/// Copyright (c) 2012 Ecma International. All rights reserved. /// Ecma International makes this code available under the terms and conditions set /// forth on http://hg.ecmascript.org/tests/test262/raw-file/tip/LICENSE (the /// "Use Terms"). Any redistribution of this code must retain the above /// copyright and this notice and otherwise comply with the Use Terms. /** * @path ch15/15.4/15.4.4/15.4.4.15/15.4.4.15-8-a-15.js * @description Array.prototype.lastIndexOf - deleting own property with prototype property causes prototype index property to be visited on an Array-like object */ function testcase() { var arr = { 0: 0, 1: 111, 2: 2, length: 10 }; Object.defineProperty(arr, "6", { get: function () { delete arr[1]; return 0; }, configurable: true }); try { Object.prototype[1] = 1; return 1 === Array.prototype.lastIndexOf.call(arr, 1); } finally { delete Object.prototype[1]; } } runTestCase(testcase);