Trim contributing guide (#914)

It was mostly out of date - trying to document just the unchanging pieces.

Author: adamchainz

CONTRIBUTING.rst

@@ -2,141 +2,32 @@
 Contributing
 ============
 
-Contributions are welcome, and they are greatly appreciated! Every little bit
-helps, and credit will always be given.
+Run the tests
+-------------
 
-You can contribute in many ways:
+1. Install `tox <https://tox.wiki/en/latest/>`__.
 
-Types of Contributions
-----------------------
+2. Run a supported version of MySQL or MariaDB.
+   This is easiest with the official Docker images.
+   For example:
 
-Report Bugs
-~~~~~~~~~~~
+   .. code-block:: console
 
-Report bugs via `Github Issues
-<https://github.com/adamchainz/django-mysql/issues>`_.
+       docker run --detach --name mariadb -e MYSQL_ROOT_PASSWORD=hunter2 --publish 3306:3306 mariadb:10.7
 
-If you are reporting a bug, please include:
+3. Run the tests by passing environment variables with your connection parameters.
+   For the above Docker command:
 
-* Your versions of Django-MySQL, Django, and MySQL/MariaDB
-* Any other details about your local setup that might be helpful in
-  troubleshooting, e.g. operating system.
-* Detailed steps to reproduce the bug.
+   .. code-block:: console
 
-Fix Bugs
-~~~~~~~~
+      DB_HOST=127.0.0.1 DB_USER=root DB_PASSWORD='hunter2' tox -e py310-django40
 
-Look through the GitHub issues for bugs. Anything tagged with "bug"
-is open to whoever wants to implement it.
+  tox environments are split per Python and Django version.
 
-Implement Features
-~~~~~~~~~~~~~~~~~~
+  You can run a subset of tests by passing them after ``--`` like:
 
-Look through the GitHub issues for features. Anything tagged with "help wanted"
-and not assigned to anyone is open to whoever wants to implement it - please
-leave a comment to say you have started working on it, and open a pull request
-as soon as you have something working, so that Travis starts building it.
+  .. code-block:: console
 
-Issues without "help wanted" generally already have some code ready in the
-background (maybe it's not yet open source), but you can still contribute to
-them by saying how you'd find the fix useful, linking to known prior art, or
-other such help.
+    DB_HOST=127.0.0.1 DB_USER=root DB_PASSWORD='hunter2' tox -e py310-django40 -- tests/testapp/test_cache.py
 
-Write Documentation
-~~~~~~~~~~~~~~~~~~~
-
-Django-MySQL could always use more documentation, whether as part of the
-official Django-MySQL docs, in docstrings, or even on the web in blog posts,
-articles, and such. Write away!
-
-Submit Feedback
-~~~~~~~~~~~~~~~
-
-The best way to send feedback is to file an issue via `Github Issues
-<https://github.com/adamchainz/django-mysql/issues>`_.
-
-If you are proposing a feature:
-
-* Explain in detail how it would work.
-* Keep the scope as narrow as possible, to make it easier to implement.
-* Remember that this is a volunteer-driven project, and that contributions
-  are welcome :)
-* Link to any prior art, e.g. MySQL/MariaDB documentation that details the
-  necessary database features
-
-Get Started!
-------------
-
-Ready to contribute? Here's how to set up Django-MySQL for local development.
-
-1. Fork the Django-MySQL repo on GitHub.
-2. Clone your fork locally:
-
-   .. code-block:: sh
-
-       $ git clone [email protected]:your_name_here/django-mysql.git
-       $ cd django-mysql/
-
-3. Check you have a supported version of MySQL or MariaDB running and that the
-   settings in ``tests/settings.py`` will work for connecting. This involves
-   making sure you can connect from your terminal with the plain command
-   ``mysql`` with no options, i.e. as your current user.
-
-   On Ubuntu, this can be done with the commands below:
-
-   .. code-block:: sh
-
-       $ sudo apt-get install mysql-server-5.7
-       $ mysql -uroot -p -e "CREATE USER '$(whoami)'@localhost; GRANT ALL PRIVILEGES ON *.* TO '$(whoami)'@localhost;"
-       # Enter the password for root you set in the apt dialog
-
-   On Mac OS X, this can be done with something like:
-
-   .. code-block:: sh
-
-       $ brew install mariadb
-       $ mysql.server start
-       $ mysql -uroot -e "CREATE USER '$(whoami)'@localhost; GRANT ALL PRIVILEGES ON *.* TO '$(whoami)'@localhost;"
-
-   If you want to use a different user or add a password, you can patch the
-   settings file in your local install.
-
-5. Install ``tox`` and run the tests for Python 3.10 + Django 4.0:
-
-   .. code-block:: sh
-
-       $ python -m pip install tox
-       $ tox -e py310-django40
-
-6. To make changes, create a branch for local development:
-
-   .. code-block:: sh
-
-       $ git checkout -b name-of-your-bugfix-or-feature
-
-   ...and hack away!
-
-7. Commit your changes and push your branch to GitHub:
-
-   .. code-block:: sh
-
-       $ git add .
-       $ git commit -m "Your detailed description of your changes."
-       $ git push origin name-of-your-bugfix-or-feature
-
-8. Submit a pull request through the GitHub website. This will trigger the
-   Travis build which runs the tests against all supported versions of Python,
-   Django, and MySQL/MariaDB.
-
-Testing Tips
-------------
-
-To only run a particular test file, you can run with the path to that file:
-
-.. code-block:: sh
-
-    $ tox -- tests/testapp/test_some_feature.py
-
-You can also pass other pytest arguments through ``tox`` after the ``--``
-separator. There are lots of other useful features, most of which you can check
-out in the `pytest docs <http://docs.pytest.org/en/latest/>`_!
+  You can also pass other pytest arguments after the ``--``.