Arguments object has @@iterator

src/array-iterator.js

 // Copyright 2013 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.
 
 'use strict';
 
 
 // This file relies on the fact that the following declaration has been made
 // in runtime.js:
 // var $Array = global.Array;
@@ skipping 108 matching lines @@
 function ExtendArrayPrototype() {
   %CheckIsBootstrapping();
 
   InstallFunctions($Array.prototype, DONT_ENUM, $Array(
     'entries', ArrayEntries,
     'values', ArrayValues,
     'keys', ArrayKeys
   ));
 }
 ExtendArrayPrototype();
+
+
+function ArgumentsIteratorGetter() {
+  return ArrayValues;
+}
+
+
+function ArgumentsIteratorSetter(val) {
+  ObjectDefineProperty(this, symbolIterator, {
+    value: val,
+    writable: true,
+    enumerable: false,
+    configurable: true
+  });
+}
+
+
+function ExtendArgumentsBoilerplateObjects() {
+  %CheckIsBootstrapping();
+
+  for (var i = 0; i < 3; i++) {
+    var boilerplate = %GetArgumentsBoilerplateObject(i);
+    ObjectDefineProperty(boilerplate, symbolIterator, {
+      get: ArgumentsIteratorGetter,

[arv (Not doing code reviews), 2014/06/25 15:55:05]

It is not clear to me why this cannot be a data property?

With the current code, what does the descriptor look like for?

Object.getOwnPropertyDescriptor(arguments, Symbol.iterator)

+      set: ArgumentsIteratorSetter,
+      enumerable: false,
+      configurable: true
+    });
+  }
+}
+ExtendArgumentsBoilerplateObjects();