How to use flake8 plugins with pre-commit

flake8 plugins are usually distributed through a standalone python package on PyPI, e.g. flake8-print flake8-docstring.

In theory, I can locate where pre-commit’s venv is and install plugin packages into that venv by myself, but it’s really hacky and hard to be deterministically done for all other teammates and CI.

Does pre-commit provide some kind of mechanism to install extra packages into the venv it creates?

[asottile]

You’re looking for additional_dependencies.

[jnns]

Please excuse me for commenting on a closed ticket but I have a question that is related to this issue and you hopefully can clear up easily.

Right now, our flake8 version-pins that we have in requirements.txt are duplicated in .pre-commit-config.yaml (see below). How do you make sure that they’re not getting out of sync?

repos:
  - repo: https://gitlab.com/pycqa/flake8
    rev: '3.7.9'
    hooks:
    -   id: flake8
        additional_dependencies: [
            'flake8-bugbear==19.8.0',
            'flake8-coding==1.3.2',
            'flake8-comprehensions==3.0.1',
            'flake8-debugger==3.2.1',
            'flake8-deprecated==1.3',
            'flake8-docstrings==1.5.0',
            'flake8-isort==2.7.0',
            'flake8-pep3101==1.2.1',
            'flake8-polyfill==1.0.2',
            'flake8-print==3.1.4',
            'flake8-quotes==2.1.1',
            'flake8-string-format==0.2.3',
        ]
  - repo: https://github.com/python/black
    rev: 19.10b0
    hooks:
      - id: black
        language_version: python3.7

A perhaps more elegant solution could be to use a repository local hook. That way, no additional_dependencies need to be specified. The problem with this approach is that I’d need to hardcode the path to the projects virtualenv into .pre-commit-config.yaml and this path is not necessarily the same on my colleagues computers.

Is there an easy solution to this that i’m overlooking?