Bug report

https://www.php.net/manual/en/function.mb-convert-encoding.php

Function returns false on error. I checked phpstan-src, and it does have the correct return type there (string|array|false), but in reality, phpstan reports identical.alwaysFalse.

This particular case can happen when there are certain unicode characters in the input, so we want to check if it is false specifically.

Code snippet that reproduces the problem

https://phpstan.org/r/e833d30c-5c4c-448c-9f1e-98d611a3e691

Expected output

No error.

Did PHPStan help you today? Did it make you happy in any way?

No response