bug#13521: `sort-lines' on the empty region

[Eli Zaretskii]

> From: Stefan Kangas <stefan@marxist.se>
> Date: Thu, 20 Aug 2020 18:18:34 -0700
> Cc: Xue Fuqiao <xfq.free@gmail.com>, Glenn Morris <rgm@gnu.org>,
>  13521@debbugs.gnu.org
> 
> > I personally prefer the "whole buffer", but whoever makes the change
> > gets to make the choice.
> 
> The attached patch makes 'sort-lines' sort the entire buffer when there
> is no region.

How frequently did you see a buffer in Emacs with no region in it?
IME, it takes about 2 commands since buffer creation to have a region
in it.  So I predict users to be tripped by this feature quite a lot:
they will think there's no region, invoke the command, and get some
arbitrary region sorted.  Requiring them to always provide the region
avoids this pitfall, since the user is forced to make sure the region
is where he or she wants it.  And marking the whole buffer is just 2
key-presses away.

So I think this change will annoy more than help.