/// 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. /** * Step 4 of defineProperty calls the [[DefineOwnProperty]] internal method * of O to define the property. Step 7b of [[DefineOwnProperty]] rejects if * current.[[Enumerable]] and desc.[[Enumerable]] are the boolean negations * of each other. * * @path ch15/15.2/15.2.3/15.2.3.6/15.2.3.6-4-11.js * @description Object.defineProperty throws TypeError when changing [[Enumerable]] from true to false on non-configurable accessor properties */ function testcase() { var o = {}; // create an accessor property; all other attributes default to false. // dummy getter var getter = function () { return 1; } var d1 = { get: getter, enumerable: true, configurable: false }; Object.defineProperty(o, "foo", d1); // now, setting enumerable to true should fail, since [[Configurable]] // on the original property will be false. var desc = { get: getter, enumerable: false }; try { Object.defineProperty(o, "foo", desc); } catch (e) { if (e instanceof TypeError) { // the property should remain unchanged. var d2 = Object.getOwnPropertyDescriptor(o, "foo"); if (d2.get === getter && d2.enumerable === true && d2.configurable === false) { return true; } } } } runTestCase(testcase);