Use tomllib/tomli for reading .toml configs

[mgorny]

Use the built-in tomllib module in Python 3.11 and the modern tomli package in older Python versions to read .toml configs instead of the unmaintained and broken toml package.

Fixes #599
Fixes #600

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[mgorny]

Rebased on top of poetry.

[Pierre-Sassoulas]

I think this depend on #612 to be really tested, could you rebase on it ?

The Python 3.11 change was merged in and this PR is being properly tested now.

[sambhav]

Thanks for this PR!

[mgorny]

Thanks!

[christianbundy]

This was a breaking change for our team, btw -- we're on Python 3.10 and have had toml installed, but updating to the latest version meant that our configuration file was ignored and so we got a bunch of unexpected errors:

WARNING: The pyproject.toml configuration file was ignored, because the `tomli` package is not installed.

Now that I understand what changed, it's a simple fix, but wanted to let y'all know that this wasn't 100% backward-compatible. Either way, thanks for the improvement -- I'm increasingly excited to join the Python 3.11 gang.

[sambhav]

@christianbundy how were you installing pydocstyle with toml support? Were you using pydocstyle[toml] ? If so, it should not have been a breaking change.

[christianbundy]

We're using pre-commit, here's the config we were using:

  - repo: https://github.com/pycqa/pydocstyle
    rev: 6.2.3 # previously using 6.1.1, upgrading caused errors
    hooks:
      - id: pydocstyle
        args:
          - --config=pyproject.toml
        additional_dependencies:
          - toml~=0.10.2

Should we have been doing this differently? I think maybe we could add pydocstyle[toml] as an additional dependency, but I think that would install pydocstyle twice? Not sure how that would work.

[sambhav]

@christianbundy you want the following -

pre-commit/pre-commit#1526 (comment)

[christianbundy]

Oh, nice! Thank you.

[mgorny]

@christianbundy you want the following -

pre-commit/pre-commit#1526 (comment)

Could someone ask upstream to include that in the official documentation? It's not the most predictable way of sorting this particular problem. Unfortunately, I can't do that since upstream likes banning people for no apparent reason.

[scottstanie]

Just to spell it out for any others, it took me a few tries to connect the comment above to what we need here. My .pre-commit.yaml now has

  - repo: https://github.com/PyCQA/pydocstyle
    rev: "6.3.0"
    hooks:
      - id: pydocstyle
        additional_dependencies: ['.[toml]']

and it made the tomli error go away