11.0.0 build fails if trove-classifiers is present

[sthen]

I'm attempting to build Pillow 11.0.0 to update our packages and it fails if trove-classifiers is also installed. Pillow 10.4.0 is ok in the same situation. Do you have any suggestions please - is this a problem with the new Pillow release or am I doing something wrong? Thanks.

Tested on OpenBSD -current with python 3.11.10, tried both setuptools 68.0.0 and 69.5.1, trove-classifiers 2024.4.10 and 2024.10.13.

* Getting build dependencies for wheel...
WARNING setuptools_scm._integration.setuptools pyproject.toml does not contain a tool.setuptools_scm section
/usr/local/lib/python3.11/site-packages/setuptools/config/pyprojecttoml.py:66: _BetaConfiguration: Support for `[tool.setuptools]` in `pyproject.toml` is still *beta*.
  config = read_configuration(filepath, True, ignore_option_errors, dist)
configuration error: `project.classifiers[1]` must be trove-classifier
DESCRIPTION:
    `PyPI classifier <https://pypi.org/classifiers/>`_.

GIVEN VALUE:
    "License :: OSI Approved :: CMU License (MIT-CMU)"

OFFENDING RULE: 'format'

DEFINITION:
    {
        "type": "string",
        "format": "trove-classifier"
    }
Traceback (most recent call last):
  File "/usr/local/lib/python3.11/site-packages/pyproject_hooks/_in_process/_in_process.py", line 353, in <module>
    main()
  File "/usr/local/lib/python3.11/site-packages/pyproject_hooks/_in_process/_in_process.py", line 335, in main
    json_out['return_val'] = hook(**hook_input['kwargs'])
                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/pyproject_hooks/_in_process/_in_process.py", line 118, in get_requires_for_build_wheel
    return hook(config_settings)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/setuptools/build_meta.py", line 341, in get_requires_for_build_wheel
    return self._get_build_requires(config_settings, requirements=['wheel'])
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/setuptools/build_meta.py", line 323, in _get_build_requires
    self.run_setup()
  File "/usr/local/lib/python3.11/site-packages/setuptools/build_meta.py", line 338, in run_setup
    exec(code, locals())
  File "<string>", line 1034, in <module>
  File "/usr/local/lib/python3.11/site-packages/setuptools/__init__.py", line 107, in setup
    return distutils.core.setup(**attrs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/setuptools/_distutils/core.py", line 159, in setup
    dist.parse_config_files()
  File "/usr/local/lib/python3.11/site-packages/setuptools/dist.py", line 898, in parse_config_files
    pyprojecttoml.apply_configuration(self, filename, ignore_option_errors)
  File "/usr/local/lib/python3.11/site-packages/setuptools/config/pyprojecttoml.py", line 66, in apply_configuration
    config = read_configuration(filepath, True, ignore_option_errors, dist)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/setuptools/config/pyprojecttoml.py", line 128, in read_configuration
    validate(subset, filepath)
  File "/usr/local/lib/python3.11/site-packages/setuptools/config/pyprojecttoml.py", line 55, in validate
    raise ValueError(f"{error}\n{summary}") from None
ValueError: invalid pyproject.toml config: `project.classifiers[1]`.
configuration error: `project.classifiers[1]` must be trove-classifier

ERROR Backend subprocess exited when trying to invoke get_requires_for_build_wheel

[aclark4life]

The trove classifier is new, if that helps, as of #7942

[sthen]

oops, sorry - I was mistaken with my testing. It is indeed only seen with the older trove-classifiers version; updating to 2024.10.13 did fix it. I suppose not a bug then.

[hugovk]

Good to hear :)