Steps to reproduce
At wpt commit 7005b60351c6bd8dc6be07e2a290f5df3909f134, http://w3c-test.org/html/dom/interfaces.html does not produce reliable results.
The subtest that sometimes fails and sometimes passes is 'Document interface: document.implementation.createDocument(null, "", null) must inherit property “all” with the proper type (75)'
The test itself is probably invalid, but when it fails it’s here:
It seems like the "property = obj[member.name]" bit in “IdlInterface.prototype.test_interface_of” doesn’t always result in the same value.
An attempt to minify the test in https://github.com/w3c/web-platform-tests/pull/5963 made the problem go away.
Comments and activity
I’ve been unable to reproduce this in Edge 15 at all; in Edge 14 it’s completely stable with the devtools open which suggests my hypothesis about it being a JIT issue is accurate.
I’m fairly certain
property = obj[member.name]is consistent; it’s when it then calls a function, binding that
valueas an argument and then doing
typeof valueit’s inconsistent, sometimes returning “undefined” and sometimes "object". Given the magic around HTMLAllCollection, this isn’t the most surprising of bugs. :)
OK, no, finally got it to repro. After many, many, many reloads. Can’t really tell if having devtools open makes any difference because it’s so rare.
- Microsoft Edge Team
Changed Assigned To to “Brian T.”
Changed Assigned To from “Brian T.” to “Paul L.”
Changed Status to “Confirmed”