ES6: Add support for Map.prototype.forEach and Set.prototype.forEach

src/factory.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "factory.h"
 
 #include "isolate-inl.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 1978 matching lines @@
   if (String::Equals(name, nan_string())) return nan_value();
   if (String::Equals(name, infinity_string())) return infinity_value();
   return Handle<Object>::null();
 }
 
 
 Handle<Object> Factory::ToBoolean(bool value) {
   return value ? true_value() : false_value();
 }
 
+Handle<JSObject> Factory::CreateIteratorResultObject(Handle<Object> value,
+                                                     bool done) {
+  Handle<Map> map(isolate()->native_context()->iterator_result_map());
+  Handle<JSObject> result = NewJSObjectFromMap(map, NOT_TENURED, false);
+  JSObject::SetProperty(result, value_string(), value, NONE, SLOPPY).Assert();

[adamk, 2014/04/14 21:33:01]

I think you can skip all the JSObject machinery here and set these properties
directly into the object. I believe the syntax is:

result->InObjectPropertyAtPut(
    JSGeneratorObject::kResultValuePropertyIndex, value);
result->InObjectPropertyAtPut(
    JSGeneratorObject::kResultDonePropertyIndex, ToBoolean(done));

Seems like we might want to move those constants out of JSGeneratorObject and
into another class...not sure what the v8 folks would want.

[arv (Not doing code reviews), 2014/04/14 21:41:56]

Done.

+  JSObject::SetProperty(
+      result, done_string(), ToBoolean(done), NONE, SLOPPY).Assert();
+  return result;
+}
+
 } }  // namespace v8::internal