bug#71499: [PATCH] Make whitespace.el cleanup add missing final newline

[Eli Zaretskii]

> Date: Tue, 11 Jun 2024 20:16:03 +0200
> From: Björn Lindström <bkhl@elektrubadur.se>
> 
> attaching patch to make the whitespace-cleanup and whitespace-cleanup-region 
> functions add a final newline to a file if whitespace-style contains 
> `missing-newline-at-eof
> 
> I'm aware this somewhat replicates what setting `require-final-newline would 
> do, but I think since whitespace.el with this configuration highlights this 
> as an error, it should also clean it up when asked.

This is an incompatible change of behavior on behalf of
whitespace-cleanup, so I don't think we can accept it as in this patch
(or the next one you sent).  Se we'd need some new user option, by
default off, to turn on this new feature.  Or maybe a new action for
whitespace-action?

Thanks.