Subject: bug#49774: 27.1; if diff commands finds no differences then do not pop up a window

From: Lars Ingebrigtsen <[email-masked]>
Date: Fri, 30 Jul 2021 12:03:29 +0200

ndame <[email-masked]> writes:

>> That would require it to wait until Diff has finished running before
>> showing the window. Currently 'M-x diff' works asynchronously, which has
>> its benefits.
>
> If exit status is zero then diff should restore  the previous window config
> automatically and show the message.

This is what `M-x man' does (when it turns out that the manual page
doesn't exist), and people really dislike that, too (the "flickering"
has been reported as a bug multiple times).

So I don't think we want to extend that user experience in Emacs.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no