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

[Lars Ingebrigtsen]

Often when discussing code changes, people will send an email saying
something like "this was fixed by <id>", but Emacs doesn't have a
convenient way to display that.

For that case, Emacs should have a command that prompts for an ID
(defaulting to the ID under point), and then (unless default-directory
is already in a vc-controlled directory), prompts for the directory to
look for that ID, and then display the commit.

Stefan M also commented:

> It's worse: if the commit is not in the current branch it won't be
> listed at all, and `C-x v L` doesn't let you show the log corresponding
> to another branch.
> 
> If `C-x v l` accepted a C-u to specify the "revision" for which to show
> the log, then it would solve both problems: you could get the log
> of other branches and you could see the commit message and the diff of
> a specific REVision with:
> 
> C-u C-x v l <REV> RET
> followed by hitting `D` on the first element to see the diff

This would be a separate change, because it can also be useful to see a
commit in context.


In GNU Emacs 27.0.50 (build 6, x86_64-pc-linux-gnu, GTK+ Version 3.24.5)
 of 2019-11-01 built on marnie
Repository revision: eda98211e31ed969823c1048b3cde635e08eebe5
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12004000
System Description: Debian GNU/Linux 10 (buster)


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