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// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-proxy-object-internal-methods-and-internal-slots-isextensible
description: >
If "isExtensible" trap is null or undefined, [[IsExtensible]] call is
properly forwarded to [[ProxyTarget]] (which is also a Proxy object).
info: |
[[IsExtensible]] ( )
[...]
4. Let target be O.[[ProxyTarget]].
5. Let trap be ? GetMethod(handler, "isExtensible").
6. If trap is undefined, then
a. Return ? IsExtensible(target).
IsExtensible ( O )
1. Assert: Type(O) is Object.
2. Return ? O.[[IsExtensible]]().
features: [Proxy]
---*/
var regExp = /(?:)/g;
Object.preventExtensions(regExp);
var regExpTarget = new Proxy(regExp, {});
var regExpProxy = new Proxy(regExpTarget, {});
assert(!Object.isExtensible(regExpProxy));
reportCompare(0, 0);