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

From: ndame <[email-masked]>
Date: Thu, 29 Jul 2021 16:59:18 +0000

When diff exit code is zero and there are no differences then a window pops up showing output like "Diff finished (no differences)" and the user has to dismiss this useless window.

If there are no differences then emacs should just show this in a message instead of popping up a window with not useful content.