JSTests/test262/test/built-ins/Proxy/preventExtensions/return-true-target-is-not-extensible.js

// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
es6id: 9.5.4
description: >
    Return boolean trap result if its true and target is not extensible.
features: [Proxy, Reflect]
---*/

var target = {};
var p = new Proxy(target, {
  preventExtensions: function(t) {
    return 1;
  }
});

Object.preventExtensions(target);

assert(Reflect.preventExtensions(p));