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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 7b of [[DefineOwnProperty]] rejects if
current.[[Enumerable]] and desc.[[Enumerable]] are the boolean negations
of each other.
es5id: 15.2.3.6-4-9
description: >
Object.defineProperty throws TypeError when changing
[[Enumerable]] from true to false on non-configurable data
properties
---*/
var o = {};
// create a data valued property with [[Enumerable]] explicitly set to true;
// all other attributes default to false.
var d1 = { value: 101, enumerable: true, configurable: false };
Object.defineProperty(o, "foo", d1);
// now, setting enumerable to false should fail, since [[Configurable]]
// on the original property will be false.
var desc = { value: 101, enumerable: false };
assert.throws(TypeError, function() {
Object.defineProperty(o, "foo", desc);
});
// the property should remain unchanged.
var d2 = Object.getOwnPropertyDescriptor(o, "foo");
assert.sameValue(d2.value, 101, 'd2.value');
assert.sameValue(d2.enumerable, true, 'd2.enumerable');
assert.sameValue(d2.configurable, false, 'd2.configurable');
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