The fasteners.process_lock.InterProcessLock when used in a with block will wait indefinitely for the lock to be available. This can cause tests to hang indefinitely. Suggestion is to create the lock and manually acquire with a timeout and do a release.
Created attachment 419007 [details] Patch
Don and I discussed this on Slack. Long term, this may be correct, but the root of this problem on Windows may be the fact that we're using threads instead of processes. https://bugs.webkit.org/show_bug.cgi?id=217680 is going to fix that, so for now, we're going to skip the effected tests on Windows.
<rdar://problem/74110831>