How to contribute

Contributions are welcome, and they are greatly appreciated! Every little bit helps, and credit will always be given.

• You can report bugs at zfit/zfit#issues.

• You can send feedback by filing an issue at zfit/zfit#issues or, for more informal discussions, you can also join our Gitter channel.

Get Started!

Ready to contribute? Here’s how to set up zfit for local development.

1. Fork the zfit repo on GitHub.

2. Clone your fork locally:

git clone git@github.com:your_name_here/zfit.git

3. Install your local copy into a conda/mamba or other virtual environment. For example with conda, do

conda create -n zfit311 python=3.11
conda activate zfit311
pip install -e .[alldev]  # . is the folder where setup.py is

Further, you can install pre-commit locally to run the checks before you commit:

pip install pre-commit
pre-commit install  # this will execute pre-commit checks before every commit

4. Create a branch for local development

 git checkout -b name-of-your-bugfix-or-feature

Now you can make your changes locally.

5. When you’re done making changes, check that your changes pass the tests (this can take a while ~30 mins). You can run the tests in parallel by installing pytest-xdist and running pytest -n NUM where NUM is the number of cores

pytest  # in the root folder of the repository where tests folder is

(Some tests have a @flaky decorator, which means that they might fail sometimes. If you see a flaky test failing, inspect it, but most likely it’s not a problem with your changes. Rerunning the specific test usually solves the problem.)

Some elements, like objects that can be dumped to HS3, new PDFs etc, have a truth. This is a reference file and test that check against such a file are therefore expected to fail (as the truth file doesn’t exist yet). To create/regenerate a truth file, run the specific test that uses a truth file with the option --recreate-truth after you verified that the output is actually correct.

For example, to run the test test_dumpload_hs3_pdf in file tests/serialize/test_hs3_user.py, run

pytest tests/serialize/test_hs3_user.py::test_dumpload_hs3_pdf -- --recreate-truth

6. Commit your changes and push your branch to GitHub

git add .
git commit -m "Your detailed description of your changes."
git push origin name-of-your-bugfix-or-feature

7. Submit a pull request through the GitHub website. The test suite is going to run again, testing all the necessary Python versions.

Pull Request Guidelines

Before you submit a pull request, check that it meets these guidelines:

1. The pull request should include tests.

2. If the pull request adds functionality, the docs may need to be updated. Put your new functionality into a function with a docstring (and add the necessary explanations in the corresponding rst file in the docs). If any math is involved, please document the exact formulae implemented in the docstring/docs. New elements, such as a new PDF, should for example be added to the docs/user_api/pdf/suitable_file.rst.