While you are on this matter, could you change the else if part to an assertion? The locals should either be a FrameLocalsProxy or a mapping at least. Just remove the else if case and change that to an assertion. Then you can always return locals at the end of the function.

Otherwise, logically, you need to handle the else case which should not ever exist.

Since #115153 was not backported, I also don't backport.

Thanks everyone! 👍

This piece of code has only been in main for like 2 days so there's no need to backport :)