LibWeb/CSS: Add the TransitionEvent type

Author: https://github.com/LucasChollet
Commit: 55b4a983a7
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/3024

Libraries/LibWeb/CMakeLists.txt

@@ -170,6 +170,7 @@ set(SOURCES
     CSS/SystemColor.cpp
     CSS/Time.cpp
     CSS/Transformation.cpp
+    CSS/TransitionEvent.cpp
     CSS/VisualViewport.cpp
     Cookie/Cookie.cpp
     Cookie/ParsedCookie.cpp

Libraries/LibWeb/CSS/TransitionEvent.cpp

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2024, Lucas Chollet <lucas.chollet@serenityos.org>.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "TransitionEvent.h"
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/Bindings/TransitionEventPrototype.h>
+
+namespace Web::CSS {
+
+GC_DEFINE_ALLOCATOR(TransitionEvent);
+
+GC::Ref<TransitionEvent> TransitionEvent::create(JS::Realm& realm, FlyString const& type, TransitionEventInit const& event_init)
+{
+    auto event = realm.create<TransitionEvent>(realm, type, event_init);
+    event->set_is_trusted(true);
+    return event;
+}
+
+GC::Ref<TransitionEvent> TransitionEvent::construct_impl(JS::Realm& realm, FlyString const& type, TransitionEventInit const& event_init)
+{
+    return realm.create<TransitionEvent>(realm, type, event_init);
+}
+
+TransitionEvent::TransitionEvent(JS::Realm& realm, FlyString const& type, TransitionEventInit const& event_init)
+    : DOM::Event(realm, type, event_init)
+    , m_property_name(event_init.property_name)
+    , m_elapsed_time(event_init.elapsed_time)
+    , m_pseudo_element(event_init.pseudo_element)
+{
+}
+
+TransitionEvent::~TransitionEvent() = default;
+
+void TransitionEvent::initialize(JS::Realm& realm)
+{
+    Base::initialize(realm);
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(TransitionEvent);
+}
+
+}

Libraries/LibWeb/CSS/TransitionEvent.h

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2024, Lucas Chollet <lucas.chollet@serenityos.org>.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibWeb/DOM/Event.h>
+
+namespace Web::CSS {
+
+struct TransitionEventInit : public DOM::EventInit {
+    String property_name {};
+    double elapsed_time = 0.0;
+    String pseudo_element {};
+};
+
+class TransitionEvent final : public DOM::Event {
+    WEB_PLATFORM_OBJECT(TransitionEvent, DOM::Event);
+    GC_DECLARE_ALLOCATOR(TransitionEvent);
+
+public:
+    [[nodiscard]] static GC::Ref<TransitionEvent> create(JS::Realm&, FlyString const& event_name, TransitionEventInit const& = {});
+    [[nodiscard]] static GC::Ref<TransitionEvent> construct_impl(JS::Realm&, FlyString const& event_name, TransitionEventInit const& = {});
+
+    virtual ~TransitionEvent() override;
+
+    String const& property_name() const { return m_property_name; }
+    double elapsed_time() const { return m_elapsed_time; }
+    String const& pseudo_element() const { return m_pseudo_element; }
+
+private:
+    TransitionEvent(JS::Realm&, FlyString const& event_name, TransitionEventInit const& event_init);
+
+    virtual void initialize(JS::Realm&) override;
+
+    String m_property_name {};
+    double m_elapsed_time {};
+    String m_pseudo_element {};
+};
+}

Libraries/LibWeb/CSS/TransitionEvent.idl

@@ -0,0 +1,16 @@
+#import <DOM/Event.idl>
+
+// https://drafts.csswg.org/css-transitions/#transitionevent
+[Exposed=Window]
+interface TransitionEvent : Event {
+    constructor(CSSOMString type, optional TransitionEventInit transitionEventInitDict = {});
+    readonly attribute CSSOMString propertyName;
+    readonly attribute double elapsedTime;
+    readonly attribute CSSOMString pseudoElement;
+};
+
+dictionary TransitionEventInit : EventInit {
+    CSSOMString propertyName = "";
+    double elapsedTime = 0.0;
+    CSSOMString pseudoElement = "";
+};

Libraries/LibWeb/idl_files.cmake

@@ -46,6 +46,7 @@ libweb_js_bindings(CSS/Screen)
 libweb_js_bindings(CSS/ScreenOrientation)
 libweb_js_bindings(CSS/StyleSheet)
 libweb_js_bindings(CSS/StyleSheetList)
+libweb_js_bindings(CSS/TransitionEvent)
 libweb_js_bindings(CSS/VisualViewport)
 libweb_js_bindings(DOM/AbstractRange)
 libweb_js_bindings(DOM/Attr)