/// 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 ch15/15.4/15.4.4/15.4.4.15/15.4.4.15-3-23.js * @description Array.prototype.lastIndexOf uses inherited valueOf method when 'length' is an object with an own toString and an inherited valueOf methods */ function testcase() { var toStringAccessed = false; var valueOfAccessed = false; var proto = { valueOf: function () { valueOfAccessed = true; return 2; } }; var Con = function () {}; Con.prototype = proto; var child = new Con(); child.toString = function () { toStringAccessed = true; return 2; }; var obj = { 1: child, length: child }; return Array.prototype.lastIndexOf.call(obj, child) === 1 && valueOfAccessed && !toStringAccessed; } runTestCase(testcase);