nitpick

Flake8 plugin to enforce the same lint configuration (flake8, isort, mypy, pylint) across multiple Python projects.

A "nitpick code style" is a TOML file with settings that should be present in config files from other tools. E.g.:

• pyproject.toml and setup.cfg (used by flake8, black, isort, mypy);
• .pylintrc (used by pylint config);
• more files to come.

---

• Installation and usage
• Style file
• setup.cfg

---

Installation and usage

To try the package, simply install it (in a virtualenv or globally, wherever) and run flake8:

$ pip install -U nitpick
$ flake8

You will see warnings if your project configuration is different than the default style file.

As a pre-commit hook

If you use pre-commit on your project, add this to the .pre-commit-config.yaml in your repository:

repos:
  - repo: https://github.com/andreoliwa/nitpick
    rev: v0.18.0
    hooks:
      # Run nitpick and several other flake8 plugins
      - id: nitpick-all
      # Check only nitpick errors, ignore other flake8 plugins
      - id: nitpick-only

Use one hook or the other (nitpick-all or nitpick-only), not both. To check all the other flake8 plugins that are installed with nitpick, see the pyproject.toml.

Style file

Configure your own style file

Change your project config on pyproject.toml, and configure your own style like this:

[tool.nitpick]
style = "https://raw.githubusercontent.com/andreoliwa/nitpick/v0.18.0/nitpick-style.toml"

You can set style with any local file or URL. E.g.: you can use the raw URL of a GitHub Gist.

You can also use multiple styles and mix local files and URLs:

[tool.nitpick]
style = ["/path/to/first.toml", "/another/path/to/second.toml", "https://example.com/on/the/web/third.toml"]

The order is important: each style will override any keys that might be set by the previous .toml file. If a key is defined in more than one file, the value from the last file will prevail.

Default search order for a style file

1. A file or URL configured in the pyproject.toml file, [tool.nitpick] section, style key, as described above.

2. Any nitpick-style.toml file found in the current directory (the one in which flake8 runs from) or above.

3. If no style is found, then the default style file from GitHub is used.

Style file syntax

A style file contains basically the configuration options you want to enforce in all your projects.

They are just the config to the tool, prefixed with the name of the config file.

E.g.: To configure the black formatter with a line length of 120, you use this in your pyproject.toml:

[tool.black]
line-length = 120

To enforce that all your projects use this same line length, add this to your nitpick-style.toml file:

["pyproject.toml".tool.black]
line-length = 120

It's the same exact section/key, just prefixed with the config file name ("pyproject.toml".)

The same works for setup.cfg. To configure mypy to ignore missing imports in your project:

[mypy]
ignore_missing_imports = true

To enforce all your projects to ignore missing imports, add this to your nitpick-style.toml file:

["setup.cfg".mypy]
ignore_missing_imports = true

Absent files

To enforce that certain files should not exist in the project, you can add them to the style file.

[nitpick.files.absent]
"some_file.txt" = "This is an optional extra string to display after the warning"
"another_file.env" = ""

Multiple files can be configured as above. The message is optional.

setup.cfg

Comma separated values

On setup.cfg, some keys are lists of multiple values separated by commas, like flake8.ignore.

On the style file, it's possible to indicate which key/value pairs should be treated as multiple values instead of an exact string. Multiple keys can be added.

[nitpick.files."setup.cfg"]
comma_separated_values = ["flake8.ignore", "isort.some_key", "another_section.another_key"]