bug#67462: 30.0.50; prog-fill-reindent-defun does not respect buffer-local fill-paragraph-function

[Jens Schmidt]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Jens Schmidt <jschmidt4gnu@vodafonemail.de>
>> Cc: 67462@debbugs.gnu.org,  dmitry@gutov.dev
>> Date: Wed, 29 Nov 2023 22:28:49 +0100
>>
>> No, indent-region does a good job and there is nothing to fix here.  But
>> starting with Emacs 30 it does that job (also) on M-q, where previously
>> other functionality may have been bound.
>>
>> To see the difference, please try executing in Emacs 29 vs master on
>> Emacs's own, configured Makefile:
>>
>>   ./src/emacs -Q Makefile --eval '(search-forward "SUBDIR_MAKEFILES_IN")'
>>   M-q
>
> So the problem is that the new code does its job, just with different
> results than the mode-specific fill-paragraph-function did in Emacs 29
> and before?

Yes.

> If so, perhaps we should offer a user option to let users choose which
> method to use, because some might prefer the new behavior?

I'd be fine with that, and also with making the new behavior the
default.  A reference to that user option would also nicely complete the
NEWS entry, which IMO currently is a bit weak in mentioning the possible
consequences of the new feature.

Dmitry, what do you think?