Bug report

if a function_exists call is used outside of a callback, it does not keep knowledge of that function existing inside of the callback.

I know this is some more 'special' code that may not happen in much projects, but i ran into this today 😅

Code snippet that reproduces the problem

https://phpstan.org/r/07fbfdd0-9f91-46bf-8a72-38aed2d5218f

Expected output

I expected no issues here