fails on test_setuptools_prepare_metadata_for_build_wheel with Python 3.9

[mcepl]

pyproject-api/tests/test_frontend_setuptools.py

Line 78 in 0f0239c

assert values == ["requests (>2)", "magic (>3)"]

Tests passes with 3.10, but not with 3.9:

[   12s] _______________ test_setuptools_prepare_metadata_for_build_wheel _______________
[   12s] 
[   12s] frontend_setuptools = <pyproject_api._via_fresh_subprocess.SubprocessFrontend object at 0x7fba9b7caa90>
[   12s] tmp_path = PosixPath('/tmp/pytest-of-abuild/pytest-13/test_setuptools_prepare_metada0')
[   12s] 
[   12s]     def test_setuptools_prepare_metadata_for_build_wheel(frontend_setuptools: SubprocessFrontend, tmp_path: Path) -> None:
[   12s]         meta = tmp_path / "meta"
[   12s]         result = frontend_setuptools.prepare_metadata_for_build_wheel(metadata_directory=meta)
[   12s]         dist = Distribution.at(str(result.metadata))
[   12s]         assert list(dist.entry_points) == [EntryPoint(name="demo_exe", value="demo:a", group="console_scripts")]
[   12s]         assert dist.version == "1.0"
[   12s]         assert dist.metadata["Name"] == "demo"
[   12s]         values = [v for k, v in dist.metadata.items() if k == "Requires-Dist"]  # type: ignore
[   12s]         # ignore because "PackageMetadata" has no attribute "items"
[   12s] >       assert values == ["requests (>2)", "magic (>3)"]
[   12s] E       AssertionError: assert ['magic (>3)'...equests (>2)'] == ['requests (>... 'magic (>3)']
[   12s] E         At index 0 diff: 'magic (>3)' != 'requests (>2)'
[   12s] E         Full diff:
[   12s] E         - ['requests (>2)', 'magic (>3)']
[   12s] E         + ['magic (>3)', 'requests (>2)']

Complete build log with all details of versions of packages used and steps taken to reproduce.

[gaborbernat]

PR welcome 🤗