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// Copyright (c) 2012 Ecma International. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
info: |
Step 4 of defineProperty calls the [[DefineOwnProperty]] internal method
of O to define the property. Step 6 of [[DefineOwnProperty]] returns if
every field of desc also occurs in current and every field in desc has
the same value as current.
es5id: 15.2.3.6-4-5
description: >
Object.defineProperty is no-op if current and desc are the same
data desc
---*/
function sameDataDescriptorValues(d1, d2) {
return (d1.value === d2.value &&
d1.enumerable === d2.enumerable &&
d1.writable === d2.writable &&
d1.configurable === d2.configurable);
}
var o = {};
// create a data valued property with the following attributes:
// value: 101, enumerable: true, writable: true, configurable: true
o["foo"] = 101;
// query for, and save, the desc. A subsequent call to defineProperty
// with the same desc should not disturb the property definition.
var d1 = Object.getOwnPropertyDescriptor(o, "foo");
// now, redefine the property with the same descriptor
// the property defintion should not get disturbed.
var desc = {
value: 101,
enumerable: true,
writable: true,
configurable: true
};
Object.defineProperty(o, "foo", desc);
var d2 = Object.getOwnPropertyDescriptor(o, "foo");
assert.sameValue(sameDataDescriptorValues(d1, d2), true, 'sameDataDescriptorValues(d1, d2)');
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