Reading Python classifiers from pyproject.toml

[henryiii]

How would this feature be useful?

We could convert python classifiers to a Python version list.

Describe the solution you'd like

Here's the current way to do it:

ALL_PYTHONS = [
    c.split()[-1]
    for c in nox.project.load_toml("pyproject.toml")["project"]["classifiers"]
    if c.startswith("Programming Language :: Python :: 3.")
]

Describe alternatives you've considered

No response

Anything else?

No response

[o-moe]

I just started utilizing nox and was looking for a way to get rid of the code duplication regarding the specified Python requirement from pyproject.toml and nox. For me, I was more looking into a way to use requires-python instead of the classifiers (since they are optional and requires-python is not). But this would work as well.

BTW: This could add great value to the documentation.

Keep up the great work!

[henryiii]

I think it would be fine to fall back to that if classifier are missing, but classifiers have an upper bound, while you should never put an upper cap for requires-Python.