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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-preventextensions
description: >
If "preventExtensions" trap is null or undefined, [[PreventExtensions]] call
is properly forwarded to [[ProxyTarget]] (which is also a Proxy object).
info: |
[[PreventExtensions]] ( )
[...]
4. Let target be O.[[ProxyTarget]].
5. Let trap be ? GetMethod(handler, "preventExtensions").
6. If trap is undefined, then
a. Return ? target.[[PreventExtensions]]().
features: [Proxy]
---*/
var target = new Proxy({}, {
preventExtensions: function(_target) {
return false;
},
});
var proxy = new Proxy(target, {});
assert.throws(TypeError, function() {
Object.preventExtensions(proxy);
});
reportCompare(0, 0);