# Contributing

Contributions from the user community are welcome. See the `PETSc developers` documentation for general information on contributions.

New contributions to petsc4py must adhere with the coding standards. We use cython-lint for Cython and ruff for Python source codes. These can be installed using:

    $ python -m pip install -r src/binding/petsc4py/conf/requirements-lint.txt

If you are contributing Cython code, you can check compliance with:

    $ make cython-lint -C src/binding/petsc4py

For Python code, run:

    $ make ruff-lint -C src/binding/petsc4py

Python code can be auto-formatted using:

    $ make ruff-lint RUFF_OPTS='format' -C src/binding/petsc4py

New contributions to petsc4py must be tested. Tests are located in the `src/binding/petsc4py/test` folder. To add a new test, either add a new `test_xxx.py` or modify a pre-existing file according to the unittest specifications.

If you add a new `test_xxx.py`, you can run the tests using:

    $ cd src/binding/petsc4py
    $ python test/runtests.py -k test_xxx

If instead you are modifying an existing `test_xxx.py`, you can test your additions by using the fully qualified name of the Python class or method you are modifying, e.g.:

    $ python test/runtests.py -k test_xxx.class_name.method_name

All new code must include documentation in accordance with the documentation standard. To check for compliance, run:

    $ make html SPHINXOPTS='-W' -C src/binding/petsc4py/docs/source

Warning

The docstrings must not cause Sphinx warnings.