"messageParent" can only be used inside a worker

[calebeby]

I keep running into this error so I'm opening an issue in case anyone else runs into it

This is an issue from Jest: jestjs/jest#10577

It has been fixed in this PR: jestjs/jest#10981 but the fix isn't published on npm yet.

For now, if you restart jest, then the error goes away (at least for a while)

[calebeby]

AFAICT this workaround fixes it: 1482257

The issue was intermittent with jest-circus and consistently reproducible with the jest-jasmine2 runner. With that commit, I no longer reproduce the issue with either runner.