Specific Python patch versions (vX.Y.Z) are not respected?

[SyntaxColoring]

Describe the bug

If you have a config like this...

[gh-actions]
python =
    3.10.8: py3108
    3.10: py310

...and your GitHub Actions configuration installs 3.10.8, this plugin will select the py310 environment instead of the py3108 environment.

To Reproduce

GitHub Action snippet:

    - uses: actions/setup-python@v5
      with:
        python-version: 3.10.8

tox.ini snippet:

[testenv: py3108]
basepython = python3.10.8

[gh-actions]
python =
    3.8: py38
    3.9: py39
    3.10.8: py3108
    3.10: py310
    3.11: py311
    3.12: py312

The PR where I noticed this, showing the full configurations: pytest-dev/pytest-asyncio#817

And the specific job where I noticed this: https://github.com/pytest-dev/pytest-asyncio/actions/runs/8732675787/job/23960070899?pr=817

Expected behavior

I expect to be able to write major.minor.patch versions like 3.10.8 in my tox.ini's [gh-actions] section. If I write 3.10.8, I expect that to match a runner version of 3.10.8 but not 3.10.9. If I write just 3.10, I expect that to match a runner version of 3.10.8 or 3.10.9. If multiple entries in my tox.ini config match the runner version, I guess I expect the lexicographically first one to be used.

Additional context

N/A

[ymyzk]

Hello @SyntaxColoring. Thanks for filing a ticket!

The problem should be caused by the fact that tox-gh-actions doesn't expect major.minor.patch as a key of gh-actions.python at this point. Here's the relevant code:

tox-gh-actions/src/tox_gh_actions/plugin.py

Lines 182 to 184 in a6451af

	else:
	# Assume this is running on CPython
	return [major_minor_version, major_version]

I think it makes sense to add the patch version support to tox-gh-actions. If you're open to create a MR for this change, feel free to do so. I might not be able to find time to implement this improvement by myself right now.

[SyntaxColoring]

Yep, I'm happy to give it a shot. It'll probably be a while before I get around to it, too.