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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. For non-configurable properties, step 9a of
[[DefineOwnProperty]] rejects changing the kind of a property.
es5id: 15.2.3.6-4-12
description: >
Object.defineProperty throws TypeError when changing
non-configurable data properties to accessor properties
---*/
var o = {};
// create a data valued property; all other attributes default to false.
var d1 = {
value: 101,
configurable: false
};
Object.defineProperty(o, "foo", d1);
// changing "foo" to be an accessor should fail, since [[Configurable]]
// on the original property will be false.
// dummy getter
var getter = function() {
return 1;
}
var desc = {
get: getter
};
assert.throws(TypeError, function() {
Object.defineProperty(o, "foo", desc);
});
// the property should remain a data valued property.
var d2 = Object.getOwnPropertyDescriptor(o, "foo");
assert.sameValue(d2.value, 101, 'd2.value');
assert.sameValue(d2.writable, false, 'd2.writable');
assert.sameValue(d2.enumerable, false, 'd2.enumerable');
assert.sameValue(d2.configurable, false, 'd2.configurable');
reportCompare(0, 0);
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