bug#38044: 27.0.50; There should be an easier way to look at a specific vc commit

[Eli Zaretskii]

> Cc: larsi@gnus.org, stephen.berman@gmx.net, 38044@debbugs.gnu.org,
>  juri@linkov.net
> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Fri, 22 Nov 2019 23:43:08 +0200
> 
> On 22.11.2019 23:03, Eli Zaretskii wrote:
> > I'd prefer to use "log -p" in the backend ("log --diff" for svn),
> > because that yields a single command and will work for all the
> > backends except RCS and CVS.
> 
> Would it?
> 
> For Git, we need 'git log -p -n 1', for Hg, 'hg log -p -l 1'. So it's 
> hard to do the default implementation.

I didn't mean to say that we should have a default implementation, I
meant to have an implementation in each backend.  So small differences
in the commands to be issued are not an issue.

> If you still mean to update the print-log action (which will mean 
> updating all backends), I'm okay with that essentially, except we'd 
> likely document the extra argument as "also print diffs for each 
> revision". It would be weird for it to mean "show diffs INSTEAD of the 
> revision log" only in CVS and RCS. But if someone wants to implement it 
> that way (with ample commentary), I won't stop them.

I'd prefer it that way, yes.

> I do think this should be better invoked via a new user-visible command, 
> though.

I don't object to having a separate command as well, but not instead
of "C-x v L".