Fix array_column() with explicit null $index_key

[herndlm]

Closes phpstan/phpstan#12945

[herndlm]

hey @staabm, I only saw your refactor in #3785 now because of conflicts :) I think the $indexType should not be nullable to avoid confusion / inconsistency with null vs NullType.

I think your follow-up for the rules does not exist yet, does it? Would it work with a non-nullable indexType too? I did adapt the new helper here with the rebase to keep the fix for the linked issue simple.

@ondrejmirtes I avoid pinging you, but looks like this small fix is a blocker or has conflict potential for that new rule

[staabm]

thanks for the ping

I think the $indexType should not be nullable to avoid confusion / inconsistency with null vs NullType.

IIRC its fine, as the rule - as I had it implemted previously in https://github.com/phpstan/phpstan-src/pull/3706/files - does not rely on the nullability of the parameter.

I will have a closer look when re-submitting the new rule

[herndlm]

jfyi, this is an easy one I think and done already for a while

[ondrejmirtes]

Thank you!