ES6: Add support for Array.prototype.fill()

test/mjsunit/harmony/array-fill.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
+
+assertEquals(1, Array.prototype.find.length);
+
+assertArrayEquals([0, 0, 0, 0, 0].fill(), [undefined, undefined, undefined, undefined, undefined]);
+assertArrayEquals([0, 0, 0, 0, 0].fill(8), [8, 8, 8, 8, 8]);

[Dmitry Lomov (no reviews), 2014/04/28 11:18:25]

Add test for empty array. 
Add test for negative start and no end.
Add test for start > length.

+assertArrayEquals([0, 0, 0, 0, 0].fill(8, 1), [0, 8, 8, 8, 8]);
+assertArrayEquals([0, 0, 0, 0, 0].fill(8, 1, 4), [0, 8, 8, 8, 0]);
+assertArrayEquals([0, 0, 0, 0, 0].fill(8, 1, -1), [0, 8, 8, 8, 0]);
+assertArrayEquals([0, 0, 0, 0, 0].fill(8, 1, 42), [0, 8, 8, 8, 8]);
+assertArrayEquals([0, 0, 0, 0, 0].fill(8, -3, 42), [0, 0, 8, 8, 8]);
+assertArrayEquals([0, 0, 0, 0, 0].fill(8, -3, 4), [0, 0, 8, 8, 0]);
+assertArrayEquals([0, 0, 0, 0, 0].fill(8, -2, -1), [0, 0, 0, 8, 0]);
+assertArrayEquals([0, 0, 0, 0, 0].fill(8, -1, -3), [0, 0, 0, 0, 0]);
+assertArrayEquals([0, 0, 0, 0, 0].fill(8, undefined, 4), [8, 8, 8, 8, 0]);
+assertArrayEquals([ ,  ,  ,  , 0].fill(8, 1, 3), [, 8, 8, , 0]);
+
+// If the range if empty, the array is not actually modified and
+// should not throw, even when applied to a frozen object.
+assertArrayEquals(Object.freeze([1, 2, 3]).fill(0, 0, 0), [1, 2, 3]);
+
+// Test exceptions
+assertThrows('Object.freeze([0]).fill()', TypeError);
+assertThrows('Array.prototype.fill.call(null)', TypeError);
+assertThrows('Array.prototype.fill.call(undefined)', TypeError);