First read the overall project contributing guidelines. These are all included in the qiskit documentation:
https://qiskit.org/documentation/contributing_to_qiskit.html
In addition to the general guidelines there are specific details for contributing to retworkx, these are documented below.
Once you've made a code change, it is important to verify that your change does not break any existing tests and that any new tests that you've added also run successfully. Before you open a new pull request for your change, you'll want to run the test suite locally.
The easiest way to run the test suite is to use
tox. You can install tox
with pip: pip install -U tox. Tox provides several advantages, but the
biggest one is that it builds an isolated virtualenv for running tests. This
means it does not pollute your system python when running.
Note, if you run tests outside of tox that you can not run the tests from the root of the repo, this is because retworkx packaging shim will conflict with imports from retworkx the installed version of retworkx (which contains the compiled extension).
Just like with tests building documentation is done via tox. This will handle compiling retworkx, installing the python dependencies, and then building the documentation in an isolated venv. You can run just the docs build with:
tox -edocs
which will output the html rendered documentation in docs/build/html which
you can view locally in a web browser.