ES6: Add support for Map and Set Iterator

src/collection-iterator.js

Index: src/collection-iterator.js
diff --git a/src/collection-iterator.js b/src/collection-iterator.js
new file mode 100644
index 0000000000000000000000000000000000000000..31caaee45c865355a68259993c0f3d131c07f006
--- /dev/null
+++ b/src/collection-iterator.js
@@ -0,0 +1,164 @@
+// 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.
+
+'use strict';
+
+
+// This file relies on the fact that the following declaration has been made
+// in runtime.js:
+// var $Set = global.Set;
+// var $Map = global.Map;
+
+
+function SetIteratorConstructor(set, kind) {
+  %SetIteratorInitialize(this, set, kind);
+}
+
+
+function SetIteratorNextJS() {
+  if (!IS_SET_ITERATOR(this)) {
+    throw MakeTypeError('incompatible_method_receiver',
+                        ['Set Iterator.prototype.next', this]);
+  }
+  return %SetIteratorNext(this);
+}
+
+
+function SetIteratorSymbolIterator() {
+  return this;
+}
+
+
+function SetEntries() {
+  if (!IS_SET(this)) {
+    throw MakeTypeError('incompatible_method_receiver',
+                        ['Set.prototype.entries', this]);
+  }
+  return new SetIterator(this, ITERATOR_KIND_ENTRIES);
+}
+
+
+function SetValues() {
+  if (!IS_SET(this)) {
+    throw MakeTypeError('incompatible_method_receiver',
+                        ['Set.prototype.values', this]);
+  }
+  return new SetIterator(this, ITERATOR_KIND_VALUES);
+}
+
+
+function SetUpSetIterator() {
+  %CheckIsBootstrapping();
+
+  %SetCode(SetIterator, SetIteratorConstructor);
+  %FunctionSetPrototype(SetIterator, new $Object());
+  %FunctionSetInstanceClassName(SetIterator, 'Set Iterator');
+  InstallFunctions(SetIterator.prototype, DONT_ENUM, $Array(
+    'next', SetIteratorNextJS
+  ));
+
+  %FunctionSetName(SetIteratorSymbolIterator, '[Symbol.iterator]');
+  %SetProperty(SetIterator.prototype, InternalSymbol('Symbol.iterator'),
+      SetIteratorSymbolIterator,
+      DONT_ENUM);
+}
+
+SetUpSetIterator();
+
+
+function ExtendSetPrototype() {
+  %CheckIsBootstrapping();
+
+  InstallFunctions($Set.prototype, DONT_ENUM, $Array(
+    'entries', SetEntries,
+    'values', SetValues
+  ));
+
+  %SetProperty($Set.prototype, InternalSymbol('Symbol.iterator'), SetValues,
+      DONT_ENUM);
+}
+
+ExtendSetPrototype();
+
+
+
+function MapIteratorConstructor(map, kind) {
+  %MapIteratorInitialize(this, map, kind);
+}
+
+
+function MapIteratorSymbolIterator() {
+  return this;
+}
+
+
+function MapIteratorNextJS() {
+  if (!IS_MAP_ITERATOR(this)) {
+    throw MakeTypeError('incompatible_method_receiver',
+                        ['Map Iterator.prototype.next', this]);
+  }
+  return %MapIteratorNext(this);
+}
+
+
+function MapEntries() {
+  if (!IS_MAP(this)) {
+    throw MakeTypeError('incompatible_method_receiver',
+                        ['Map.prototype.entries', this]);
+  }
+  return new MapIterator(this, ITERATOR_KIND_ENTRIES);
+}
+
+
+function MapKeys() {
+  if (!IS_MAP(this)) {
+    throw MakeTypeError('incompatible_method_receiver',
+                        ['Map.prototype.keys', this]);
+  }
+  return new MapIterator(this, ITERATOR_KIND_KEYS);
+}
+
+
+function MapValues() {
+  if (!IS_MAP(this)) {
+    throw MakeTypeError('incompatible_method_receiver',
+                        ['Map.prototype.values', this]);
+  }
+  return new MapIterator(this, ITERATOR_KIND_VALUES);
+}
+
+
+function SetUpMapIterator() {
+  %CheckIsBootstrapping();
+
+  %SetCode(MapIterator, MapIteratorConstructor);
+  %FunctionSetPrototype(MapIterator, new $Object());
+  %FunctionSetInstanceClassName(MapIterator, 'Map Iterator');
+  InstallFunctions(MapIterator.prototype, DONT_ENUM, $Array(
+    'next', MapIteratorNextJS
+  ));
+
+  %FunctionSetName(MapIteratorSymbolIterator, '[Symbol.iterator]');
+  %SetProperty(MapIterator.prototype, InternalSymbol('Symbol.iterator'),
+      MapIteratorSymbolIterator,
+      DONT_ENUM);
+}
+
+SetUpMapIterator();
+
+
+function ExtendMapPrototype() {
+  %CheckIsBootstrapping();
+
+  InstallFunctions($Map.prototype, DONT_ENUM, $Array(
+    'entries', MapEntries,
+    'keys', MapKeys,
+    'values', MapValues
+  ));
+
+  %SetProperty($Map.prototype, InternalSymbol('Symbol.iterator'), MapEntries,
+      DONT_ENUM);
+}
+
+ExtendMapPrototype();