storage.Bottle" {
     var bottle = Bottle.init(std.testing.allocator);
     defer bottle.deinit();
 

src/browser/url/url.zig

@@ -54,6 +54,11 @@ pub const URL = struct {
     uri: std.Uri,
     search_params: URLSearchParams,
 
+    pub const empty = URL{
+        .uri = .{ .scheme = "" },
+        .search_params = .{},
+    };
+
     const URLArg = union(enum) {
         url: *URL,
         element: *parser.ElementHTML,
@@ -84,7 +89,17 @@ pub const URL = struct {
             raw = if (url == .url) url_str else try arena.dupe(u8, url_str);
         }
 
-        const uri = std.Uri.parse(raw.?) catch return error.TypeError;
+        const uri = std.Uri.parse(raw.?) catch blk: {
+            if (!std.mem.endsWith(u8, raw.?, "://")) {
+                return error.TypeError;
+            }
+            // schema only is valid!
+            break :blk std.Uri{
+                .scheme = raw.?[0 .. raw.?.len - 3],
+                .host = .{ .percent_encoded = "" },
+            };
+        };
+
         return init(arena, uri);
     }
 
@@ -99,16 +114,16 @@ pub const URL = struct {
     }
 
     pub fn get_origin(self: *URL, page: *Page) ![]const u8 {
-        var buf = std.ArrayList(u8).init(page.arena);
-        try self.uri.writeToStream(.{
+        var aw = std.Io.Writer.Allocating.init(page.arena);
+        try self.uri.writeToStream(&aw.writer, .{
             .scheme = true,
             .authentication = false,
             .authority = true,
             .path = false,
             .query = false,
             .fragment = false,
-        }, buf.writer());
-        return buf.items;
+        });
+        return aw.written();
     }
 
     // get_href returns the URL by writing all its components.
@@ -122,28 +137,28 @@ pub const URL = struct {
 
     // format the url with all its components.
     pub fn toString(self: *const URL, arena: Allocator) ![]const u8 {
-        var buf: std.ArrayListUnmanaged(u8) = .empty;
-        try self.uri.writeToStream(.{
+        var aw = std.Io.Writer.Allocating.init(arena);
+        try self.uri.writeToStream(&aw.writer, .{
             .scheme = true,
             .authentication = true,
             .authority = true,
             .path = uriComponentNullStr(self.uri.path).len > 0,
-        }, buf.writer(arena));
+        });
 
         if (self.search_params.get_size() > 0) {
-            try buf.append(arena, '?');
-            try self.search_params.write(buf.writer(arena));
+            try aw.writer.writeByte('?');
+            try self.search_params.write(&aw.writer);
         }
 
         {
             const fragment = uriComponentNullStr(self.uri.fragment);
             if (fragment.len > 0) {
-                try buf.append(arena, '#');
-                try buf.appendSlice(arena, fragment);
+                try aw.writer.writeByte('#');
+                try aw.writer.writeAll(fragment);
             }
         }
 
-        return buf.items;
+        return aw.written();
     }
 
     pub fn get_protocol(self: *URL, page: *Page) ![]const u8 {
@@ -159,17 +174,16 @@ pub const URL = struct {
     }
 
     pub fn get_host(self: *URL, page: *Page) ![]const u8 {
-        var buf = std.ArrayList(u8).init(page.arena);
-
-        try self.uri.writeToStream(.{
+        var aw = std.Io.Writer.Allocating.init(page.arena);
+        try self.uri.writeToStream(&aw.writer, .{
             .scheme = false,
             .authentication = false,
             .authority = true,
             .path = false,
             .query = false,
             .fragment = false,
-        }, buf.writer());
-        return buf.items;
+        });
+        return aw.written();
     }
 
     pub fn get_hostname(self: *URL) []const u8 {
@@ -180,9 +194,9 @@ pub const URL = struct {
         const arena = page.arena;
         if (self.uri.port == null) return try arena.dupe(u8, "");
 
-        var buf = std.ArrayList(u8).init(arena);
-        try std.fmt.formatInt(self.uri.port.?, 10, .lower, .{}, buf.writer());
-        return buf.items;
+        var aw = std.Io.Writer.Allocating.init(arena);
+        try aw.writer.printInt(self.uri.port.?, 10, .lower, .{});
+        return aw.written();
     }
 
     pub fn get_pathname(self: *URL) []const u8 {
@@ -487,155 +501,10 @@ const ValueIterable = iterator.Iterable(kv.ValueIterator, "URLSearchParamsValueI
 const EntryIterable = iterator.Iterable(kv.EntryIterator, "URLSearchParamsEntryIterator");
 
 const testing = @import("../../testing.zig");
-test "Browser.URL" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-
-    try runner.testCases(&.{
-        .{ "var url = new URL('https://foo.bar/path?query#fragment')", "undefined" },
-        .{ "url.origin", "https://foo.bar" },
-        .{ "url.href", "https://foo.bar/path?query#fragment" },
-        .{ "url.protocol", "https:" },
-        .{ "url.username", "" },
-        .{ "url.password", "" },
-        .{ "url.host", "foo.bar" },
-        .{ "url.hostname", "foo.bar" },
-        .{ "url.port", "" },
-        .{ "url.pathname", "/path" },
-        .{ "url.search", "?query" },
-        .{ "url.hash", "#fragment" },
-        .{ "url.searchParams.get('query')", "" },
-
-        .{ "url.search = 'hello=world'", null },
-        .{ "url.searchParams.size", "1" },
-        .{ "url.searchParams.get('hello')", "world" },
-
-        .{ "url.search = '?over=9000'", null },
-        .{ "url.searchParams.size", "1" },
-        .{ "url.searchParams.get('over')", "9000" },
-
-        .{ "url.search = ''", null },
-        .{ "url.searchParams.size", "0" },
-
-        .{ " const url2 = new URL(url);", null },
-        .{ "url2.href", "https://foo.bar/path#fragment" },
-
-        .{ " try { new URL(document.createElement('a')); } catch (e) { e }", "TypeError: invalid argument" },
-
-        .{ " let a = document.createElement('a');", null },
-        .{ " a.href = 'https://www.lightpanda.io/over?9000=!!';", null },
-        .{ " const url3 = new URL(a);", null },
-        .{ "url3.href", "https://www.lightpanda.io/over?9000=%21%21" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "var url = new URL('https://foo.bar/path?a=~&b=%7E#fragment')", "undefined" },
-        .{ "url.searchParams.get('a')", "~" },
-        .{ "url.searchParams.get('b')", "~" },
-        .{ "url.searchParams.append('c', 'foo')", "undefined" },
-        .{ "url.searchParams.get('c')", "foo" },
-        .{ "url.searchParams.getAll('c').length", "1" },
-        .{ "url.searchParams.getAll('c')[0]", "foo" },
-        .{ "url.searchParams.size", "3" },
-
-        // search is dynamic
-        .{ "url.search", "?a=~&b=~&c=foo" },
-        // href is dynamic
-        .{ "url.href", "https://foo.bar/path?a=~&b=~&c=foo#fragment" },
-
-        .{ "url.searchParams.delete('c', 'foo')", "undefined" },
-        .{ "url.searchParams.get('c')", "null" },
-        .{ "url.searchParams.delete('a')", "undefined" },
-        .{ "url.searchParams.get('a')", "null" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "var url = new URL('over?9000', 'https://lightpanda.io')", null },
-        .{ "url.href", "https://lightpanda.io/over?9000" },
-    }, .{});
+test "Browser: URL" {
+    try testing.htmlRunner("url/url.html");
 }
 
-test "Browser.URLSearchParams" {
-    var runner = try testing.jsRunner(testing.tracking_allocator, .{});
-    defer runner.deinit();
-    try runner.testCases(&.{
-        .{ "let usp = new URLSearchParams()", null },
-        .{ "usp.get('a')", "null" },
-        .{ "usp.has('a')", "false" },
-        .{ "usp.getAll('a')", "" },
-        .{ "usp.delete('a')", "undefined" },
-
-        .{ "usp.set('a', 1)", "undefined" },
-        .{ "usp.has('a')", "true" },
-        .{ "usp.get('a')", "1" },
-        .{ "usp.getAll('a')", "1" },
-
-        .{ "usp.append('a', 2)", "undefined" },
-        .{ "usp.has('a')", "true" },
-        .{ "usp.get('a')", "1" },
-        .{ "usp.getAll('a')", "1,2" },
-
-        .{ "usp.append('b', '3')", "undefined" },
-        .{ "usp.has('a')", "true" },
-        .{ "usp.get('a')", "1" },
-        .{ "usp.getAll('a')", "1,2" },
-        .{ "usp.has('b')", "true" },
-        .{ "usp.get('b')", "3" },
-        .{ "usp.getAll('b')", "3" },
-
-        .{ "let acc = [];", null },
-        .{ "for (const key of usp.keys()) { acc.push(key) }; acc;", "a,a,b" },
-
-        .{ "acc = [];", null },
-        .{ "for (const value of usp.values()) { acc.push(value) }; acc;", "1,2,3" },
-
-        .{ "acc = [];", null },
-        .{ "for (const entry of usp.entries()) { acc.push(entry) }; acc;", "a,1,a,2,b,3" },
-
-        .{ "acc = [];", null },
-        .{ "for (const entry of usp) { acc.push(entry) }; acc;", "a,1,a,2,b,3" },
-
-        .{ "usp.delete('a')", "undefined" },
-        .{ "usp.has('a')", "false" },
-        .{ "usp.has('b')", "true" },
-
-        .{ "acc = [];", null },
-        .{ "for (const key of usp.keys()) { acc.push(key) }; acc;", "b" },
-
-        .{ "acc = [];", null },
-        .{ "for (const value of usp.values()) { acc.push(value) }; acc;", "3" },
-
-        .{ "acc = [];", null },
-        .{ "for (const entry of usp.entries()) { acc.push(entry) }; acc;", "b,3" },
-
-        .{ "acc = [];", null },
-        .{ "for (const entry of usp) { acc.push(entry) }; acc;", "b,3" },
-    }, .{});
-
-    try runner.testCases(&.{
-        .{ "usp = new URLSearchParams('?hello')", null },
-        .{ "usp.get('hello')", "" },
-
-        .{ "usp = new URLSearchParams('?abc=')", null },
-        .{ "usp.get('abc')", "" },
-
-        .{ "usp = new URLSearchParams('?abc=123&')", null },
-        .{ "usp.get('abc')", "123" },
-        .{ "usp.size", "1" },
-
-        .{ "var fd = new FormData()", null },
-        .{ "fd.append('a', '1')", null },
-        .{ "fd.append('a', '2')", null },
-        .{ "fd.append('b', '3')", null },
-        .{ "ups = new URLSearchParams(fd)", null },
-        .{ "ups.size", "3" },
-        .{ "ups.getAll('a')", "1,2" },
-        .{ "ups.getAll('b')", "3" },
-        .{ "fd.delete('a')", null }, // the two aren't linked, it created a copy
-        .{ "ups.size", "3" },
-        .{ "ups = new URLSearchParams({over: 9000, spice: 'flow'})", null },
-        .{ "ups.size", "2" },
-        .{ "ups.getAll('over')", "9000" },
-        .{ "ups.getAll('spice')", "flow" },
-    }, .{});
+test "Browser: URLSearchParams" {
+    try testing.htmlRunner("url/url_search_params.html");
 }