From 5f459c090127a60f9d02132dd5d250c15e482b3e Mon Sep 17 00:00:00 2001
From: egrs <egrs@users.noreply.github.com>
Date: Sat, 21 Feb 2026 14:43:41 +0100
Subject: [PATCH 1/2] cache document.implementation for object identity
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

getImplementation() now returns a cached *DOMImplementation pointer
per Document, matching the getStyleSheets() pattern. This ensures
document.implementation === document.implementation holds true.

Flips dom/nodes/Document-implementation.html (1/2 → 2/2).
---
 src/browser/webapi/Document.zig | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/browser/webapi/Document.zig b/src/browser/webapi/Document.zig
index 85f9c35f..4ee70ded 100644
--- a/src/browser/webapi/Document.zig
+++ b/src/browser/webapi/Document.zig
@@ -52,6 +52,7 @@ _elements_by_id: std.StringHashMapUnmanaged(*Element) = .empty,
 _removed_ids: std.StringHashMapUnmanaged(void) = .empty,
 _active_element: ?*Element = null,
 _style_sheets: ?*StyleSheetList = null,
+_implementation: ?*DOMImplementation = null,
 _write_insertion_point: ?*Node = null,
 _script_created_parser: ?Parser.Streaming = null,
 _adopted_style_sheets: ?js.Object.Global = null,
@@ -272,8 +273,11 @@ pub fn querySelectorAll(self: *Document, input: String, page: *Page) !*Selector.
     return Selector.querySelectorAll(self.asNode(), input.str(), page);
 }
 
-pub fn getImplementation(_: *const Document) DOMImplementation {
-    return .{};
+pub fn getImplementation(self: *Document, page: *Page) !*DOMImplementation {
+    if (self._implementation) |impl| return impl;
+    const impl = try page._factory.create(DOMImplementation{});
+    self._implementation = impl;
+    return impl;
 }
 
 pub fn createDocumentFragment(self: *Document, page: *Page) !*Node.DocumentFragment {
@@ -726,6 +730,7 @@ pub fn open(self: *Document, page: *Page) !*Document {
     self._elements_by_id.clearAndFree(page.arena);
     self._active_element = null;
     self._style_sheets = null;
+    self._implementation = null;
     self._ready_state = .loading;
 
     self._script_created_parser = Parser.Streaming.init(page.arena, doc_node, page);

From 39f9209374afbe22c518b5ee6c58fcb0646d93d4 Mon Sep 17 00:00:00 2001
From: egrs <egrs@users.noreply.github.com>
Date: Sat, 21 Feb 2026 14:43:45 +0100
Subject: [PATCH 2/2] fix file input value getter/setter per spec
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- getValue() returns "" for file inputs regardless of value attribute
- setValue("") is a no-op for file inputs (was throwing)
- setValue(non-empty) still throws InvalidStateError
- add _setValue bridge wrapper for [LegacyNullToEmptyString]: null → ""

Flips html/semantics/forms/the-input-element/valueMode.html (38/40 → 40/40).
---
 src/browser/webapi/element/html/Input.zig | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/browser/webapi/element/html/Input.zig b/src/browser/webapi/element/html/Input.zig
index 0928a9c9..831c5383 100644
--- a/src/browser/webapi/element/html/Input.zig
+++ b/src/browser/webapi/element/html/Input.zig
@@ -125,6 +125,7 @@ pub fn setType(self: *Input, typ: []const u8, page: *Page) !void {
 }
 
 pub fn getValue(self: *const Input) []const u8 {
+    if (self._input_type == .file) return "";
     return self._value orelse self._default_value orelse switch (self._input_type) {
         .checkbox, .radio => "on",
         else => "",
@@ -132,8 +133,9 @@ pub fn getValue(self: *const Input) []const u8 {
 }
 
 pub fn setValue(self: *Input, value: []const u8, page: *Page) !void {
-    // File inputs cannot have their value set programmatically for security reasons
+    // File inputs: setting to empty string is a no-op, anything else throws
     if (self._input_type == .file) {
+        if (value.len == 0) return;
         return error.InvalidStateError;
     }
     // This should _not_ call setAttribute. It updates the current state only
@@ -846,9 +848,17 @@ pub const JsApi = struct {
         pub var class_id: bridge.ClassId = undefined;
     };
 
+    /// Handles [LegacyNullToEmptyString]: null → "" per HTML spec.
+    fn setValueFromJS(self: *Input, js_value: js.Value, page: *Page) !void {
+        if (js_value.isNull()) {
+            return self.setValue("", page);
+        }
+        return self.setValue(try js_value.toZig([]const u8), page);
+    }
+
     pub const onselectionchange = bridge.accessor(Input.getOnSelectionChange, Input.setOnSelectionChange, .{});
     pub const @"type" = bridge.accessor(Input.getType, Input.setType, .{});
-    pub const value = bridge.accessor(Input.getValue, Input.setValue, .{ .dom_exception = true });
+    pub const value = bridge.accessor(Input.getValue, setValueFromJS, .{ .dom_exception = true });
     pub const defaultValue = bridge.accessor(Input.getDefaultValue, Input.setDefaultValue, .{});
     pub const checked = bridge.accessor(Input.getChecked, Input.setChecked, .{});
     pub const defaultChecked = bridge.accessor(Input.getDefaultChecked, Input.setDefaultChecked, .{});