test262/test/built-ins/Proxy/defineProperty/trap-is-null-target-is-prox...

58 lines
1.4 KiB
JavaScript

// 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-defineownproperty-p-desc
description: >
If "defineProperty" trap is null or undefined, [[DefineOwnProperty]] call
is properly forwarded to [[ProxyTarget]] (which is also a Proxy object).
info: |
[[DefineOwnProperty]] (P, Desc)
[...]
5. Let target be O.[[ProxyTarget]].
6. Let trap be ? GetMethod(handler, "defineProperty").
7. If trap is undefined, then
a. Return ? target.[[DefineOwnProperty]](P, Desc).
features: [Proxy, Reflect]
includes: [propertyHelper.js]
---*/
var plainObject = Object.create(null);
Object.defineProperty(plainObject, "foo", {
configurable: false,
});
var plainObjectTarget = new Proxy(plainObject, {});
var plainObjectProxy = new Proxy(plainObjectTarget, {
defineProperty: null,
});
assert.throws(TypeError, function() {
Object.defineProperty(plainObjectProxy, "foo", {
configurable: true,
});
});
Object.defineProperty(plainObjectProxy, "bar", {
get: function() {
return 2;
},
});
assert.sameValue(plainObject.bar, 2);
var regExp = /(?:)/g;
var regExpTarget = new Proxy(regExp, {});
var regExpProxy = new Proxy(regExpTarget, {
defineProperty: null,
});
assert(
Reflect.defineProperty(regExpProxy, "lastIndex", {
writable: false,
})
);
verifyNotWritable(regExp, "lastIndex");