LibWeb: Add TrustedTypePolicy class

It is mostly a skeleton with no actual implementation.

Libraries/LibWeb/CMakeLists.txt

@@ -897,6 +897,7 @@ set(SOURCES
     SVG/TagNames.cpp
     SVG/ViewBox.cpp
     TrustedTypes/TrustedHTML.cpp
+    TrustedTypes/TrustedTypePolicy.cpp
     TrustedTypes/TrustedTypePolicyFactory.cpp
     UIEvents/CompositionEvent.cpp
     UIEvents/EventNames.cpp

Libraries/LibWeb/Forward.h

@@ -1221,6 +1221,8 @@ ErrorOr<Web::UniqueNodeID> decode(Decoder&);
 namespace Web::TrustedTypes {
 
 class TrustedHTML;
+class TrustedTypePolicy;
 class TrustedTypePolicyFactory;
+struct TrustedTypePolicyOptions;
 
 }

Libraries/LibWeb/TrustedTypes/TrustedTypePolicy.cpp

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2025, Miguel Sacristán Izcue <miguel_tete17@hotmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibWeb/TrustedTypes/TrustedTypePolicy.h>
+
+#include <LibGC/Ptr.h>
+#include <LibJS/Runtime/Realm.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+
+namespace Web::TrustedTypes {
+
+GC_DEFINE_ALLOCATOR(TrustedTypePolicy);
+
+TrustedTypePolicy::TrustedTypePolicy(JS::Realm& realm)
+    : PlatformObject(realm)
+{
+}
+
+void TrustedTypePolicy::initialize(JS::Realm& realm)
+{
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(TrustedTypePolicy);
+    Base::initialize(realm);
+}
+
+}

Libraries/LibWeb/TrustedTypes/TrustedTypePolicy.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2025, Miguel Sacristán Izcue <miguel_tete17@hotmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibJS/Forward.h>
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Bindings/TrustedTypePolicyPrototype.h>
+
+namespace Web::TrustedTypes {
+
+struct TrustedTypePolicyOptions {
+    GC::Root<WebIDL::CallbackType> create_html;
+    GC::Root<WebIDL::CallbackType> create_script;
+    GC::Root<WebIDL::CallbackType> create_script_url;
+};
+
+class TrustedTypePolicy final : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(TrustedTypePolicy, Bindings::PlatformObject);
+    GC_DECLARE_ALLOCATOR(TrustedTypePolicy);
+
+public:
+    virtual ~TrustedTypePolicy() override = default;
+
+private:
+    explicit TrustedTypePolicy(JS::Realm&);
+    virtual void initialize(JS::Realm&) override;
+};
+
+}

Libraries/LibWeb/TrustedTypes/TrustedTypePolicy.idl

@@ -0,0 +1,18 @@
+// https://w3c.github.io/trusted-types/dist/spec/#trusted-type-policy
+[Exposed=(Window,Worker)]
+interface TrustedTypePolicy {
+    [FIXME] readonly attribute DOMString name;
+    [FIXME] TrustedHTML createHTML(DOMString input, any... arguments);
+    [FIXME] TrustedScript createScript(DOMString input, any... arguments);
+    [FIXME] TrustedScriptURL createScriptURL(DOMString input, any... arguments);
+};
+
+// https://w3c.github.io/trusted-types/dist/spec/#trusted-type-policy-options
+dictionary TrustedTypePolicyOptions {
+    CreateHTMLCallback createHTML;
+    CreateScriptCallback createScript;
+    CreateScriptURLCallback createScriptURL;
+};
+callback CreateHTMLCallback = DOMString? (DOMString input, any... arguments);
+callback CreateScriptCallback = DOMString? (DOMString input, any... arguments);
+callback CreateScriptURLCallback = USVString? (DOMString input, any... arguments);

Libraries/LibWeb/idl_files.cmake

@@ -329,6 +329,7 @@ libweb_js_bindings(Streams/WritableStream)
 libweb_js_bindings(Streams/WritableStreamDefaultController)
 libweb_js_bindings(Streams/WritableStreamDefaultWriter)
 libweb_js_bindings(TrustedTypes/TrustedHTML)
+libweb_js_bindings(TrustedTypes/TrustedTypePolicy)
 libweb_js_bindings(TrustedTypes/TrustedTypePolicyFactory)
 libweb_js_bindings(SVG/SVGAElement)
 libweb_js_bindings(SVG/SVGAnimatedEnumeration)

Meta/Lagom/Tools/CodeGenerators/LibWeb/BindingsGenerator/IDLGenerators.cpp

@@ -117,6 +117,7 @@ static bool is_platform_object(Type const& type)
         "TextTrack"sv,
         "TimeRanges"sv,
         "TrustedHTML"sv,
+        "TrustedTypePolicy"sv,
         "TrustedTypePolicyFactory"sv,
         "URLSearchParams"sv,
         "VTTRegion"sv,

Tests/LibWeb/Text/expected/all-window-properties.txt

@@ -433,6 +433,7 @@ TransformStreamDefaultController
 TransitionEvent
 TreeWalker
 TrustedHTML
+TrustedTypePolicy
 TrustedTypePolicyFactory
 TypeError
 UIEvent