Integrations

We leverage all the existing flake8 infrastructure and tools. There are different integrations for your workflow.

Hooks

  • pytest-flake8 to run style checks alongside with tests

  • pre-commit to run flake8 before all commits locally

  • pronto-flake8 to post inline-comments with violations during code-review inside your CI

Editors

Note, that some editors might need to disable our own formatter and set the default formatter with format = default in your configuration.

Extras

There are some tools that are out of scope of this linter, however they are super cool. And should definitely be used!

Things we highly recommend to improve your code quality:

  • mypy runs type checks on your python code. Finds tons of issues. Makes your code better, improves you as a programmer. You must use, and tell your friends to use it too

  • layer-linter allows you to define application layers and ensure you do not break that contract. Absolutely must have

  • xenon and radon allow you to automate some code metrics check

  • cohesion tool to measure code cohesion, works for most of the times. We recommend to use it as a reporting tool

  • vulture allows you to find unused code. Has some drawbacks, since there is too many magic in python code. But, it is still very useful tool for the refactoring

Stubs

If you are using stub .pyi files and flake8-pyi extensions you might need to ignore several violations that are bundled with this linter.

You can still do it on per-file bases as usual. Use *.pyi glob to list ignored violations:

per-file-ignores =
  *.pyi: WPS428, WPS604

You can look at the returns project as an example.

pylint

We are not related to the pylint project. Yes, we know that it is awesome. But, it has some drawbacks:

  1. It makes a lot of type assertions. And does it incorrectly. Since we use mypy there is no sense in this feature. Without this feature a lot of other pylint features looses its point as well

  2. There are less exisitng plugins for pylint than for flake8

  3. It uses custom ast parser and library, which can be problematic

  4. It is not strict enough for us. So, we will have to write our own plugin no matter what platform we use

However, it is important to mention that pylint is less radical and more classic in its rules.

Auto-formatters

Autoformatters are very simple tools to do just a one thing: reformat some basic stuff in your code like quotes, commas, and line length.

The difference between a linter and auto-formatter is huge:

  • auto-formatters pretties your code a little bit

  • linters force you to write beautiful and correct code

For example, auto-formatters won’t tell you that your code is too complex. When your linter will (in case it is a good linter).

Autoformatters are also useless when dealing with rewriting actually bad code. Like code with bad variable names, unreachable branches, statements that have no effect.

We in wemake.services believe that these kind of tools are not required, because a good linter will just not let your badly formated code pass the CI, so there would be no junk to reformat! All code is perfectly formated all the time.

Rely on strict linters, not auto-formatters.

However, if you still want to use some autoformatter together with wemake-python-styleguide we have made some reasearch to help you!

autopep8

autopep8 is the best choice for wemake-python-styleguide users.

Is officially supported in way that all code written inside wemake-python-styleguide is tested to be valid autopep8 code. But, not the other way around.

Since wemake-python-styleguide is the strictest linter it cannot be pleased by outputs of autopep8 in 100% of cases all by itself. Most likely, you will need to refactor a little bit more manually (brainly!) to please wemake-python-styleguide after autopep8 formatting is done.

There are also plugins for IDEs to run autopep8 on safe:

isort

isort is a great tool to sort your imports. We already use it to validate that your imports are correct. We recommend to use isort and officially and support it in a way that all valid wemake-python-styleguide code is valid isort code. But, not the other way around.

You might be required to refactor your code manually after isort reformat to make wemake-python-styleguide happy.

isort can also be invoked as a command line tool to fix all your import problems for you.

We recommend to run isort after autopep8. They are also compatible.

There are also plugins for IDEs to run isort on safe:

You can find the configuration we use in setup.cfg in this repository.

yapf

This a very complex autoformatter written by Google. It has like lots of configuration options!

We were not successful enough to configure it in a way that our style is respected. The main problems are with new lines and trailing commas: sometimes they are added, sometimes removed.

If you have a working configuration for both yapf and wemake-python-styleguide, please, let us know!

black

wemake-python-styleguide is not compatible to black. Let’s go deeper and see why.

black itself is actually not compatible with PEP8 and flake8 (docs), that’s why it is not compatible with wemake-python-styleguide either. Here are the violations that black produces:

  • Quotes: for some reasons black uses " that almost no one uses in the python world

  • Trailing commas: black strips trailing commas and this makes adding new code harder to review, since your git diff is poluted by a comma change, the sad thing that tailing commas as a best-practice are quite popular in python code

  • Line length. Violating rules by 10%-15% is not ok. You either violate them or not. black violates line-length rules.

And there’s no configuration to fix it! Shame, that official python-org product violates the community standards and not enforcing them.