API support for promises

include/v8.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1394 matching lines @@
   /**
    * Returns true if this value is a NativeError.
    */
   bool IsNativeError() const;
 
   /**
    * Returns true if this value is a RegExp.
    */
   bool IsRegExp() const;
 
+  /**
+   * Returns true if this value is a Promise.
+   * This is an experimental feature. Only works with --harmony flag.

[Sven Panne, 2014/03/11 11:44:05]

Hopefully this works without --harmony, too (and returns false in that case).

[rossberg, 2014/03/11 16:08:40]

Done.

+   */
+  bool IsPromise() const;
 
   /**
    * Returns true if this value is an ArrayBuffer.
    * This is an experimental feature.
    */
   bool IsArrayBuffer() const;
 
   /**
    * Returns true if this value is an ArrayBufferView.
    * This is an experimental feature.
@@ skipping 1104 matching lines @@
 
   ScriptOrigin GetScriptOrigin() const;
   V8_INLINE static Function* Cast(Value* obj);
   static const int kLineOffsetNotFound;
 
  private:
   Function();
   static void CheckCast(Value* obj);
 };
 
+
+/**
+ * An instance of the built-in Promise constructor (ES6 draft).
+ * This API is experimental. Only works with --harmony flag.
+ */
+class V8_EXPORT Promise : public Object {
+ public:
+  /**
+   * Create a new Promise in pending state.
+   */
+  static Local<Promise> New(Isolate* isolate);
+
+  /**
+   * Resolve/reject a promise with a given value.
+   * Ignored if the promise is not unresolved.
+   */
+  void Resolve(Handle<Value> value);
+  void Reject(Handle<Value> value);
+

[yhirano, 2014/03/11 11:46:42]

Can we have Then, too?

[rossberg, 2014/03/11 16:08:40]

Will that actually be useful on the API side? (I'm not even sure about
Chain/Catch. Let's keep the API minimal for now.)

+  /**
+   * Register a resolution/rejection handler with a promise.
+   * The handler is given the respective resolution/rejection value as
+   * an argument. If the promise is already resolved/rejected, the handler is
+   * invoked at the end of turn.
+   */
+  Local<Promise> Chain(Handle<Function> handler);
+  Local<Promise> Catch(Handle<Function> handler);
+
+  V8_INLINE static Promise* Cast(Value* obj);
+
+ private:
+  Promise();
+  static void CheckCast(Value* obj);
+};
+
+
 #ifndef V8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT
 // The number of required internal fields can be defined by embedder.
 #define V8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT 2
 #endif
 
 /**
  * An instance of the built-in ArrayBuffer constructor (ES6 draft 15.13.5).
  * This API is experimental and may change significantly.
  */
 class V8_EXPORT ArrayBuffer : public Object {
@@ skipping 3633 matching lines @@
 
 
 Array* Array::Cast(v8::Value* value) {
 #ifdef V8_ENABLE_CHECKS
   CheckCast(value);
 #endif
   return static_cast<Array*>(value);
 }
 
 
+Promise* Promise::Cast(v8::Value* value) {
+#ifdef V8_ENABLE_CHECKS
+  CheckCast(value);
+#endif
+  return static_cast<Promise*>(value);
+}
+
+
 ArrayBuffer* ArrayBuffer::Cast(v8::Value* value) {
 #ifdef V8_ENABLE_CHECKS
   CheckCast(value);
 #endif
   return static_cast<ArrayBuffer*>(value);
 }
 
 
 ArrayBufferView* ArrayBufferView::Cast(v8::Value* value) {
 #ifdef V8_ENABLE_CHECKS
@@ skipping 255 matching lines @@
  */
 
 
 }  // namespace v8
 
 
 #undef TYPE_CHECK
 
 
 #endif  // V8_H_