Actually for PHP 7.1+ it's not the same...

https://3v4l.org/ZH8Z5 vs https://3v4l.org/UgH0S

Changing this in just one file is a no go. We should first decide to change a decision we made some years ago to never use return null and then make the change everywhere. I think it's not worth it. I prefer to postpone the change to when we week decide to use type hints for return values.

According to Coding Standard both methods are feasible:

Use return null; when a function explicitly returns null values and use return; when the function returns void values;

So it should depend of @return ? phpdoc?

Same pov as @fabpot, we may close this PR to me :)

Same for me.

I suppose you need to open an issue about it and add it to the 4.0 milestone if you close this one, right? :)

@bocharsky-bw IIRC we "somewhere" have an open issue.

EDIT: see #17201