Implement Array.from()

test/mjsunit/harmony/array-from-generators.js

+// 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.
+
+// Flags: --harmony-arrays --harmony-generators
+(function() {
+
+assertEquals(1, Array.from.length);
+
+function testArrayFrom(thisArg, constructor) {
+  assertArrayLikeEquals(Array.from.call(thisArg, generator()), ['a', 'b', 'c'], constructor);
+}
+
+testArrayFrom(Array, Array);
+testArrayFrom(null, Array);
+testArrayFrom({}, Array);
+testArrayFrom(Object, Object);
+testArrayFrom(Other, Other);
+
+function Other() {}
+
+function* generator() {

[arv (Not doing code reviews), 2014/09/05 18:04:54]

Move this up, before the first usage.

+  yield 'a';
+  yield 'b';
+  yield 'c';
+}
+
+function assertArrayLikeEquals(value, expected, type) {
+  assertInstanceof(value, type);
+  assertEquals(expected.length, value.length);
+  for (var i=0; i<value.length; ++i) {
+    assertEquals(expected[i], value[i]);
+  }
+}
+
+})();