Add failing test for #17213

[samcooke98]

I've tried to add a failing test for the issue described here.
#17314

If you run it locally, and change isMemo to be false, the test will pass. The test will also pass if you change the line to
const MemodSubbed = isMemo ? React.memo(Subbed, () => true) : Subbed;

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Below are my half-hearted attempts to look into this bug.

It looks like when the compare function is defined it makes React call createFiberFromTypeAndProps. However, if the compare function is not defined, it means React goes down the codepath below;

https://github.com/facebook/react/blob/master/packages/react-reconciler/src/ReactFiberBeginWork.js#L380-L403

In other words, the bug is likely caused somewhere in updateSimpleMemoComponent

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[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contribution.

[stale]

Closing this pull request after a prolonged period of inactivity. If this issue is still present in the latest release, please ask for this pull request to be reopened. Thank you!

[gaearon]

Thank you for the test! Took us a while to get to this. Sorry this got autoclosed.
We think #18091 should fix it.

[samcooke98]

Thanks @gaearon ! Andrew told me as well: #17314 (comment) :D