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// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
es6id: 26.1.12
description: >
Prevent extentions on target.
info: |
26.1.12 Reflect.preventExtensions ( target )
...
2. Return target.[[PreventExtensions]]().
9.1.4 [[PreventExtensions]] ( )
1. Set the value of the [[Extensible]] internal slot of O to false.
...
---*/
var o = {};
Reflect.preventExtensions(o);
assert.sameValue(Object.isExtensible(o), false, 'object is not extensible');
assert.throws(TypeError, function() {
Object.defineProperty(o, 'y', {});
});
assert.throws(TypeError, function() {
Object.setPrototypeOf(o, Array.prototype);
});
Reflect.preventExtensions(o);
assert.sameValue(
Object.isExtensible(o), false,
'object is still not extensible on exhausted calls'
);
|
