Re: git describe number of commits different from git log count

[Aaron Schrab <aaron@schrab.com>]

At 12:17 +0100 05 Feb 2016, Jan Hudec <bulb@ucw.cz> wrote:
>I have a repository with following situation:
>
>    $ git describe next
>    v4.1-2196-g5a414d7
>    $ git describe next --match=v4.2
>    v4.2-4757-g5a414d7
>
>Since the tag with fewest commits since is selected, it appears logical.
>However, v4.2 is descendant of v4.1, so it does not make sense for it to have
>more commits since. And rev-list or log confirm that:
>
>    $ git rev-list v4.1..next | wc -l
>    2196
>    $ git rev-list v4.2..next | wc -l
>    1152
>
>The number of commits since v4.1 matches what the describe counted, but the
>number of commits since v4.2 does not.

I'm encountering what seems to be a similar issue. I'm working with the 
`build` branch of https://github.com/aschrab/mutt currently at 65b7094.  
Most of the commits in that repo come from a mercurial repository, but I 
don't think that is really effecting things (other than being related to 
the need to use the --tags option).

  $ git describe --tags
  mutt-1-7-1-rel-137-g65b7094

  $ git describe --tags --match=mutt-1-7-2-rel
  mutt-1-7-2-rel-6246-g65b7094

  $ git rev-list --count mutt-1-7-2-rel..HEAD
  126

  $ git rev-list --count mutt-1-7-1-rel..HEAD
  137

  $ git --version
  git version 2.10.2

The number of additional commits shown when I force the tag is 
completely insane! That's nearly every commit that is part of that 
branch:

  1036$ git rev-list --count HEAD
  6250

Both of the tags above should be reachable along the first-parent path.  
If I add the `--first-parent` option to the describe command it picks 
the expected tag and the number additional commits seems sane:

  $ git describe --tags --first-parent
  mutt-1-7-2-rel-14-g65b7094