Add pypy and maybe graalpy support to `generate-ci`

[messense]

we can add a new cli option --python-implementation to select python impls to build wheels for, it should support these options:

• cpython (enabled by default)
• pypy
• graalpy (if we can upload graalpy wheels to pypi, need to check that)

https://github.com/PyO3/maturin/blob/main/src/ci.rs

[masklinn]

graalpy (if we can upload graalpy wheels to pypi, need to check that)

Aren't cffi wheels implementation independent?

So maybe that could just be based on the binding kind?

cpyext don't seem very encouraged ^{1 2} and e.g. documentation is basically nonexistent (and many old links are dead), it requires linking against pypy's headers and not linking against libpython, which I'm not sure pyo3 / maturin supports (I didn't really find any references to that anywhere), so I figured cffi was the more likely way to support pypy (and graal) if I wanted that.

[messense]

@masklinn Both PyPy and GraalPy are supported, see

• Support rust extensions for PyPy via cpyext pyo3#393
• Basic GraalPy Support pyo3#3247

[masklinn]

@masklinn Both PyPy and GraalPy are supported, see

• Support rust extensions for PyPy via cpyext pyo3#393
• Basic GraalPy Support pyo3#3247

Thanks for the correction, are there docs around for those? I didn’t find anything when looking around maturin’s docs hence my belief that cffi would be the most well trodden path for pypy and graal (I understand uniffi also works with pypy, I wasn’t clear if it would work with graal at all).