fix(events): expose UIEvent pseudoTarget

moli-benchmark/wpt-cross-current/failed-cases.txt

@@ -3796,7 +3796,6 @@ trusted-types/trusted-types-reporting.html
 trusted-types/trusted-types-secondary-document.html
 trusted-types/trusted-types-svg-script-set-href.html
 uievents/order-of-events/focus-events/focus-automated-blink-webkit.html
-uievents/ui_event_pseudo_target.html
 url/a-element.html?exclude=(file|javascript|mailto)
 url/a-element.html?include=file
 url/a-element.html?include=javascript

moli-benchmark/wpt-cross-current/passed-cases.txt

@@ -7823,6 +7823,7 @@ uievents/legacy-domevents-tests/approved/stopPropagation.deferred.effect.html
 uievents/legacy-domevents-tests/submissions/Microsoft/converted/EventListener.dispatch.new.event.html
 uievents/legacy/Event-subclasses-init.html
 uievents/textInput/api.html
+uievents/ui_event_pseudo_target.html
 url/a-element-origin.html
 url/data-uri-fragment.html
 user-timing/clearMarks.html

moli-renderer-v8/src/context_bootstrap/event_template.rs

@@ -20,6 +20,7 @@ use super::{
         focus_event_related_target_getter_function, form_data_event_form_data_getter_function,
         mouse_event_related_target_getter_function, pointer_event_get_predicted_events_callback,
         submit_event_submitter_getter_function, track_event_track_getter_function,
+        ui_event_pseudo_target_getter_function,
     },
     selection_surface::document_get_selection_callback,
     specs::{ConstructorKind, ConstructorSpec},
@@ -185,6 +186,12 @@ struct FormDataEventTemplateAccessorsDeclaration {
 struct UiEventTemplateMethodsDeclaration {
     #[webapi(method = "initUIEvent", length = 0, callback = ui_event_init_callback)]
     init_ui_event: (),
+
+    #[webapi(
+        accessor_property = "pseudoTarget",
+        getter = ui_event_pseudo_target_getter_function
+    )]
+    pseudo_target: (),
 }
 
 #[derive(WebApiFunctionTemplate)]

moli-renderer-v8/src/context_bootstrap/events.rs

@@ -260,6 +260,42 @@ pub(crate) fn event_is_mouse_event<'s>(
     )
 }
 
+fn event_is_ui_event<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    event: v8::Local<'s, v8::Object>,
+) -> bool {
+    matches!(
+        event_subclass_kind(scope, event),
+        Some(
+            EventSubclassKind::UiEvent
+                | EventSubclassKind::FocusEvent
+                | EventSubclassKind::TextEvent
+                | EventSubclassKind::CompositionEvent
+                | EventSubclassKind::MouseEvent
+                | EventSubclassKind::DragEvent
+                | EventSubclassKind::KeyboardEvent
+                | EventSubclassKind::InputEvent
+                | EventSubclassKind::WheelEvent
+                | EventSubclassKind::PointerEvent
+                | EventSubclassKind::TouchEvent
+        )
+    )
+}
+
+pub(super) fn ui_event_pseudo_target_getter_function<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    args: v8::FunctionCallbackArguments<'s>,
+    mut rv: v8::ReturnValue<'_, v8::Value>,
+) {
+    if !event_is_ui_event(scope, args.this()) {
+        throw_type_error(scope, "Illegal invocation");
+        return;
+    }
+    // Moli does not currently synthesize UI events whose origin is a CSS
+    // pseudo-element, so every supported UIEvent has the default null value.
+    rv.set(v8::null(scope).into());
+}
+
 fn event_related_target_value<'s>(
     scope: &mut v8::PinScope<'s, '_>,
     event: v8::Local<'s, v8::Object>,

moli-renderer-v8/src/script_vm/tests/browser_api/events_selection_storage.rs

@@ -2177,6 +2177,63 @@ fn event_timestamp_uses_performance_origin_and_safe_resolution() {
         r#"{"hasGetter":true,"getterName":"get timeStamp","getterLength":0,"enumerable":true,"configurable":true,"hasOwnTimeStamp":false,"withinNowRange":true,"getterMatchesOwnValue":true,"safeResolution":true}"#
     );
 }
+
+#[test]
+fn ui_event_pseudo_target_is_declared_once_and_inherited() {
+    let mut vm = new_storage_test_vm("https://ui-event-pseudo-target.test/");
+
+    let result = vm
+        .eval(
+            r#"
+            (() => {
+              const descriptor =
+                Object.getOwnPropertyDescriptor(UIEvent.prototype, "pseudoTarget");
+              const getter = descriptor.get;
+              const thrownName = receiver => {
+                try {
+                  getter.call(receiver);
+                  return "none";
+                } catch (error) {
+                  return error && error.name;
+                }
+              };
+              const textEvent = document.createEvent("TextEvent");
+
+              return JSON.stringify({
+                descriptor: [
+                  getter.name,
+                  getter.length,
+                  typeof descriptor.set,
+                  descriptor.enumerable,
+                  descriptor.configurable
+                ],
+                placement: [
+                  Object.prototype.hasOwnProperty.call(Event.prototype, "pseudoTarget"),
+                  Object.prototype.hasOwnProperty.call(UIEvent.prototype, "pseudoTarget"),
+                  Object.prototype.hasOwnProperty.call(MouseEvent.prototype, "pseudoTarget"),
+                  "pseudoTarget" in MouseEvent.prototype
+                ],
+                values: [
+                  new UIEvent("ui").pseudoTarget,
+                  new MouseEvent("mouse").pseudoTarget,
+                  getter.call(textEvent)
+                ],
+                illegalReceivers: [
+                  thrownName(new Event("event")),
+                  thrownName({})
+                ]
+              });
+            })()
+            "#,
+        )
+        .expect("UIEvent pseudoTarget prototype probe should evaluate");
+
+    assert_eq!(
+        result,
+        r#"{"descriptor":["get pseudoTarget",0,"undefined",true,true],"placement":[false,true,false,true],"values":[null,null,null],"illegalReceivers":["TypeError","TypeError"]}"#
+    );
+}
+
 #[test]
 fn performance_entry_accessors_return_entries_sorted_by_start_time() {
     let mut vm = new_storage_test_vm("https://performance-entry-order.test/");