Missing tomli module with v6.3.0

[bonastreyair]

Since the release of setuptools_scm v6.3.0 a few minutes ago, it breaks pre-commit failing on the following error:

ModuleNotFoundError: No module named 'tomli'

That already appeared with v6.1.1 see #608

Log:

[INFO] Installing environment for https://github.com/psf/black.
[INFO] Once installed this environment will be reused.
[INFO] This may take a few minutes...
An unexpected error has occurred: CalledProcessError: command: ('/home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/bin/python', '-mpip', 'install', '.')
return code: 1
expected return code: 0
stdout:
    Processing /home/runner/.cache/pre-commit/reposyqhxl1x
      Installing build dependencies: started
      Installing build dependencies: finished with status 'done'
      Getting requirements to build wheel: started
      Getting requirements to build wheel: finished with status 'done'
        Preparing wheel metadata: started
        Preparing wheel metadata: finished with status 'error'
    
stderr:
      DEPRECATION: A future pip version will change local packages to be built in-place without first copying to a temporary directory. We recommend you use --use-feature=in-tree-build to test your packages with this new behavior before it becomes the default.
       pip 21.3 will remove support for this functionality. You can find discussion regarding this at https://github.com/pypa/pip/issues/7555.
        ERROR: Command errored out with exit status 1:
         command: /home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/bin/python /home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/lib/python3.7/site-packages/pip/_vendor/pep517/in_process/_in_process.py prepare_metadata_for_build_wheel /tmp/tmpr9paf95u
             cwd: /tmp/pip-req-build-ipmmr8oz
        Complete output (32 lines):
        /tmp/pip-build-env-g8y0052r/overlay/lib/python3.7/site-packages/setuptools_scm/git.py:94: UserWarning: "/tmp/pip-req-build-ipmmr8oz" is shallow and may cause errors
          warnings.warn(f'"{wd.path}" is shallow and may cause errors')
        Traceback (most recent call last):
          File "/home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/lib/python3.7/site-packages/pip/_vendor/pep517/in_process/_in_process.py", line 349, in <module>
            main()
          File "/home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/lib/python3.7/site-packages/pip/_vendor/pep517/in_process/_in_process.py", line 331, in main
            json_out['return_val'] = hook(**hook_input['kwargs'])
          File "/home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/lib/python3.7/site-packages/pip/_vendor/pep517/in_process/_in_process.py", line 151, in prepare_metadata_for_build_wheel
            return hook(metadata_directory, config_settings)
          File "/tmp/pip-build-env-g8y0052r/overlay/lib/python3.7/site-packages/setuptools/build_meta.py", line 166, in prepare_metadata_for_build_wheel
            self.run_setup()
          File "/tmp/pip-build-env-g8y0052r/overlay/lib/python3.7/site-packages/setuptools/build_meta.py", line 150, in run_setup
            exec(compile(code, __file__, 'exec'), locals())
          File "setup.py", line 111, in <module>
            "black-primer=black_primer.cli:main",
          File "/tmp/pip-build-env-g8y0052r/overlay/lib/python3.7/site-packages/setuptools/__init__.py", line 153, in setup
            return distutils.core.setup(**attrs)
          File "/opt/hostedtoolcache/Python/3.7.11/x64/lib/python3.7/distutils/core.py", line 108, in setup
            _setup_distribution = dist = klass(attrs)
          File "/tmp/pip-build-env-g8y0052r/overlay/lib/python3.7/site-packages/setuptools/dist.py", line 456, in __init__
            k: v for k, v in attrs.items()
          File "/opt/hostedtoolcache/Python/3.7.11/x64/lib/python3.7/distutils/dist.py", line 292, in __init__
            self.finalize_options()
          File "/tmp/pip-build-env-g8y0052r/overlay/lib/python3.7/site-packages/setuptools/dist.py", line 807, in finalize_options
            ep(self)
          File "/tmp/pip-build-env-g8y0052r/overlay/lib/python3.7/site-packages/setuptools_scm/integration.py", line 90, in infer_version
            config = Configuration.from_file(dist_name=dist_name)
          File "/tmp/pip-build-env-g8y0052r/overlay/lib/python3.7/site-packages/setuptools_scm/config.py", line 181, in from_file
            defn = _load_toml(data)
          File "/tmp/pip-build-env-g8y0052r/overlay/lib/python3.7/site-packages/setuptools_scm/config.py", line 53, in _lazy_tomli_load
            from tomli import loads
        ModuleNotFoundError: No module named 'tomli'
        ----------------------------------------
    WARNING: Discarding file:///home/runner/.cache/pre-commit/reposyqhxl1x. Command errored out with exit status 1: /home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/bin/python /home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/lib/python3.7/site-packages/pip/_vendor/pep517/in_process/_in_process.py prepare_metadata_for_build_wheel /tmp/tmpr9paf95u Check the logs for full command output.
    ERROR: Command errored out with exit status 1: /home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/bin/python /home/runner/.cache/pre-commit/reposyqhxl1x/py_env-python3/lib/python3.7/site-packages/pip/_vendor/pep517/in_process/_in_process.py prepare_metadata_for_build_wheel /tmp/tmpr9paf95u Check the logs for full command output.

[ssbarnea]

My impression is that this is a bug in black and many other libraries which are missing to mention toml extra, especially as it needs to be mentioned int 2-3 different places: setup.cfg, setup.py and pyproject.toml. I do expect a huge number of people to hit that.

@RonnyPfannschmidt Is that really a bug in newer setuptools-scm or really the way it was used?

[RonnyPfannschmidt]

@ssbarnea we are going to make toml the default now - at some point it will have to be anyway and now not adding it breaks pipelines