Use calendar versioning for Python package

Question

I prefer the calendar versioning scheme (see calver.org) over the semantic approach. But when I use calendar versioning in a Python package, PyPI removes the zero padding in the month. For example, in setup.py, if the version number is declared as version='19.03' then PyPI hosts the package as 19.3 (no zero padding).

Is there a way to force PyPI to acknowledge the zero-padded month or is the YYYY.0M scheme not supported for Python packages?

Answer 1

Yes, it's possible. The issue isn't PyPI, it's the way setuptools normalizes the version number when building a distribution.

Take this simple setup.py which defines a minimal package:

from setuptools import setup

setup(
    name='calver-test',
    version='2019.03.29',
    packages=[],
)

If you run python setup.py sdist, this will produce a file calver-test-2019.3.29.tar.gz that has the following structure:

calver-test-2019.3.29
├── PKG-INFO
├── calver_test.egg-info
│   ├── PKG-INFO
│   ├── SOURCES.txt
│   ├── dependency_links.txt
│   └── top_level.txt
├── setup.cfg
└── setup.py

If you manually unpack the tar.gz file, modify the occurrences of 2019.3.29 to 2019.03.29 in the PKG-INFO files, and re-pack it into a file named calver-test-2019.03.29.tar.gz, and upload it to PyPI, it will retain the zero padding.

Example here: https://pypi.org/project/calver-test/2019.03.29/

Obviously this process isn't ideal if this is your intended behavior, so perhaps it would make sense to open an issue on the setuptools issue tracker.