mirror of https://github.com/tc39/test262.git
34 lines
1.1 KiB
JavaScript
34 lines
1.1 KiB
JavaScript
// Copyright (C) 2017 Claude Pache. All rights reserved.
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// This code is governed by the BSD license found in the LICENSE file.
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/*---
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esid: sec-invariants-of-the-essential-internal-methods
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description: >
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Value of non-writable, non-configurable data property must not change
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("arguments" property of a non-strict function)
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info: |
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[[GetOwnProperty]] (P)
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[...]
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- If a property P is described as a data property with Desc.[[Value]] equal
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to v and Desc.[[Writable]] and Desc.[[Configurable]] are both false, then
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the SameValue must be returned for the Desc.[[Value]] attribute of the
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property on all future calls to [[GetOwnProperty]] ( P ).
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[...]
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(This invariant was violated for the specific property under test by a number
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of implementations as of January 2017.)
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---*/
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function f() {
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return Reflect.getOwnPropertyDescriptor(f, 'arguments');
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}
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Reflect.defineProperty(f, 'arguments', {
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writable: false,
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configurable: false
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});
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var desc = Reflect.getOwnPropertyDescriptor(f, 'arguments');
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if (desc && desc.configurable === false && desc.writable === false) {
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var desc2 = f();
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assert.sameValue(desc.value, desc2.value);
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}
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