15.2.3.6-4-14.js (1248B)
1 // Copyright (c) 2012 Ecma International. All rights reserved. 2 // This code is governed by the BSD license found in the LICENSE file. 3 4 /*--- 5 info: | 6 Step 4 of defineProperty calls the [[DefineOwnProperty]] internal method 7 of O to define the property. For configurable properties, step 9b of 8 [[DefineOwnProperty]] permits changing the kind of a property. 9 es5id: 15.2.3.6-4-14 10 description: > 11 Object.defineProperty permits changing data property to accessor 12 property for configurable properties 13 ---*/ 14 15 var o = {}; 16 17 // create a data property. In this case, 18 // [[Enumerable]] and [[Configurable]] are true 19 o["foo"] = 101; 20 21 // changing "foo" to be an accessor should succeed, since [[Configurable]] 22 // on the original property will be true. Existing values of [[Configurable]] 23 // and [[Enumerable]] need to be preserved and the rest need to be set to 24 // their default values 25 26 // dummy getter 27 var getter = function() { 28 return 1; 29 } 30 var d1 = { 31 get: getter 32 }; 33 Object.defineProperty(o, "foo", d1); 34 35 var d2 = Object.getOwnPropertyDescriptor(o, "foo"); 36 37 assert.sameValue(d2.get, getter, 'd2.get'); 38 assert.sameValue(d2.enumerable, true, 'd2.enumerable'); 39 assert.sameValue(d2.configurable, true, 'd2.configurable'); 40 41 reportCompare(0, 0);