Archival information is there, but setuptools_scm can't read it

[ozagordi]

Hi.

I'm trying to use the plugin for a project of mine. I followed the instructions, created the two hidden files, tagged and pushed to GitHub. When I download the archive, the right information are written into .git_archival.txt

(minvardevel) ➜  /private/tmp/MinVar-1.0.0-alpha  cat .git_archival.txt
ref-names: tag: v1.0.0-alpha, scm_git_archive

My setup.py reads as indicated in the instructions, it seems to me.

(minvardevel) ➜  /private/tmp/MinVar-1.0.0-alpha  head -7 setup.py
#!/usr/bin/env python

import setuptools

setuptools.setup(
    use_scm_version=True,
    setup_requires=['setuptools_scm', 'setuptools_scm_git_archive'],
    ...

But if I try to run it, it complains that it cannot read the version

(minvardevel) ➜  /private/tmp/MinVar-1.0.0-alpha  python setup.py develop
zip_safe flag not set; analyzing archive contents...
zip_safe flag not set; analyzing archive contents...

Installed /private/tmp/MinVar-1.0.0-alpha/.eggs/setuptools_scm_git_archive-1.0-py3.6.egg

Installed /private/tmp/MinVar-1.0.0-alpha/.eggs/setuptools_scm_git_archive-0-py3.6.egg
Searching for setuptools_scm
Reading https://pypi.python.org/simple/setuptools_scm/
Downloading https://pypi.python.org/packages/fb/22/1f1c3b223425351cf499d04ecf9673d12c4adf1c971a0d72b9cf919d4d6a/setuptools_scm-1.15.5-py3.6.egg#md5=5c831eb5f62b4503ae76090fda1b70f0
Best match: setuptools-scm 1.15.5
Processing setuptools_scm-1.15.5-py3.6.egg
Moving setuptools_scm-1.15.5-py3.6.egg to /private/tmp/MinVar-1.0.0-alpha/.eggs

Installed /private/tmp/MinVar-1.0.0-alpha/.eggs/setuptools_scm-1.15.5-py3.6.egg
Traceback (most recent call last):
  File "setup.py", line 33, in <module>
    'minvar = minvar.__main__:main'
  File "/Users/ozagordi/miniconda3/envs/minvardevel/lib/python3.6/distutils/core.py", line 108, in setup
    _setup_distribution = dist = klass(attrs)
  File "/Users/ozagordi/miniconda3/envs/minvardevel/lib/python3.6/site-packages/setuptools/dist.py", line 323, in __init__
    _Distribution.__init__(self, attrs)
  File "/Users/ozagordi/miniconda3/envs/minvardevel/lib/python3.6/distutils/dist.py", line 281, in __init__
    self.finalize_options()
  File "/Users/ozagordi/miniconda3/envs/minvardevel/lib/python3.6/site-packages/setuptools/dist.py", line 392, in finalize_options
    ep.load()(self, ep.name, value)
  File "/private/tmp/MinVar-1.0.0-alpha/.eggs/setuptools_scm-1.15.5-py3.6.egg/setuptools_scm/integration.py", line 22, in version_keyword
  File "/private/tmp/MinVar-1.0.0-alpha/.eggs/setuptools_scm-1.15.5-py3.6.egg/setuptools_scm/__init__.py", line 119, in get_version
  File "/private/tmp/MinVar-1.0.0-alpha/.eggs/setuptools_scm-1.15.5-py3.6.egg/setuptools_scm/__init__.py", line 97, in _do_parse
LookupError: setuptools-scm was unable to detect version for '/private/tmp/MinVar-1.0.0-alpha'.

Make sure you're either building from a fully intact git repository or PyPI tarballs. Most other sources (such as GitHub's tarballs, a git checkout without the .git folder) don't contain the necessary metadata and will not work.

For example, if you're using pip, instead of https://github.com/user/proj/archive/master.zip use git+https://github.com/user/proj.git#egg=proj

To me it looks like setuptools_scm is not falling back on setuptools_scm_git_archive, but why?
What am I doing wrong?

I would like to access the version info programmatically, like having the version info consumed by argparser, argument -v.

Thanks.

---

Update

If I change the content of my .git_archival.txt to v1.0.alpha, then python setup.py develop works fine. Accessing the version returns 1.0a0. I understand now that the reason for failing was in the format of the tag, although I'm a bit surprised that it failed completely rather than emitting some warning. Something that might be worth stressing in the README, together with the fact that setting the environment variable SETUPTOOLS_SCM_DEBUG=TRUE let setup print more info.