Using `requires_python` skips GraalPy identifiers

[mayeut]

Description

Found while testing 3.0.0b1 on pybase64 https://github.com/mayeut/pybase64/actions/runs/15225239809/job/42826448795

Adding graalpy to enable in pyproject.toml had no effect on the build because it's filtered by requires_python:

cibuildwheel/cibuildwheel/selector.py

Lines 75 to 84 in 327f5c3

	def __call__(self, build_id: str) -> bool:
	# Filter build selectors by python_requires if set
	if self.requires_python is not None:
	py_ver_str = build_id.split("-")[0]
	py_ver_str = py_ver_str.removesuffix("t")
	major = int(py_ver_str[2])
	minor = int(py_ver_str[3:])
	version = Version(f"{major}.{minor}.99")
	if not self.requires_python.contains(version):
	return False

The requires_python filter expects build identifier to be in the form f{impl}{pyver}t? but for GraalPy, the version used is not the one of Python & it's being filtered out.

Build log

https://github.com/mayeut/pybase64/actions/runs/15225239809/job/42826448795

CI config

https://github.com/mayeut/pybase64/blob/graalpy/.github/workflows/build-upload.yml

[mayeut]

IMHO, we should either:

• move the build identifier to gp311 like is done for PyPy if we don't expect to be building multiple ABIs for the same version of Python (from discussion in Support GraalPy #1538, I understand we'll probably have to support multiple ABIs for a single python version) .
• if we expect to build multiple ABIs, we should probably rework identifiers to use something that's more like the ABI tag (already the case for CPython but not for PyPy and GraalPy). We might not want to do this now as it might break PyPy workflows or only do this for GraalPy. Implemented in fix: rename gp242 identifier to gp311_242 #2411
• add the python version explicitly when calling the build selector (it's in the toml list but not yet part of GenericPythonConfiguration)