| // Copyright (c) 2012 Ecma International. All rights reserved. |
| // This code is governed by the BSD license found in the LICENSE file. |
| |
| /*--- |
| esid: sec-array.prototype.foreach |
| description: > |
| Array.prototype.forEach - k values are accessed during each |
| iteration and not prior to starting the loop on an Array |
| ---*/ |
| |
| var result = true; |
| var kIndex = []; |
| |
| //By below way, we could verify that k would be setted as 0, 1, ..., length - 1 in order, and each value will be setted one time. |
| function callbackfn(val, idx, obj) { |
| //Each position should be visited one time, which means k is accessed one time during iterations. |
| if (typeof kIndex[idx] === "undefined") { |
| //when current position is visited, its previous index should has been visited. |
| if (idx !== 0 && typeof kIndex[idx - 1] === "undefined") { |
| result = false; |
| } |
| kIndex[idx] = 1; |
| } else { |
| result = false; |
| } |
| } |
| |
| [11, 12, 13, 14].forEach(callbackfn, undefined); |
| |
| assert(result, 'result !== true'); |
