argon2-cffi-bindings/.github/CONTRIBUTING.md

How To Contribute

First off, thank you for considering contributing to argon2-cffi-bindings! It's people like you who make it such a great tool for everyone.

This document intends to make contribution more accessible by codifying tribal knowledge and expectations. Don't be afraid to open half-finished PRs, and ask questions if something is unclear!

Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms. Please report any harm to Hynek Schlawack in any way you find appropriate.

Workflow

• No contribution is too small! Please submit as many fixes for typos and grammar bloopers as you can!
• Try to limit each pull request to one change only.
• Since we squash on merge, it's up to you how you handle updates to the main branch. Whether you prefer to rebase on main or merge main into your branch, do whatever is more comfortable for you.
• Always add tests and docs for your code. This is a hard rule; patches with missing tests or documentation can't be merged.
• Make sure your changes pass our CI. You won't get any feedback until it's green unless you ask for it.
• Once you've addressed review feedback, make sure to bump the pull request with a short note, so we know you're done.
• Don’t break backwards compatibility.

Local Development Environment

You can (and should) run our test suite using tox. However, you’ll probably want a more traditional environment as well.

First, create a virtual environment so you don't break your system-wide Python installation. We recommend using the Python version from the .python-version-default file in project's root directory.

If you're using direnv, you can automate the creation of a virtual environment with the correct Python version by adding the following .envrc to the project root after you've cloned it to your computer:

layout python python$(cat .python-version-default)

If you're using tools that understand .python-version files like pyenv does, you can make it a link to the .python-version-default file.

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Next, fork the repository on GitHub and get an up-to-date checkout:

$ git clone git@github.com:<your-username>/argon2-cffi-bindings.git

or if you want to use git via https:

$ git clone https://github.com/<your-username>/argon2-cffi-bindings.git

Change into the newly created directory and activate your virtual environment

First you have to make sure that our Argon2 git submodule is up-to-date:

$ cd argon2-cffi-bindings
$ git submodule init     # initialize git submodule mechanics
$ git submodule update   # update the vendored Argon2 C library to the version we are packaging

Now an editable version of argon2-cffi-bindings along with its test requirements can be installed as usual:

$ python -Im pip install --upgrade pip setuptools cffi  # PLEASE don't skip this step
$ python -Im pip install -e '.[dev]'

At this point,

$ python -m pytest

should work and pass.

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When working on src/_argons_cffi_bindings/_ffi_build.py, it makes sense to regularly delete the build directory along with the created binary in src/_argons_cffi_bindings (e.g. on macOS and Linux, it's called _ffi.abi3.so) to ensure it's built fresh.

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To avoid committing code that violates our style guide, we strongly encourage you to install pre-commit ¹ hooks:

$ pre-commit install

You can also run them anytime (as our tox does) using:

$ pre-commit run --all-files

Code

• Obey PEP 8 and PEP 257. We use the """-on-separate-lines style for docstrings:

  def func(x):
      """
      Do something.
  
      :param str x: A very important parameter.
  
      :rtype: str
      """
  

• If you add or change public APIs, tag the docstring using .. versionadded:: 16.0.0 WHAT or .. versionchanged:: 16.2.0 WHAT.

• We use Ruff to sort our imports and format our code with a line length of 79 characters. As long as you run our full tox suite before committing, or install our pre-commit hooks (ideally you'll do both – see Local Development Environment above), you won't have to spend any time on formatting your code at all. If you don't, CI will catch it for you – but that seems like a waste of your time!

Tests

• Write your asserts as expected == actual to line them up nicely:

  x = f()
  
  assert 42 == x.some_attribute
  assert "foo" == x._a_private_attribute
  

• To run the test suite, all you need is a recent tox. It will ensure the test suite runs with all dependencies against all Python versions just as it will in our CI. If you lack some Python versions, you can can always limit the environments like tox -e py38,py39, or make it a non-failure using tox --skip-missing-interpreters.

  In that case you should look into asdf or pyenv, which make it very easy to install many different Python versions in parallel.

• Write good test docstrings.

Documentation

• Use semantic newlines in [Markdown*] files (files ending in .md):

  This is a sentence.
  This is another sentence.
  

Changelog

If your change is noteworthy, there needs to be a changelog entry in CHANGELOG.md.

• As with other docs, please use semantic newlines in the changelog.

• Wrap symbols like modules, functions, or classes into backticks so they are rendered in a monospace font.

• Wrap arguments into asterisks like in docstrings: Added new argument *an_argument*.

• If you mention functions or other callables, add parentheses at the end of their names: _argon2_cffi_bindings.func() or _argon2_cffi_bindings.Class.method(). This makes the changelog a lot more readable.

• Prefer simple past tense or constructions with "now". For example:

  • Added _argon2_cffi_bindings.func().
  • _argon2_cffi_bindings.func() now doesn't crash the Large Hadron Collider anymore when passed the foobar argument.

Example entries:

Added `_argon2_cffi_bindings.func()`.
The feature really *is* awesome.

or:

`_argon2_cffi_bindings.func()` now doesn't crash the Large Hadron Collider anymore when passed the *foobar* argument.
The bug really *was* nasty.

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1. pre-commit should have been installed into your virtualenv automatically when you ran pip install -e '.[dev]' above. If pre-commit is missing, your probably need to run pip install -e '.[dev]' again. ↩︎