Change --min-py-version behavior & always set python_requires

[mxr]

• Replace --min-py3-version with --min-py-version
• Change how the min version is determined; use --min-py-version as the source of truth if supplied, otherwise infer it
• Always set python_requires

Resolves #178

[asottile]

sorry it's been a while -- haven't gotten around to this. at the very least we'll need to keep the old option and have it be an alias to the new option (perhaps with a warning?)

[mxr]

at the very least we'll need to keep the old option and have it be an alias to the new option (perhaps with a warning?)

Perhaps we split this into multiple releases

Release 1: Add a --min-py-version flag which is used to override every other setting. That flag is exclusive with --min-py3-version
Release 2: Add a warning when --min-py3-version is used
Release 3: Drop --min-py3-version entirely, change the logic to act like what's in this PR
Release 4: Ensure --min-py-version>2, delete py2 code? Too heavy-handed?

[asottile]

I think simpler would be to just remove the py2 code and make --min-py3-version an alias to --min-py-version and disallow anything less than 2 -- and release that as a major version (then later remove the --min-py3-version option)

[mxr]

OK, so in cases where python_requires >= 2.7 - would the tool just promote that to the version in --min-py-version, regardless of whether or not it's set explicitly?

[asottile]

yep! intentionally removing any support for python 2.x packages

[mxr]

OK. Same for tox.ini envlist & classifiers too?

[asottile]

yep yep

[mxr]

Dropping py2 support and enforcing that --min-py-version takes precedence is kind of complicated so let me split up the PRs

[asottile]

I think this one is not quite right -- I think the defaulting is happening too early so it's ignoring all the tox / etc. settings?

[mxr]

Ah you're right the logic I have is "specify nothing: minimum is min(3.7, python_requires minimum, tox minimum, ...)" not "[...] max(3.7, [...]"