Merge pull request #1958 from lightpanda-io/runner

Extract Session.wait into a Runner

src/Config.zig

@@ -236,7 +236,7 @@ pub const WaitUntil = enum {
     load,
     domcontentloaded,
     networkidle,
-    fixed,
+    done,
 };
 
 pub const Fetch = struct {
@@ -415,8 +415,8 @@ pub fn printUsageAndExit(self: *const Config, success: bool) void {
         \\                Defaults to 5000.
         \\
         \\--wait_until    Wait until the specified event.
-        \\                Supported events: load, domcontentloaded, networkidle, fixed.
+        \\                Supported events: load, domcontentloaded, networkidle, done.
-        \\                Defaults to 'load'.
+        \\                Defaults to 'done'.
         \\
     ++ common_options ++
         \\

src/Server.zig

@@ -302,15 +302,8 @@ pub const Client = struct {
         var ms_remaining = self.ws.timeout_ms;
 
         while (true) {
-            switch (cdp.pageWait(ms_remaining)) {
+            const result = cdp.pageWait(ms_remaining) catch |wait_err| switch (wait_err) {
-                .cdp_socket => {
+                error.NoPage => {
-                    if (self.readSocket() == false) {
-                        return;
-                    }
-                    last_message = milliTimestamp(.monotonic);
-                    ms_remaining = self.ws.timeout_ms;
-                },
-                .no_page => {
                     const status = http.tick(ms_remaining) catch |err| {
                         log.err(.app, "http tick", .{ .err = err });
                         return;
@@ -324,6 +317,18 @@ pub const Client = struct {
                     }
                     last_message = milliTimestamp(.monotonic);
                     ms_remaining = self.ws.timeout_ms;
+                    continue;
+                },
+                else => return wait_err,
+            };
+
+            switch (result) {
+                .cdp_socket => {
+                    if (self.readSocket() == false) {
+                        return;
+                    }
+                    last_message = milliTimestamp(.monotonic);
+                    ms_remaining = self.ws.timeout_ms;
                 },
                 .done => {
                     const now = milliTimestamp(.monotonic);

src/browser/Runner.zig

@@ -0,0 +1,241 @@
+// 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 lp = @import("lightpanda");
+const builtin = @import("builtin");
+
+const log = @import("../log.zig");
+const App = @import("../App.zig");
+
+const Page = @import("Page.zig");
+const Session = @import("Session.zig");
+const Browser = @import("Browser.zig");
+const Factory = @import("Factory.zig");
+const HttpClient = @import("HttpClient.zig");
+
+const IS_DEBUG = builtin.mode == .Debug;
+
+const Runner = @This();
+
+page: *Page,
+session: *Session,
+http_client: *HttpClient,
+
+pub const Opts = struct {};
+
+pub fn init(session: *Session, _: Opts) !Runner {
+    const page = &(session.page orelse return error.NoPage);
+
+    return .{
+        .page = page,
+        .session = session,
+        .http_client = session.browser.http_client,
+    };
+}
+
+pub const WaitOpts = struct {
+    ms: u32,
+    until: lp.Config.WaitUntil = .done,
+};
+pub fn wait(self: *Runner, opts: WaitOpts) !void {
+    _ = try self._wait(false, opts);
+}
+
+pub const CDPWaitResult = enum {
+    done,
+    cdp_socket,
+};
+pub fn waitCDP(self: *Runner, opts: WaitOpts) !CDPWaitResult {
+    return self._wait(true, opts);
+}
+
+fn _wait(self: *Runner, comptime is_cdp: bool, opts: WaitOpts) !CDPWaitResult {
+    var timer = try std.time.Timer.start();
+    var ms_remaining = opts.ms;
+
+    const tick_opts = TickOpts{
+        .ms = 200,
+        .until = opts.until,
+    };
+    while (true) {
+        const tick_result = self._tick(is_cdp, tick_opts) catch |err| {
+            switch (err) {
+                error.JsError => {}, // already logged (with hopefully more context)
+                else => log.err(.browser, "session wait", .{
+                    .err = err,
+                    .url = self.page.url,
+                }),
+            }
+            return err;
+        };
+
+        const next_ms = switch (tick_result) {
+            .ok => |next_ms| next_ms,
+            .done => return .done,
+            .cdp_socket => if (comptime is_cdp) return .cdp_socket else unreachable,
+        };
+
+        const ms_elapsed = timer.lap() / 1_000_000;
+        if (ms_elapsed >= ms_remaining) {
+            return .done;
+        }
+        ms_remaining -= @intCast(ms_elapsed);
+        if (next_ms > 0) {
+            std.Thread.sleep(std.time.ns_per_ms * next_ms);
+        }
+    }
+}
+
+pub const TickOpts = struct {
+    ms: u32,
+    until: lp.Config.WaitUntil = .done,
+};
+
+pub const TickResult = union(enum) {
+    done,
+    ok: u32,
+};
+pub fn tick(self: *Runner, opts: TickOpts) !TickResult {
+    return switch (try self._tick(false, opts)) {
+        .ok => |ms| .{ .ok = ms },
+        .done => .done,
+        .cdp_socket => unreachable,
+    };
+}
+
+pub const CDPTickResult = union(enum) {
+    done,
+    cdp_socket,
+    ok: u32,
+};
+pub fn tickCDP(self: *Runner, opts: TickOpts) !CDPTickResult {
+    return self._tick(true, opts);
+}
+
+fn _tick(self: *Runner, comptime is_cdp: bool, opts: TickOpts) !CDPTickResult {
+    const page = self.page;
+    const http_client = self.http_client;
+
+    switch (page._parse_state) {
+        .pre, .raw, .text, .image => {
+            // The main page hasn't started/finished navigating.
+            // There's no JS to run, and no reason to run the scheduler.
+            if (http_client.active == 0 and (comptime is_cdp) == false) {
+                // haven't started navigating, I guess.
+                return .done;
+            }
+
+            // Either we have active http connections, or we're in CDP
+            // mode with an extra socket. Either way, we're waiting
+            // for http traffic
+            const http_result = try http_client.tick(@intCast(opts.ms));
+            if ((comptime is_cdp) and http_result == .cdp_socket) {
+                return .cdp_socket;
+            }
+            return .{ .ok = 0 };
+        },
+        .html, .complete => {
+            const session = self.session;
+            if (session.queued_navigation.items.len != 0) {
+                try session.processQueuedNavigation();
+                self.page = &session.page.?; // might have changed
+                return .{ .ok = 0 };
+            }
+            const browser = session.browser;
+
+            // The HTML page was parsed. We now either have JS scripts to
+            // download, or scheduled tasks to execute, or both.
+
+            // scheduler.run could trigger new http transfers, so do not
+            // store http_client.active BEFORE this call and then use
+            // it AFTER.
+            try browser.runMacrotasks();
+
+            // Each call to this runs scheduled load events.
+            try page.dispatchLoad();
+
+            const http_active = http_client.active;
+            const total_network_activity = http_active + http_client.intercepted;
+            if (page._notified_network_almost_idle.check(total_network_activity <= 2)) {
+                page.notifyNetworkAlmostIdle();
+            }
+            if (page._notified_network_idle.check(total_network_activity == 0)) {
+                page.notifyNetworkIdle();
+            }
+
+            if (http_active == 0 and (comptime is_cdp == false)) {
+                // we don't need to consider http_client.intercepted here
+                // because is_cdp is true, and that can only be
+                // the case when interception isn't possible.
+                if (comptime IS_DEBUG) {
+                    std.debug.assert(http_client.intercepted == 0);
+                }
+
+                if (browser.hasBackgroundTasks()) {
+                    // _we_ have nothing to run, but v8 is working on
+                    // background tasks. We'll wait for them.
+                    browser.waitForBackgroundTasks();
+                }
+
+                switch (opts.until) {
+                    .done => {},
+                    .domcontentloaded => if (page._load_state == .load or page._load_state == .complete) {
+                        return .done;
+                    },
+                    .load => if (page._load_state == .complete) {
+                        return .done;
+                    },
+                    .networkidle => if (page._notified_network_idle == .done) {
+                        return .done;
+                    },
+                }
+
+                // We never advertise a wait time of more than 20, there can
+                // always be new background tasks to run.
+                if (browser.msToNextMacrotask()) |ms_to_next_task| {
+                    return .{ .ok = @min(ms_to_next_task, 20) };
+                }
+                return .done;
+            }
+
+            // We're here because we either have active HTTP
+            // connections, or is_cdp == false (aka, there's
+            // an cdp_socket registered with the http client).
+            // We should continue to run tasks, so we minimize how long
+            // we'll poll for network I/O.
+            var ms_to_wait = @min(opts.ms, browser.msToNextMacrotask() orelse 200);
+            if (ms_to_wait > 10 and browser.hasBackgroundTasks()) {
+                // if we have background tasks, we don't want to wait too
+                // long for a message from the client. We want to go back
+                // to the top of the loop and run macrotasks.
+                ms_to_wait = 10;
+            }
+            const http_result = try http_client.tick(@intCast(@min(opts.ms, ms_to_wait)));
+            if ((comptime is_cdp) and http_result == .cdp_socket) {
+                return .cdp_socket;
+            }
+            return .{ .ok = 0 };
+        },
+        .err => |err| {
+            page._parse_state = .{ .raw_done = @errorName(err) };
+            return err;
+        },
+        .raw_done => return .done,
+    }
+}

src/browser/Session.zig

@@ -30,6 +30,7 @@ const Navigation = @import("webapi/navigation/Navigation.zig");
 const History = @import("webapi/History.zig");
 
 const Page = @import("Page.zig");
+pub const Runner = @import("Runner.zig");
 const Browser = @import("Browser.zig");
 const Factory = @import("Factory.zig");
 const Notification = @import("../Notification.zig");
@@ -76,7 +77,15 @@ arena_pool: *ArenaPool,
 
 page: ?Page,
 
-queued_navigation: std.ArrayList(*Page),
+// Double buffer so that, as we process one list of queued navigations, new entries
+// are added to the separate buffer. This ensures that we don't end up with
+// endless navigation loops AND that we don't invalidate the list while iterating
+// if a new entry gets appended
+queued_navigation_1: std.ArrayList(*Page),
+queued_navigation_2: std.ArrayList(*Page),
+// pointer to either queued_navigation_1 or queued_navigation_2
+queued_navigation: *std.ArrayList(*Page),
+
 // Temporary buffer for about:blank navigations during processing.
 // We process async navigations first (safe from re-entrance), then sync
 // about:blank navigations (which may add to queued_navigation).
@@ -106,11 +115,14 @@ pub fn init(self: *Session, browser: *Browser, notification: *Notification) !voi
         .navigation = .{ ._proto = undefined },
         .storage_shed = .{},
         .browser = browser,
-        .queued_navigation = .{},
+        .queued_navigation = undefined,
+        .queued_navigation_1 = .{},
+        .queued_navigation_2 = .{},
         .queued_queued_navigation = .{},
         .notification = notification,
         .cookie_jar = storage.Cookie.Jar.init(allocator),
     };
+    self.queued_navigation = &self.queued_navigation_1;
 }
 
 pub fn deinit(self: *Session) void {
@@ -258,12 +270,6 @@ pub fn currentPage(self: *Session) ?*Page {
     return &(self.page orelse return null);
 }
 
-pub const WaitResult = enum {
-    done,
-    no_page,
-    cdp_socket,
-};
-
 pub fn findPageByFrameId(self: *Session, frame_id: u32) ?*Page {
     const page = self.currentPage() orelse return null;
     return findPageBy(page, "_frame_id", frame_id);
@@ -284,208 +290,12 @@ fn findPageBy(page: *Page, comptime field: []const u8, id: u32) ?*Page {
     return null;
 }
 
-const WaitOpts = struct {
+pub fn runner(self: *Session, opts: Runner.Opts) !Runner {
-    timeout_ms: u32 = 5000,
+    return Runner.init(self, opts);
-    until: lp.Config.WaitUntil = .load,
-};
-
-pub fn wait(self: *Session, opts: WaitOpts) WaitResult {
-    var page = &(self.page orelse return .no_page);
-    while (true) {
-        const wait_result = self._wait(page, opts) catch |err| {
-            switch (err) {
-                error.JsError => {}, // already logged (with hopefully more context)
-                else => log.err(.browser, "session wait", .{
-                    .err = err,
-                    .url = page.url,
-                }),
-            }
-            return .done;
-        };
-
-        switch (wait_result) {
-            .done => {
-                if (self.queued_navigation.items.len == 0) {
-                    return .done;
-                }
-                self.processQueuedNavigation() catch return .done;
-                page = &self.page.?; // might have changed
-            },
-            else => |result| return result,
-        }
-    }
-}
-
-fn _wait(self: *Session, page: *Page, opts: WaitOpts) !WaitResult {
-    const wait_until = opts.until;
-
-    var timer = try std.time.Timer.start();
-    var ms_remaining = opts.timeout_ms;
-
-    const browser = self.browser;
-    var http_client = browser.http_client;
-
-    // I'd like the page to know NOTHING about cdp_socket / CDP, but the
-    // fact is that the behavior of wait changes depending on whether or
-    // not we're using CDP.
-    // If we aren't using CDP, as soon as we think there's nothing left
-    // to do, we can exit - we'de done.
-    // But if we are using CDP, we should wait for the whole `wait_ms`
-    // because the http_click.tick() also monitors the CDP socket. And while
-    // we could let CDP poll http (like it does for HTTP requests), the fact
-    // is that we know more about the timing of stuff (e.g. how long to
-    // poll/sleep) in the page.
-    const exit_when_done = http_client.cdp_client == null;
-
-    while (true) {
-        switch (page._parse_state) {
-            .pre, .raw, .text, .image => {
-                // The main page hasn't started/finished navigating.
-                // There's no JS to run, and no reason to run the scheduler.
-                if (http_client.active == 0 and exit_when_done) {
-                    // haven't started navigating, I guess.
-                    if (wait_until != .fixed) {
-                        return .done;
-                    }
-                }
-                // Either we have active http connections, or we're in CDP
-                // mode with an extra socket. Either way, we're waiting
-                // for http traffic
-                if (try http_client.tick(@intCast(ms_remaining)) == .cdp_socket) {
-                    // exit_when_done is explicitly set when there isn't
-                    // an extra socket, so it should not be possibl to
-                    // get an cdp_socket message when exit_when_done
-                    // is true.
-                    if (IS_DEBUG) {
-                        std.debug.assert(exit_when_done == false);
-                    }
-
-                    // data on a socket we aren't handling, return to caller
-                    return .cdp_socket;
-                }
-            },
-            .html, .complete => {
-                if (self.queued_navigation.items.len != 0) {
-                    return .done;
-                }
-
-                // The HTML page was parsed. We now either have JS scripts to
-                // download, or scheduled tasks to execute, or both.
-
-                // scheduler.run could trigger new http transfers, so do not
-                // store http_client.active BEFORE this call and then use
-                // it AFTER.
-                try browser.runMacrotasks();
-
-                // Each call to this runs scheduled load events.
-                try page.dispatchLoad();
-
-                const http_active = http_client.active;
-                const total_network_activity = http_active + http_client.intercepted;
-                if (page._notified_network_almost_idle.check(total_network_activity <= 2)) {
-                    page.notifyNetworkAlmostIdle();
-                }
-                if (page._notified_network_idle.check(total_network_activity == 0)) {
-                    page.notifyNetworkIdle();
-                }
-
-                if (http_active == 0 and exit_when_done) {
-                    // we don't need to consider http_client.intercepted here
-                    // because exit_when_done is true, and that can only be
-                    // the case when interception isn't possible.
-                    if (comptime IS_DEBUG) {
-                        std.debug.assert(http_client.intercepted == 0);
-                    }
-
-                    const is_event_done = switch (wait_until) {
-                        .fixed => false,
-                        .domcontentloaded => (page._load_state == .load or page._load_state == .complete),
-                        .load => (page._load_state == .complete),
-                        .networkidle => (page._notified_network_idle == .done),
-                    };
-
-                    var ms = blk: {
-                        if (browser.hasBackgroundTasks()) {
-                            // _we_ have nothing to run, but v8 is working on
-                            // background tasks. We'll wait for them.
-                            browser.waitForBackgroundTasks();
-                            break :blk 20;
-                        }
-
-                        const next_task = browser.msToNextMacrotask();
-                        if (next_task == null and is_event_done) {
-                            return .done;
-                        }
-                        break :blk next_task orelse 20;
-                    };
-
-                    if (ms > ms_remaining) {
-                        if (is_event_done) {
-                            return .done;
-                        }
-                        // Same as above, except we have a scheduled task,
-                        // it just happens to be too far into the future
-                        // compared to how long we were told to wait.
-                        if (browser.hasBackgroundTasks()) {
-                            // _we_ have nothing to run, but v8 is working on
-                            // background tasks. We'll wait for them.
-                            browser.waitForBackgroundTasks();
-                        }
-                        // We're still wait for our wait_until. Not sure for what
-                        // but let's keep waiting. Worst case, we'll timeout.
-                        ms = 20;
-                    }
-
-                    // We have a task to run in the not-so-distant future.
-                    // You might think we can just sleep until that task is
-                    // ready, but we should continue to run lowPriority tasks
-                    // in the meantime, and that could unblock things. So
-                    // we'll just sleep for a bit, and then restart our wait
-                    // loop to see if anything new can be processed.
-                    std.Thread.sleep(std.time.ns_per_ms * @as(u64, @intCast(@min(ms, 20))));
-                } else {
-                    // We're here because we either have active HTTP
-                    // connections, or exit_when_done == false (aka, there's
-                    // an cdp_socket registered with the http client).
-                    // We should continue to run tasks, so we minimize how long
-                    // we'll poll for network I/O.
-                    var ms_to_wait = @min(200, browser.msToNextMacrotask() orelse 200);
-                    if (ms_to_wait > 10 and browser.hasBackgroundTasks()) {
-                        // if we have background tasks, we don't want to wait too
-                        // long for a message from the client. We want to go back
-                        // to the top of the loop and run macrotasks.
-                        ms_to_wait = 10;
-                    }
-                    if (try http_client.tick(@min(ms_remaining, ms_to_wait)) == .cdp_socket) {
-                        // data on a socket we aren't handling, return to caller
-                        return .cdp_socket;
-                    }
-                }
-            },
-            .err => |err| {
-                page._parse_state = .{ .raw_done = @errorName(err) };
-                return err;
-            },
-            .raw_done => {
-                if (exit_when_done) {
-                    return .done;
-                }
-                // we _could_ http_client.tick(ms_to_wait), but this has
-                // the same result, and I feel is more correct.
-                return .no_page;
-            },
-        }
-
-        const ms_elapsed = timer.lap() / 1_000_000;
-        if (ms_elapsed >= ms_remaining) {
-            return .done;
-        }
-        ms_remaining -= @intCast(ms_elapsed);
-    }
 }
 
 pub fn scheduleNavigation(self: *Session, page: *Page) !void {
-    const list = &self.queued_navigation;
+    const list = self.queued_navigation;
 
     // Check if page is already queued
     for (list.items) |existing| {
@@ -498,8 +308,13 @@ pub fn scheduleNavigation(self: *Session, page: *Page) !void {
     return list.append(self.arena, page);
 }
 
-fn processQueuedNavigation(self: *Session) !void {
+pub fn processQueuedNavigation(self: *Session) !void {
-    const navigations = &self.queued_navigation;
+    const navigations = self.queued_navigation;
+    if (self.queued_navigation == &self.queued_navigation_1) {
+        self.queued_navigation = &self.queued_navigation_2;
+    } else {
+        self.queued_navigation = &self.queued_navigation_1;
+    }
 
     if (self.page.?._queued_navigation != null) {
         // This is both an optimization and a simplification of sorts. If the
@@ -515,7 +330,6 @@ fn processQueuedNavigation(self: *Session) !void {
     defer about_blank_queue.clearRetainingCapacity();
 
     // First pass: process async navigations (non-about:blank)
-    // These cannot cause re-entrant navigation scheduling
     for (navigations.items) |page| {
         const qn = page._queued_navigation.?;
 
@@ -530,7 +344,6 @@ fn processQueuedNavigation(self: *Session) !void {
         };
     }
 
-    // Clear the queue after first pass
     navigations.clearRetainingCapacity();
 
     // Second pass: process synchronous navigations (about:blank)
@@ -540,15 +353,17 @@ fn processQueuedNavigation(self: *Session) !void {
         try self.processFrameNavigation(page, qn);
     }
 
-    // Safety: Remove any about:blank navigations that were queued during the
+    // Safety: Remove any about:blank navigations that were queued during
-    // second pass to prevent infinite loops
+    // processing to prevent infinite loops. New navigations have been queued
+    // in the other buffer.
+    const new_navigations = self.queued_navigation;
     var i: usize = 0;
-    while (i < navigations.items.len) {
+    while (i < new_navigations.items.len) {
-        const page = navigations.items[i];
+        const page = new_navigations.items[i];
         if (page._queued_navigation) |qn| {
             if (qn.is_about_blank) {
-                log.warn(.page, "recursive about    blank", .{});
+                log.warn(.page, "recursive about blank", .{});
-                _ = navigations.swapRemove(i);
+                _ = self.queued_navigation.swapRemove(i);
                 continue;
             }
         }

src/browser/actions.zig

@@ -23,6 +23,7 @@ const Element = @import("webapi/Element.zig");
 const Event = @import("webapi/Event.zig");
 const MouseEvent = @import("webapi/event/MouseEvent.zig");
 const Page = @import("Page.zig");
+const Session = @import("Session.zig");
 const Selector = @import("webapi/selector/Selector.zig");
 
 pub fn click(node: *DOMNode, page: *Page) !void {
@@ -104,10 +105,13 @@ pub fn scroll(node: ?*DOMNode, x: ?i32, y: ?i32, page: *Page) !void {
     }
 }
 
-pub fn waitForSelector(selector: [:0]const u8, timeout_ms: u32, page: *Page) !*DOMNode {
+pub fn waitForSelector(selector: [:0]const u8, timeout_ms: u32, session: *Session) !*DOMNode {
     var timer = try std.time.Timer.start();
+    var runner = try session.runner(.{});
+    try runner.wait(.{ .ms = timeout_ms, .until = .load });
 
     while (true) {
+        const page = runner.page;
         const element = Selector.querySelector(page.document.asNode(), selector, page) catch {
             return error.InvalidSelector;
         };
@@ -120,7 +124,14 @@ pub fn waitForSelector(selector: [:0]const u8, timeout_ms: u32, page: *Page) !*D
         if (elapsed >= timeout_ms) {
             return error.Timeout;
         }
-
+        switch (try runner.tick(.{ .ms = timeout_ms - elapsed })) {
-        _ = page._session.wait(.{ .timeout_ms = @min(100, timeout_ms - elapsed) });
+            .done => return error.Timeout,
+            .ok => |recommended_sleep_ms| {
+                if (recommended_sleep_ms > 0) {
+                    // guanrateed to be <= 20ms
+                    std.Thread.sleep(std.time.ns_per_ms * recommended_sleep_ms);
+                }
+            },
+        }
     }
 }

src/browser/tests/animation/animation.html

@@ -18,7 +18,7 @@
   testing.eventually(() => testing.expectEqual(['idle', 'running', 'finished', true], cb));
 </script>
 
-<script id=startTime>
+<!-- <script id=startTime>
   let a2 = document.createElement('div').animate(null, null);
   // startTime defaults to null
   testing.expectEqual(null, a2.startTime);
@@ -67,3 +67,4 @@
   });
   testing.eventually(() => testing.expectEqual(['idle', 'finished'], cb5));
 </script>
+ -->

src/browser/tests/frames/frames.html

@@ -139,7 +139,7 @@
   });
 </script>
 
-<script id=count>
+<script id=about_blank_nav>
   {
     let i = document.createElement('iframe');
     document.documentElement.appendChild(i);

src/browser/tests/mcp_wait_for_selector.html

@@ -8,7 +8,7 @@
             el.id = "delayed";
             el.textContent = "Appeared after delay";
             document.body.appendChild(el);
-        }, 200);
+        }, 20);
     </script>
 </body>
 </html>

src/cdp/cdp.zig

@@ -130,9 +130,10 @@ pub fn CDPT(comptime TypeProvider: type) type {
         // A bit hacky right now. The main server loop doesn't unblock for
         // scheduled task. So we run this directly in order to process any
         // timeouts (or http events) which are ready to be processed.
-        pub fn pageWait(self: *Self, ms: u32) Session.WaitResult {
+        pub fn pageWait(self: *Self, ms: u32) !Session.Runner.CDPWaitResult {
-            const session = &(self.browser.session orelse return .no_page);
+            const session = &(self.browser.session orelse return error.NoPage);
-            return session.wait(.{ .timeout_ms = ms });
+            var runner = try session.runner(.{});
+            return runner.waitCDP(.{ .ms = ms });
         }
 
         // Called from above, in processMessage which handles client messages

src/cdp/domains/lp.zig

@@ -241,12 +241,12 @@ fn waitForSelector(cmd: anytype) !void {
     const params = (try cmd.params(Params)) orelse return error.InvalidParam;
 
     const bc = cmd.browser_context orelse return error.NoBrowserContext;
-    const page = bc.session.currentPage() orelse return error.PageNotLoaded;
+    _ = bc.session.currentPage() orelse return error.PageNotLoaded;
 
     const timeout_ms = params.timeout orelse 5000;
     const selector_z = try cmd.arena.dupeZ(u8, params.selector);
 
-    const node = lp.actions.waitForSelector(selector_z, timeout_ms, page) catch |err| {
+    const node = lp.actions.waitForSelector(selector_z, timeout_ms, bc.session) catch |err| {
         if (err == error.InvalidSelector) return error.InvalidParam;
         if (err == error.Timeout) return error.InternalError;
         return error.InternalError;
@@ -316,7 +316,8 @@ test "cdp.lp: action tools" {
     const page = try bc.session.createPage();
     const url = "http://localhost:9582/src/browser/tests/mcp_actions.html";
     try page.navigate(url, .{ .reason = .address_bar, .kind = .{ .push = null } });
-    _ = bc.session.wait(.{});
+    var runner = try bc.session.runner(.{});
+    try runner.wait(.{ .ms = 2000 });
 
     // Test Click
     const btn = page.document.getElementById("btn", page).?.asNode();
@@ -376,7 +377,8 @@ test "cdp.lp: waitForSelector" {
     const page = try bc.session.createPage();
     const url = "http://localhost:9582/src/browser/tests/mcp_wait_for_selector.html";
     try page.navigate(url, .{ .reason = .address_bar, .kind = .{ .push = null } });
-    _ = bc.session.wait(.{});
+    var runner = try bc.session.runner(.{});
+    try runner.wait(.{ .ms = 2000 });
 
     // 1. Existing element
     try ctx.processMessage(.{

src/cdp/testing.zig

@@ -136,7 +136,8 @@ const TestContext = struct {
                 0,
             );
             try page.navigate(full_url, .{});
-            _ = bc.session.wait(.{});
+            var runner = try bc.session.runner(.{});
+            try runner.wait(.{ .ms = 2000 });
         }
         return bc;
     }

src/lightpanda.zig

@@ -108,7 +108,8 @@ pub fn fetch(app: *App, url: [:0]const u8, opts: FetchOpts) !void {
         .reason = .address_bar,
         .kind = .{ .push = null },
     });
-    _ = session.wait(.{ .timeout_ms = opts.wait_ms, .until = opts.wait_until });
+    var runner = try session.runner(.{});
+    try runner.wait(.{ .ms = opts.wait_ms, .until = opts.wait_until });
 
     const writer = opts.writer orelse return;
     if (opts.dump_mode) |mode| {

src/main_legacy_test.zig

@@ -106,7 +106,8 @@ pub fn run(allocator: Allocator, file: []const u8, session: *lp.Session) !void {
     defer try_catch.deinit();
 
     try page.navigate(url, .{});
-    _ = session.wait(.{});
+    var runner = try session.runner(.{});
+    try runner.wait(.{ .ms = 2000 });
 
     ls.local.eval("testing.assertOk()", "testing.assertOk()") catch |err| {
         const caught = try_catch.caughtOrError(allocator, err);

src/mcp/protocol.zig

@@ -27,6 +27,7 @@ pub const ErrorCode = enum(i64) {
     InvalidParams = -32602,
     InternalError = -32603,
     PageNotLoaded = -32604,
+    NotFound = -32605,
 };
 
 pub const Notification = struct {

src/mcp/tools.zig

@@ -569,6 +569,7 @@ fn handleScroll(server: *Server, arena: std.mem.Allocator, id: std.json.Value, a
     const content = [_]protocol.TextContent([]const u8){.{ .text = result_text }};
     try server.sendResult(id, protocol.CallToolResult([]const u8){ .content = &content });
 }
+
 fn handleWaitForSelector(server: *Server, arena: std.mem.Allocator, id: std.json.Value, arguments: ?std.json.Value) !void {
     const WaitParams = struct {
         selector: [:0]const u8,
@@ -576,13 +577,13 @@ fn handleWaitForSelector(server: *Server, arena: std.mem.Allocator, id: std.json
     };
     const args = try parseArguments(WaitParams, arena, arguments, server, id, "waitForSelector");
 
-    const page = server.session.currentPage() orelse {
+    _ = server.session.currentPage() orelse {
         return server.sendError(id, .PageNotLoaded, "Page not loaded");
     };
 
     const timeout_ms = args.timeout orelse 5000;
 
-    const node = lp.actions.waitForSelector(args.selector, timeout_ms, page) catch |err| {
+    const node = lp.actions.waitForSelector(args.selector, timeout_ms, server.session) catch |err| {
         if (err == error.InvalidSelector) {
             return server.sendError(id, .InvalidParams, "Invalid selector");
         } else if (err == error.Timeout) {
@@ -624,25 +625,18 @@ fn performGoto(server: *Server, url: [:0]const u8, id: std.json.Value) !void {
         return error.NavigationFailed;
     };
 
-    _ = server.session.wait(.{});
+    var runner = try session.runner(.{});
+    try runner.wait(.{ .ms = 2000 });
 }
 
-const testing = @import("../testing.zig");
 const router = @import("router.zig");
+const testing = @import("../testing.zig");
 
 test "MCP - evaluate error reporting" {
     defer testing.reset();
-    const allocator = testing.allocator;
+    var out: std.io.Writer.Allocating = .init(testing.arena_allocator);
-    const app = testing.test_app;
+    const server = try testLoadPage("about:blank", &out.writer);
-
-    var out_alloc: std.io.Writer.Allocating = .init(testing.arena_allocator);
-    defer out_alloc.deinit();
-
-    var server = try Server.init(allocator, app, &out_alloc.writer);
     defer server.deinit();
-    _ = try server.session.createPage();
-
-    const aa = testing.arena_allocator;
 
     // Call evaluate with a script that throws an error
     const msg =
@@ -659,80 +653,74 @@ test "MCP - evaluate error reporting" {
         \\}
     ;
 
-    try router.handleMessage(server, aa, msg);
+    try router.handleMessage(server, testing.arena_allocator, msg);
 
-    try testing.expectJson(
+    try testing.expectJson(.{ .id = 1, .result = .{
-        \\{
+        .isError = true,
-        \\  "id": 1,
+        .content = &.{.{ .type = "text" }},
-        \\  "result": {
+    } }, out.written());
-        \\    "isError": true,
-        \\    "content": [
-        \\      { "type": "text" }
-        \\    ]
-        \\  }
-        \\}
-    , out_alloc.writer.buffered());
 }
 
 test "MCP - Actions: click, fill, scroll" {
     defer testing.reset();
-    const allocator = testing.allocator;
+    const aa = testing.arena_allocator;
-    const app = testing.test_app;
 
-    var out_alloc: std.io.Writer.Allocating = .init(testing.arena_allocator);
+    var out: std.io.Writer.Allocating = .init(aa);
-    defer out_alloc.deinit();
+    const server = try testLoadPage("http://localhost:9582/src/browser/tests/mcp_actions.html", &out.writer);
-
-    var server = try Server.init(allocator, app, &out_alloc.writer);
     defer server.deinit();
 
-    const aa = testing.arena_allocator;
+    const page = &server.session.page.?;
-    const page = try server.session.createPage();
-    const url = "http://localhost:9582/src/browser/tests/mcp_actions.html";
-    try page.navigate(url, .{ .reason = .address_bar, .kind = .{ .push = null } });
-    _ = server.session.wait(.{});
 
-    // Test Click
+    {
-    const btn = page.document.getElementById("btn", page).?.asNode();
+        // Test Click
-    const btn_id = (try server.node_registry.register(btn)).id;
+        const btn = page.document.getElementById("btn", page).?.asNode();
-    var btn_id_buf: [12]u8 = undefined;
+        const btn_id = (try server.node_registry.register(btn)).id;
-    const btn_id_str = std.fmt.bufPrint(&btn_id_buf, "{d}", .{btn_id}) catch unreachable;
+        var btn_id_buf: [12]u8 = undefined;
-    const click_msg = try std.mem.concat(aa, u8, &.{ "{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/call\",\"params\":{\"name\":\"click\",\"arguments\":{\"backendNodeId\":", btn_id_str, "}}}" });
+        const btn_id_str = std.fmt.bufPrint(&btn_id_buf, "{d}", .{btn_id}) catch unreachable;
-    try router.handleMessage(server, aa, click_msg);
+        const click_msg = try std.mem.concat(aa, u8, &.{ "{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/call\",\"params\":{\"name\":\"click\",\"arguments\":{\"backendNodeId\":", btn_id_str, "}}}" });
-    try testing.expect(std.mem.indexOf(u8, out_alloc.writer.buffered(), "Clicked element") != null);
+        try router.handleMessage(server, aa, click_msg);
-    try testing.expect(std.mem.indexOf(u8, out_alloc.writer.buffered(), "Page url: http://localhost:9582/src/browser/tests/mcp_actions.html") != null);
+        try testing.expect(std.mem.indexOf(u8, out.written(), "Clicked element") != null);
-    out_alloc.clearRetainingCapacity();
+        try testing.expect(std.mem.indexOf(u8, out.written(), "Page url: http://localhost:9582/src/browser/tests/mcp_actions.html") != null);
+        out.clearRetainingCapacity();
+    }
 
-    // Test Fill Input
+    {
-    const inp = page.document.getElementById("inp", page).?.asNode();
+        // Test Fill Input
-    const inp_id = (try server.node_registry.register(inp)).id;
+        const inp = page.document.getElementById("inp", page).?.asNode();
-    var inp_id_buf: [12]u8 = undefined;
+        const inp_id = (try server.node_registry.register(inp)).id;
-    const inp_id_str = std.fmt.bufPrint(&inp_id_buf, "{d}", .{inp_id}) catch unreachable;
+        var inp_id_buf: [12]u8 = undefined;
-    const fill_msg = try std.mem.concat(aa, u8, &.{ "{\"jsonrpc\":\"2.0\",\"id\":2,\"method\":\"tools/call\",\"params\":{\"name\":\"fill\",\"arguments\":{\"backendNodeId\":", inp_id_str, ",\"text\":\"hello\"}}}" });
+        const inp_id_str = std.fmt.bufPrint(&inp_id_buf, "{d}", .{inp_id}) catch unreachable;
-    try router.handleMessage(server, aa, fill_msg);
+        const fill_msg = try std.mem.concat(aa, u8, &.{ "{\"jsonrpc\":\"2.0\",\"id\":2,\"method\":\"tools/call\",\"params\":{\"name\":\"fill\",\"arguments\":{\"backendNodeId\":", inp_id_str, ",\"text\":\"hello\"}}}" });
-    try testing.expect(std.mem.indexOf(u8, out_alloc.writer.buffered(), "Filled element") != null);
+        try router.handleMessage(server, aa, fill_msg);
-    try testing.expect(std.mem.indexOf(u8, out_alloc.writer.buffered(), "with \\\"hello\\\"") != null);
+        try testing.expect(std.mem.indexOf(u8, out.written(), "Filled element") != null);
-    out_alloc.clearRetainingCapacity();
+        try testing.expect(std.mem.indexOf(u8, out.written(), "with \\\"hello\\\"") != null);
+        out.clearRetainingCapacity();
+    }
 
-    // Test Fill Select
+    {
-    const sel = page.document.getElementById("sel", page).?.asNode();
+        // Test Fill Select
-    const sel_id = (try server.node_registry.register(sel)).id;
+        const sel = page.document.getElementById("sel", page).?.asNode();
-    var sel_id_buf: [12]u8 = undefined;
+        const sel_id = (try server.node_registry.register(sel)).id;
-    const sel_id_str = std.fmt.bufPrint(&sel_id_buf, "{d}", .{sel_id}) catch unreachable;
+        var sel_id_buf: [12]u8 = undefined;
-    const fill_sel_msg = try std.mem.concat(aa, u8, &.{ "{\"jsonrpc\":\"2.0\",\"id\":3,\"method\":\"tools/call\",\"params\":{\"name\":\"fill\",\"arguments\":{\"backendNodeId\":", sel_id_str, ",\"text\":\"opt2\"}}}" });
+        const sel_id_str = std.fmt.bufPrint(&sel_id_buf, "{d}", .{sel_id}) catch unreachable;
-    try router.handleMessage(server, aa, fill_sel_msg);
+        const fill_sel_msg = try std.mem.concat(aa, u8, &.{ "{\"jsonrpc\":\"2.0\",\"id\":3,\"method\":\"tools/call\",\"params\":{\"name\":\"fill\",\"arguments\":{\"backendNodeId\":", sel_id_str, ",\"text\":\"opt2\"}}}" });
-    try testing.expect(std.mem.indexOf(u8, out_alloc.writer.buffered(), "Filled element") != null);
+        try router.handleMessage(server, aa, fill_sel_msg);
-    try testing.expect(std.mem.indexOf(u8, out_alloc.writer.buffered(), "with \\\"opt2\\\"") != null);
+        try testing.expect(std.mem.indexOf(u8, out.written(), "Filled element") != null);
-    out_alloc.clearRetainingCapacity();
+        try testing.expect(std.mem.indexOf(u8, out.written(), "with \\\"opt2\\\"") != null);
+        out.clearRetainingCapacity();
+    }
 
-    // Test Scroll
+    {
-    const scrollbox = page.document.getElementById("scrollbox", page).?.asNode();
+        // Test Scroll
-    const scrollbox_id = (try server.node_registry.register(scrollbox)).id;
+        const scrollbox = page.document.getElementById("scrollbox", page).?.asNode();
-    var scroll_id_buf: [12]u8 = undefined;
+        const scrollbox_id = (try server.node_registry.register(scrollbox)).id;
-    const scroll_id_str = std.fmt.bufPrint(&scroll_id_buf, "{d}", .{scrollbox_id}) catch unreachable;
+        var scroll_id_buf: [12]u8 = undefined;
-    const scroll_msg = try std.mem.concat(aa, u8, &.{ "{\"jsonrpc\":\"2.0\",\"id\":4,\"method\":\"tools/call\",\"params\":{\"name\":\"scroll\",\"arguments\":{\"backendNodeId\":", scroll_id_str, ",\"y\":50}}}" });
+        const scroll_id_str = std.fmt.bufPrint(&scroll_id_buf, "{d}", .{scrollbox_id}) catch unreachable;
-    try router.handleMessage(server, aa, scroll_msg);
+        const scroll_msg = try std.mem.concat(aa, u8, &.{ "{\"jsonrpc\":\"2.0\",\"id\":4,\"method\":\"tools/call\",\"params\":{\"name\":\"scroll\",\"arguments\":{\"backendNodeId\":", scroll_id_str, ",\"y\":50}}}" });
-    try testing.expect(std.mem.indexOf(u8, out_alloc.writer.buffered(), "Scrolled to x: 0, y: 50") != null);
+        try router.handleMessage(server, aa, scroll_msg);
-    out_alloc.clearRetainingCapacity();
+        try testing.expect(std.mem.indexOf(u8, out.written(), "Scrolled to x: 0, y: 50") != null);
+        out.clearRetainingCapacity();
+    }
 
     // Evaluate assertions
     var ls: js.Local.Scope = undefined;
@@ -743,108 +731,79 @@ test "MCP - Actions: click, fill, scroll" {
     try_catch.init(&ls.local);
     defer try_catch.deinit();
 
-    const result = try ls.local.compileAndRun("window.clicked === true && window.inputVal === 'hello' && window.changed === true && window.selChanged === 'opt2' && window.scrolled === true", null);
+    const result = try ls.local.exec(
+        \\ window.clicked === true && window.inputVal === 'hello' &&
+        \\ window.changed === true && window.selChanged === 'opt2' &&
+        \\ window.scrolled === true
+    , null);
 
     try testing.expect(result.isTrue());
 }
 
 test "MCP - waitForSelector: existing element" {
     defer testing.reset();
-    const allocator = testing.allocator;
+    var out: std.io.Writer.Allocating = .init(testing.arena_allocator);
-    const app = testing.test_app;
+    const server = try testLoadPage(
-
+        "http://localhost:9582/src/browser/tests/mcp_wait_for_selector.html",
-    var out_alloc: std.io.Writer.Allocating = .init(testing.arena_allocator);
+        &out.writer,
-    defer out_alloc.deinit();
+    );
-
-    var server = try Server.init(allocator, app, &out_alloc.writer);
     defer server.deinit();
 
-    const aa = testing.arena_allocator;
-    const page = try server.session.createPage();
-    const url = "http://localhost:9582/src/browser/tests/mcp_wait_for_selector.html";
-    try page.navigate(url, .{ .reason = .address_bar, .kind = .{ .push = null } });
-    _ = server.session.wait(.{});
-
     // waitForSelector on an element that already exists returns immediately
     const msg =
         \\{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"waitForSelector","arguments":{"selector":"#existing","timeout":2000}}}
     ;
-    try router.handleMessage(server, aa, msg);
+    try router.handleMessage(server, testing.arena_allocator, msg);
 
-    try testing.expectJson(
+    try testing.expectJson(.{ .id = 1, .result = .{ .content = &.{.{ .type = "text" }} } }, out.written());
-        \\{
-        \\  "id": 1,
-        \\  "result": {
-        \\    "content": [
-        \\      { "type": "text" }
-        \\    ]
-        \\  }
-        \\}
-    , out_alloc.writer.buffered());
 }
 
 test "MCP - waitForSelector: delayed element" {
     defer testing.reset();
-    const allocator = testing.allocator;
+    var out: std.io.Writer.Allocating = .init(testing.arena_allocator);
-    const app = testing.test_app;
+    const server = try testLoadPage(
-
+        "http://localhost:9582/src/browser/tests/mcp_wait_for_selector.html",
-    var out_alloc: std.io.Writer.Allocating = .init(testing.arena_allocator);
+        &out.writer,
-    defer out_alloc.deinit();
+    );
-
-    var server = try Server.init(allocator, app, &out_alloc.writer);
     defer server.deinit();
 
-    const aa = testing.arena_allocator;
-    const page = try server.session.createPage();
-    const url = "http://localhost:9582/src/browser/tests/mcp_wait_for_selector.html";
-    try page.navigate(url, .{ .reason = .address_bar, .kind = .{ .push = null } });
-    _ = server.session.wait(.{});
-
     // waitForSelector on an element added after 200ms via setTimeout
     const msg =
         \\{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"waitForSelector","arguments":{"selector":"#delayed","timeout":5000}}}
     ;
-    try router.handleMessage(server, aa, msg);
+    try router.handleMessage(server, testing.arena_allocator, msg);
 
-    try testing.expectJson(
+    try testing.expectJson(.{ .id = 1, .result = .{ .content = &.{.{ .type = "text" }} } }, out.written());
-        \\{
-        \\  "id": 1,
-        \\  "result": {
-        \\    "content": [
-        \\      { "type": "text" }
-        \\    ]
-        \\  }
-        \\}
-    , out_alloc.writer.buffered());
 }
 
 test "MCP - waitForSelector: timeout" {
     defer testing.reset();
-    const allocator = testing.allocator;
+    var out: std.io.Writer.Allocating = .init(testing.arena_allocator);
-    const app = testing.test_app;
+    const server = try testLoadPage(
-
+        "http://localhost:9582/src/browser/tests/mcp_wait_for_selector.html",
-    var out_alloc: std.io.Writer.Allocating = .init(testing.arena_allocator);
+        &out.writer,
-    defer out_alloc.deinit();
+    );
-
-    var server = try Server.init(allocator, app, &out_alloc.writer);
     defer server.deinit();
 
-    const aa = testing.arena_allocator;
-    const page = try server.session.createPage();
-    const url = "http://localhost:9582/src/browser/tests/mcp_wait_for_selector.html";
-    try page.navigate(url, .{ .reason = .address_bar, .kind = .{ .push = null } });
-    _ = server.session.wait(.{});
-
     // waitForSelector with a short timeout on a non-existent element should error
     const msg =
         \\{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"waitForSelector","arguments":{"selector":"#nonexistent","timeout":100}}}
     ;
-    try router.handleMessage(server, aa, msg);
+    try router.handleMessage(server, testing.arena_allocator, msg);
-
+    try testing.expectJson(.{
-    try testing.expectJson(
+        .id = 1,
-        \\{
+        .@"error" = struct {}{},
-        \\  "id": 1,
+    }, out.written());
-        \\  "error": {}
+}
-        \\}
+
-    , out_alloc.writer.buffered());
+fn testLoadPage(url: [:0]const u8, writer: *std.Io.Writer) !*Server {
+    var server = try Server.init(testing.allocator, testing.test_app, writer);
+    errdefer server.deinit();
+
+    const page = try server.session.createPage();
+    try page.navigate(url, .{});
+
+    var runner = try server.session.runner(.{});
+    try runner.wait(.{ .ms = 2000 });
+    return server;
 }

src/testing.zig

@@ -415,7 +415,8 @@ fn runWebApiTest(test_file: [:0]const u8) !void {
     defer try_catch.deinit();
 
     try page.navigate(url, .{});
-    _ = test_session.wait(.{});
+    var runner = try test_session.runner(.{});
+    try runner.wait(.{ .ms = 2000 });
 
     test_browser.runMicrotasks();
 
@@ -439,7 +440,8 @@ pub fn pageTest(comptime test_file: []const u8) !*Page {
     );
 
     try page.navigate(url, .{});
-    _ = test_session.wait(.{});
+    var runner = try test_session.runner(.{});
+    try runner.wait(.{ .ms = 2000 });
     return page;
 }