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vm: accessor properties get converted to data properties inside the vm #2734
Description
Example:
'use strict';
const vm = require('vm');
const x = {};
Object.defineProperty(x, 'prop', {
get() { return 'foo'; }
});
const o = vm.createContext(x);
const code = 'Object.getOwnPropertyDescriptor(this, "prop")';
const res = vm.runInContext(code, o, 'test');
console.log(res);gives
$ iojs test.js
Object {
value: 'foo',
writable: true,
enumerable: false,
configurable: false }
In 659dadd I fixed it to return the correct data descriptor. But it appears the accessor descriptor is just broken.
As far as I can tell this is a shortcoming of the V8 API. The named properties handler and the GlobalPropertyQueryCallback always returns data descriptors. This is probably because that is all that is required by Web IDL for the browser use case, where the named property handler is meant to be used for things like window.idOrName or window.forms.foo, which are always data descriptors.
I think Chrome also has this problem. Even for non-named properties, things like window.top are data descriptors. I'm asking related questions on blink-dev.
Original discovery: jsdom/jsdom#1208, where this is affecting Facebook's use in jest.
/cc @nodejs/v8
Activity
nicolashenry commentedon Sep 8, 2015
I have an issue that may be related :
gives
test: add batch of known issue tests
test: add batch of known issue tests
test: add batch of known issue tests
jasnell commentedon Apr 13, 2016
@domenic @ofrobots ... I see this is still occurring v4.9 in master. Any updates on this?
11 remaining items
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src: use new V8 API in vm module