tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

trap-is-null-target-is-proxy.js (1561B)

      1 // Copyright (C) 2020 Alexey Shvayka. All rights reserved.
      2 // This code is governed by the BSD license found in the LICENSE file.
      3 
      4 /*---
      5 esid: sec-proxy-object-internal-methods-and-internal-slots-getownproperty-p
      6 description: >
      7  If "getOwnPropertyDescriptor" trap is null or undefined, [[GetOwnProperty]]
      8  call is properly forwarded to [[ProxyTarget]] (which is also a Proxy object).
      9 info: |
     10  [[GetOwnProperty]] ( P )
     11 
     12  [...]
     13  5. Let target be O.[[ProxyTarget]].
     14  6. Let trap be ? GetMethod(handler, "getOwnPropertyDescriptor").
     15  7. If trap is undefined, then
     16    a. Return ? target.[[GetOwnProperty]](P).
     17 includes: [propertyHelper.js]
     18 features: [Proxy]
     19 ---*/
     20 
     21 var plainObjectTarget = new Proxy({foo: 1}, {});
     22 var plainObjectProxy = new Proxy(plainObjectTarget, {
     23  getOwnPropertyDescriptor: null,
     24 });
     25 
     26 verifyProperty(plainObjectProxy, "bar", undefined);
     27 verifyProperty(plainObjectProxy, "foo", {
     28  value: 1,
     29  writable: true,
     30  enumerable: true,
     31  configurable: true,
     32 });
     33 
     34 
     35 var fooDescriptor = {
     36  get: function() {},
     37  set: function(_value) {},
     38  enumerable: false,
     39  configurable: true,
     40 };
     41 
     42 var target = new Proxy({}, {
     43  getOwnPropertyDescriptor: function(_target, key) {
     44    if (key === "foo") {
     45      return fooDescriptor;
     46    }
     47  },
     48  deleteProperty: function(_target, key) {
     49    if (key === "foo") {
     50      fooDescriptor = undefined;
     51    }
     52 
     53    return true;
     54  },
     55 });
     56 
     57 var proxy = new Proxy(target, {
     58  getOwnPropertyDescriptor: null,
     59 });
     60 
     61 verifyProperty(proxy, "bar", undefined);
     62 verifyProperty(proxy, "foo", fooDescriptor);
     63 
     64 reportCompare(0, 0);