test/built-ins/Proxy/getOwnPropertyDescriptor/result-is-undefined-target-is-not-extensible.js


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32

// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
es6id: 9.5.5
description: >
    Throws a TypeError exception if trap result is undefined and target is not
    extensible
info: |
    [[GetOwnProperty]] (P)

    ...
    14. If trapResultObj is undefined, then
        ...
        e. If ToBoolean(extensibleTarget) is false, throw a TypeError exception.
    ...
---*/

var target = {
    foo: 1
};

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

Object.preventExtensions(target);

assert.throws(TypeError, function() {
    Object.getOwnPropertyDescriptor(p, "foo");
});