Implement %TypedArray%.reverse

test/mjsunit/harmony/typedarray-reverse.js

+// Copyright 2015 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
+
+function ArrayMaker(x) {
+  return x;
+}
+ArrayMaker.prototype = Array.prototype;
+
+var arrayConstructors = [
+  Uint8Array,
+  Int8Array,
+  Uint16Array,
+  Int16Array,
+  Uint32Array,
+  Int32Array,
+  Uint8ClampedArray,
+  Float32Array,
+  Float64Array,
+  ArrayMaker  // Also test arrays
+];
+
+function assertArrayLikeEquals(value, expected, type) {
+  assertEquals(value.__proto__, type.prototype);
+  assertEquals(expected.length, value.length);
+  for (var i = 0; i < value.length; ++i) {
+    assertEquals(expected[i], value[i]);
+  }
+}
+
+for (var constructor of arrayConstructors) {
+  // Test reversing both even and odd length arrays
+  var a = new constructor([1, 2, 3]);
+  assertArrayLikeEquals(a.reverse(), [3, 2, 1], constructor);
+  assertArrayLikeEquals(a, [3, 2, 1], constructor);
+
+  a = new constructor([1, 2, 3, 4]);
+  assertArrayLikeEquals(a.reverse(), [4, 3, 2, 1], constructor);
+  assertArrayLikeEquals(a, [4, 3, 2, 1], constructor);
+
+  if (constructor != ArrayMaker) {
+    // Cannot be called on objects which are not TypedArrays
+    assertThrows(function () { a.reverse.call({ length: 0 }); }, TypeError);
+  } else {
+    // Array.reverse works on array-like objects
+    var x = { length: 2, 1: 5 };
+    a.reverse.call(x);
+    assertEquals(2, x.length);
+    assertFalse(Object.hasOwnProperty(x, '1'));
+    assertEquals(5, x[0]);
+  }
+
+  assertEquals(0, a.reverse.length);
+}