The Tor Browser: js/src/jit-test/tests/proxy/testDirectProxyValidateProperty4.js@b8a032363ba2

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

     1 load(libdir + "asserts.js");

     3 /*

     4  * Throw a TypeError if both the current descriptor and the descriptor returned

     5  * by the trap are data descriptors, the current descriptor is non-configurable

     6  * and non-writable, and the descriptor returned by the trap is writable.

     7  */

     8 var target = {};

     9 Object.defineProperty(target, 'foo', {

    10     value: 'bar',

    11     writable: false,

    12     configurable: false

    13 });

    14 assertThrowsInstanceOf(function () {

    15     Object.getOwnPropertyDescriptor(new Proxy(target, {

    16         getOwnPropertyDescriptor: function (target, name) {

    17             return {

    18                 value: 'bar',

    19                 writable: true,

    20                 configurable: false

    21             };

    22         }

    23     }), 'foo');

    24 }, TypeError);

The Tor Browser / file revision