Enable using custom events when emitting

atom/browser/api/event_emitter.cc

@@ -37,9 +37,8 @@ v8::Local<v8::Object> CreateEventObject(v8::Isolate* isolate) {
 EventEmitter::EventEmitter() {
 }
 
-v8::Local<v8::Object> EventEmitter::CreateJSEvent(v8::Isolate* isolate,
-                                                  content::WebContents* sender,
-                                                  IPC::Message* message) {
+v8::Local<v8::Object> EventEmitter::CreateJSEvent(
+    v8::Isolate* isolate, content::WebContents* sender, IPC::Message* message) {
   v8::Local<v8::Object> event;
   bool use_native_event = sender && message;
 
@@ -54,4 +53,12 @@ v8::Local<v8::Object> EventEmitter::CreateJSEvent(v8::Isolate* isolate,
   return event;
 }
 
+v8::Local<v8::Object> EventEmitter::CreateCustomEvent(
+    v8::Isolate* isolate, v8::Local<v8::Object> custom_event) {
+  v8::Local<v8::Object> event = CreateEventObject(isolate);
+  event->SetPrototype(custom_event->CreationContext(), custom_event);
+  mate::Dictionary(isolate, event).Set("sender", GetWrapper(isolate));
+  return event;
+}
+
 }  // namespace mate

atom/browser/api/event_emitter.h

@@ -25,6 +25,14 @@ class EventEmitter : public Wrappable {
  public:
   typedef std::vector<v8::Local<v8::Value>> ValueArray;
 
+  // this.emit(name, event, args...);
+  template<typename... Args>
+  bool EmitCustomEvent(const base::StringPiece& name,
+                       v8::Local<v8::Object> event,
+                       const Args&... args) {
+    return EmitWithEvent(name, CreateCustomEvent(isolate(), event), args...);
+  }
+
   // this.emit(name, new Event(), args...);
   template<typename... Args>
   bool Emit(const base::StringPiece& name, const Args&... args) {
@@ -37,21 +45,31 @@ class EventEmitter : public Wrappable {
                       content::WebContents* sender,
                       IPC::Message* message,
                       const Args&... args) {
-    v8::Locker locker(isolate());
-    v8::HandleScope handle_scope(isolate());
     v8::Local<v8::Object> event = CreateJSEvent(isolate(), sender, message);
-    EmitEvent(isolate(), GetWrapper(isolate()), name, event, args...);
-    return event->Get(
-        StringToV8(isolate(), "defaultPrevented"))->BooleanValue();
+    return EmitWithEvent(name, event, args...);
   }
 
  protected:
   EventEmitter();
 
  private:
+  // this.emit(name, event, args...);
+  template<typename... Args>
+  bool EmitWithEvent(const base::StringPiece& name,
+                     v8::Local<v8::Object> event,
+                     const Args&... args) {
+    v8::Locker locker(isolate());
+    v8::HandleScope handle_scope(isolate());
+    EmitEvent(isolate(), GetWrapper(isolate()), name, event, args...);
+    return event->Get(
+        StringToV8(isolate(), "defaultPrevented"))->BooleanValue();
+  }
+
   v8::Local<v8::Object> CreateJSEvent(v8::Isolate* isolate,
                                       content::WebContents* sender,
                                       IPC::Message* message);
+  v8::Local<v8::Object> CreateCustomEvent(
+      v8::Isolate* isolate, v8::Local<v8::Object> event);
 
   DISALLOW_COPY_AND_ASSIGN(EventEmitter);
 };