peterjc/flake8-black

Broken toml import

Closed this issue · 5 comments

chris-bradley commented

Since Black 21.7b0, released earlier today, flake8-black breaks on an import error when used with a freshly installed environment. The issue is due to the following commit:
psf/black@7e1acb7
Since flake8-black imports toml without depending directly on it, freshly built environments fail with the following error:

Traceback (most recent call last):
  File "/home/circleci/.venv/lib/python3.6/site-packages/flake8/plugins/manager.py", line 157, in load_plugin
    self._load()
  File "/home/circleci/.venv/lib/python3.6/site-packages/flake8/plugins/manager.py", line 134, in _load
    self._plugin = self.entry_point.load()
  File "/home/circleci/.venv/lib/python3.6/site-packages/importlib_metadata/__init__.py", line 178, in load
    module = import_module(match.group('module'))
  File "/usr/local/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/home/circleci/.venv/lib/python3.6/site-packages/flake8_black.py", line 11, in <module>
    import toml
ModuleNotFoundError: No module named 'toml'

There are a few options to fix this:

  • Add a requirement for toml to requirements.txt.
  • Switch from using toml to using tomli.
    • You would also want to update requirements.txt to use black versions that depend upon tomli.
    • You would also need to update references to toml.decoder.TomlDecodeError to tomli.decoder.TOMLDecodeError. (Note the case change.)
  • Catch import errors of toml and import tomli instead, aliased to toml.
    • You would also need an import alias for the aforementioned case change in TomlDecodeError.
peterjc commented

Thank you for reporting this. I'm leaning to adding toml as an explicit dependency as a short term low risk fix.

Sigh. They had to release it on a Friday didn't they? There will probably be other bug reports in the ecosystem not seen until Monday morning (and then a fresh batch as more people try the new black on Monday).

chris-bradley commented

Thank you!

peterjc commented

Touch wood v0.2.2 fixes this for you, but I don't want to make any more dramatic changes prior to addressing the broken continuous integration (#34).

brianhelba commented

@peterjc I don't see how 65c9d57 fixes this issue, since only requirements.txt is changed.

You'll need to update install_requires in setup.py in order to give setuptools adequate metadata to fetch the dependency when installing with pip.

peterjc commented