Update the init-pants action to work with scie-pants.

[benjyw]

No description provided.

[benjyw]

Note that to keep it simple, this new version doesn't support the old ./pants-based initialization.

If we want to avoid people haphazardly upgrading the action without first having switched to scie-pants, we can rename it, or give it a new version scheme.

[benjyw]

Am manually testing this, but reviews welcome.

[cognifloyd]

I haven't used scie-pants yet. These changes look sane, I just have a few questions.

Does adding a description to inputs work now? There are some places that take a description, and others that don't. I believe I ran into issues with reusable workflows not allowing it, so I'm guessing that actions metadata allows it. Have you tested using this anywhere? Maybe in a PR in the example-python repo?

[benjyw]

I'm testing this out, but I believe descriptions work.

[stuhood]

Shouldn't the interpreter version be tied to the Pants version, rather than to scie-pants version? Or does that not matter in this case because scie-pants is doing the parsing and can emit that for you?

[jsirois]

The latter:
https://github.com/pantsbuild/scie-pants/blob/7fc1471d6d0d66615fb0217459d5942cd161a799/tools/src/scie_pants/configure_pants.py#L120

Since scie-pants installs pantsbuild.pants in a venv it has to know the appropriate version of the hermetic PBS to use to do that install. When Pants switches distribution model to scie / PEX, if it chooses the (loose) scie route, Pants can completely control the Python it uses without letting scie-pants know. At that point this action will need to be updated to deal with that new state of the world.

[cognifloyd]

Thanks for adding the interpreter step back. I see one typo, and then LGTM