Re: "git describe --debug" does not show the latest tag for "groff"

On Wed, Oct 27 2021, Bjarni Ingi Gislason wrote:

What did you do before the bug happened? (Steps to reproduce your issue)

  I do not know, it could have happened anytime after the latest tag
was committed (11th Nov. 2020).

What did you expect to happen? (Expected behavior)

  Seeing the latest tag "1.23.0.rc1" in the version string of "groff"
(and in the output of "git describe --debug")

What happened instead? (Actual behavior)

  "groff --version" shows for example "1.22.4.3317-8f8c8-dirty"

  "git describe --debug" shows:

describe HEAD
No exact match on refs or tags, searching to describe
finished search at 2ac1f9ba5578cad27dc547d5be3c91753db436ea
 annotated       3318 1.22.4
 annotated       3319 1.22.4.rc5
 annotated       3352 1.22.4.rc4
 annotated       3464 1.22.4.rc3
 annotated       3485 1.23.0.rc1
 annotated       3572 1.22.4.rc2
 annotated       3619 1.22.3.rc1
traversed 3833 commits
1.22.4-3318-g3a1e750d

What's different between what you expected and what actually happened?

  The latest tag is not shown for the groff version.

Anything else you want to add:


  The latest tag in "git log" is 1.23.0.rc1 in my branch.
  It is 1.23.0.rc1 in branch master.

  Search for "tag:" in "git log" in my branch shows:

commit c05b538c504106d55b81caa6400ea80797f03775 (tag: 1.23.0.rc1)
Author: Bertrand Garrigues <...>
Date:   Wed Nov 11 01:58:55 2020 +0100

  "git show-ref 1.23.0.rc1" in my branch shows:

faa3dff8d011e61721e763c71b6ccbf20a4675bc refs/tags/1.23.0.rc1

####

  "git-version-gen" (gnulib) does not get the latest tag.

  The call in configure.am is:

AC_INIT([GNU Troff],[m4_esyscmd(build-aux/git-version-gen --prefix ""
.tarball-version)],[http://savannah.gnu.org/bugs/?group=g$

  The files ".git/packed-refs" and ".git/info/refs" are the same in both
branches.

#####

[System Info]
git version 2.33.0 (Debian/testing Version: 1:2.33.0-1)
cpu: x86_64
no commit associated with this build
sizeof-long: 8
sizeof-size_t: 8
shell-path: /bin/sh
uname: Linux 5.14.9-2 #1 SMP Sun Oct 10 01:53:44 UTC 2021 x86_64
compiler info: gnuc: 10.2
libc info: glibc: 2.32
$SHELL (typically, interactive shell): /bin/bash

Daginn.

The "git describe" command won't just return the latest tag name, but if
you're not on such an exact tag name find the "closest", and then add a
suffix indicating the distance and HEAD commit.

Reading between the lines I think you know that, but you're suprised
that it's finding 1.22.4 instead of 1.23.0.rc1, which newer.

I tried to reproduce this and cloned
https://git.savannah.gnu.org/git/groff.git; If you run e.g. this
command:
    
    $ for c in $(git log --oneline 1.22.4..1.23.0.rc1 | awk '{print $1}'); do git describe $c; done
    1.23.0.rc1
    1.22.4-765-g10cd0b66
    1.22.4-764-ge3b774ad
    1.22.4-763-gfb52df3b
    1.22.4-762-g0f42ca27
    1.22.4-761-gdf73fc2b
    1.22.4-760-g3afeb883
    1.22.4-759-gcb1a9dc5
    [...]

You'll see us describing all commits between 1.22.4..1.23.0-rc0, ending with:
    
    [...]
    1.22.4-7-g72b4440e
    1.22.4-6-g81908bc0
    1.22.4-5-g9da68905
    1.22.4-4-g2212cba0
    1.22.4-3-ga3068bfd
    1.22.4-2-g607236cc
    1.22.4-1-gde9f9bfd

But as your tag "1.22.4.3317-8f8c8-dirty" shows we're at a distance of
3317 from 1.22.4. Are you able to share whatever your 8f8c8 is
somewhere? I wonder if you're on some commit based off an older version.

Aside from what ref "describe" picked it's weird that a new version of
git would choose to show a 5-character hex abbreviation of the commit,
the minimum we show these days is 7, unless you have something setting
e.g. this in config:

    core.abbrev=5

Or maybe that AC_INIT() macro does that somehow...