LibWeb: Implement EventTarget.dispatchEvent

Used by Web Platform Tests to test events

Userland/Libraries/LibWeb/CodeGenerators/WrapperGenerator.cpp

@@ -499,6 +499,8 @@ static bool is_wrappable_type(const IDL::Type& type)
         return true;
     if (type.name.ends_with("Element"))
         return true;
+    if (type.name.ends_with("Event"))
+        return true;
     if (type.name == "ImageData")
         return true;
     return false;

Userland/Libraries/LibWeb/DOM/EventTarget.cpp

@@ -5,6 +5,7 @@
  */
 
 #include <LibWeb/Bindings/ScriptExecutionContext.h>
+#include <LibWeb/DOM/Event.h>
 #include <LibWeb/DOM/EventListener.h>
 #include <LibWeb/DOM/EventTarget.h>
 
@@ -53,4 +54,18 @@ void EventTarget::remove_from_event_listener_list(NonnullRefPtr<EventListener> l
     });
 }
 
+// https://dom.spec.whatwg.org/#dom-eventtarget-dispatchevent
+ExceptionOr<bool> EventTarget::dispatch_event_binding(NonnullRefPtr<Event> event)
+{
+    if (event->dispatched())
+        return DOM::InvalidStateError::create("The event is already being dispatched.");
+
+    if (!event->initialized())
+        return DOM::InvalidStateError::create("Cannot dispatch an uninitialized event.");
+
+    event->set_is_trusted(false);
+
+    return dispatch_event(event);
+}
+
 }

Userland/Libraries/LibWeb/DOM/EventTarget.h

@@ -11,6 +11,7 @@
 #include <AK/Noncopyable.h>
 #include <AK/Vector.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/DOM/ExceptionOr.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::DOM {
@@ -31,6 +32,8 @@ public:
     void remove_from_event_listener_list(NonnullRefPtr<EventListener>);
 
     virtual bool dispatch_event(NonnullRefPtr<Event>) = 0;
+    ExceptionOr<bool> dispatch_event_binding(NonnullRefPtr<Event>);
+
     virtual JS::Object* create_wrapper(JS::GlobalObject&) = 0;
     Bindings::ScriptExecutionContext* script_execution_context() { return m_script_execution_context; }
 

Userland/Libraries/LibWeb/DOM/EventTarget.idl

@@ -1,6 +1,9 @@
 interface EventTarget {
 
+    // FIXME: Both of these should take in options
     undefined addEventListener(DOMString type, EventListener? callback);
     undefined removeEventListener(DOMString type, EventListener? callback);
 
+    [ImplementedAs=dispatch_event_binding] boolean dispatchEvent(Event event);
+
 };