setuptools_scm silently reports garbage version with partial Git clone

[paugier]

Readthedocs clones with

git clone --no-single-branch --depth 50 https://github.com/snek5000/snek5000.git
cd snek5000
git checkout --force origin/main
git clean -d -f -f

With such clone,

$ git --git-dir .git describe --dirty --tags --long
fatal: No tags can describe '2a7b9f0b372163f19d0af2dc1cb6752528310530'.
Try --always, or create some tags.

In contrast, git tag gives the right list of tags. Anyway, setuptools_scm bases its analysis on git describe so it gives a wrong version (something like 0.1.dev173+g2a7b9f0).

To get the right version, I need to run:

$ git pull --unshallow
remote: Enumerating objects: 298, done.
remote: Counting objects: 100% (267/267), done.
remote: Compressing objects: 100% (84/84), done.
remote: Total 169 (delta 102), reused 138 (delta 78), pack-reused 0
Receiving objects: 100% (169/169), 23.59 KiB | 23.59 MiB/s, done.
Resolving deltas: 100% (102/102), completed with 22 local objects.
Already up to date.

$ git --git-dir .git describe --dirty --tags --long
0.8.0rc0-285-g2a7b9f0

I don't know what setuptools_scm could do about this case, but it is annoying. Maybe at least a warning?

CC @ashwinvis

[RonnyPfannschmidt]

there are some warnigns on shallw branches by default, its possible they gethidden

can you show the output of
SETUPTOOLS_SCM_DEBUG=1 python -m setuptools_scm

[RonnyPfannschmidt]

we might want to involve readthedocs in this as well as its not clear to me off hand how to fix it for them

[ashwinvis]

@paugier I am not sure what you mean. The final successful rtd build reported the correct version number

snek5000-0.8.0rc1.dev254+g7597f21

And there was no unshallow git operation.

https://readthedocs.org/projects/snek5000/builds/18787743/

https://readthedocs.org/api/v2/build/18787743.txt

[paugier]

@ashwinvis I think this is because of the --depth 50. I guess there are more than 50 commits behind the last tag. So before, Git managed to give the right tag. It still works fine with --depth 100.

[paugier]

The output of SETUPTOOLS_SCM_DEBUG=1 python -m setuptools_scm:

abs root {'root': '.', 'relative_to': '/tmp/snek5000/pyproject.toml'}
file /tmp/snek5000/pyproject.toml
root '/tmp/snek5000'
relative_to '/tmp/snek5000/pyproject.toml'
dist name: snek5000
version_from_ep setuptools_scm.parse_scm /tmp/snek5000
looking for ep setuptools_scm.parse_scm /tmp/snek5000
found ep EntryPoint(name='.git', value='setuptools_scm.git:parse', group='setuptools_scm.parse_scm') in /tmp/snek5000
----
cmd:
     git --git-dir /tmp/snek5000/.git rev-parse --show-prefix
 in: /tmp/snek5000
out:
 

real root /tmp/snek5000
/home/users/augier3pi/Dev/setuptools_scm/src/setuptools_scm/git.py:135: UserWarning: "/tmp/snek5000" is shallow and may cause errors
  warnings.warn(f'"{wd.path}" is shallow and may cause errors')
----
cmd:
     git --git-dir /tmp/snek5000/.git describe --dirty --tags --long --match "*[0-9]*"
 in: /tmp/snek5000
err:
     fatal: No tags can describe 'b1a8932c6ef7037d7ff70c2f8b76f0e0397c51c3'.
    Try --always, or create some tags.

ret: 128
----
cmd:
     git --git-dir /tmp/snek5000/.git rev-parse --verify --quiet HEAD
 in: /tmp/snek5000
out:
     b1a8932c6ef7037d7ff70c2f8b76f0e0397c51c3

----
cmd:
     git --git-dir /tmp/snek5000/.git rev-list HEAD
 in: /tmp/snek5000
out:
     b1a8932c6ef7037d7ff70c2f8b76f0e0397c51c3
    8837551db1944f3ba8860fb7cf555824ba1daaa9
    34c67672246635bac54204a800983674e7979071
    e511c0a2a57c30e8e3f2c9d7190f7ccd352bf7dc
    e70edf64dd3dea705383d9415061c21cb599b2ab
[...]
    d187fc5948d3b32a74eb672596e651f5f6344dc6
    e26856d9a68f10861e8e6ab53c69f40367c43d61
    f630c83ea38e7e5316fe7024df96aebb778692c1
    368d1326786720e053447bfca6f28b156ac7dcb7
    7676a79de5394186431c9e628798fd4813a5a1c2

----
cmd:
     git --git-dir /tmp/snek5000/.git status --porcelain --untracked-files=no
 in: /tmp/snek5000
----
cmd:
     git --git-dir /tmp/snek5000/.git rev-parse --abbrev-ref HEAD
 in: /tmp/snek5000
out:
     HEAD

----
cmd:
     git --git-dir /tmp/snek5000/.git -c log.showSignature=false log -n 1 HEAD --format=%cI
 in: /tmp/snek5000
out:
     2022-12-02T12:44:51+01:00

tag 0.0
tag '0.0' parsed to {'version': '0.0', 'prefix': '', 'suffix': ''}
version pre parse 0.0
version <Version('0.0')>
version 0.0 -> 0.0
EntryPoint(name='.git', value='setuptools_scm.git:parse', group='setuptools_scm.parse_scm') <ScmVersion 0.0 dist=161 node=gb1a8932 dirty=False branch=HEAD>
scm version <ScmVersion 0.0 dist=161 node=gb1a8932 dirty=False branch=HEAD>
config {'version_scheme': 'guess-next-dev', 'local_scheme': 'node-and-date'}
ep found: guess-next-dev
version 0.1.dev161
ep found: node-and-date
local_version +gb1a8932
0.1.dev161+gb1a8932

[RonnyPfannschmidt]

@paugier there is a warning about the worktree being shallow

real root /tmp/snek5000
/home/users/augier3pi/Dev/setuptools_scm/src/setuptools_scm/git.py:135: UserWarning: "/tmp/snek5000" is shallow and may cause errors
  warnings.warn(f'"{wd.path}" is shallow and may cause errors')

i believe its necessary to provide some additional tooling to protect peopel from that trap without failing

[RonnyPfannschmidt]

Based on the current details, I believe it's necessary to change the default from warning to failing on incomplete partial checkouts