This outlines how to propose a change to loo and is based on similar instructions for tidyverse packages, including the contributing guidelines generated by usethis::use_tidy_contributing().

Fixing typos

You can fix typos, spelling mistakes, or grammatical errors in the documentation directly using the GitHub web interface, as long as the changes are made in the source file. This generally means you’ll need to edit roxygen2 comments in an .R, not a .Rd file. You can find the .R file that generates the .Rd by reading the comment in the first line.

Bigger changes

If you want to make a bigger change, it’s a good idea to first file an issue and make sure someone from the team agrees that it’s needed. If you’ve found a bug, please file an issue that illustrates the bug with a minimal reproducible example (see e.g. the tidyverse reprex instructions). The tidyverse guide on how to create a great issue has more advice.

Pull request process

If you are new to creating pull requests here are some tips. Using the functions from the usethis package is not required but can be helpful if this process is new to you.

  • Fork the package and clone onto your computer. If you haven’t done this before, we recommend using usethis::create_from_github("stan-dev/loo", fork = TRUE).

  • Install all development dependencies with devtools::install_dev_deps(), and then make sure the package passes R CMD check by running devtools::check(). If R CMD check doesn’t pass cleanly, it’s a good idea to ask for help before continuing.

  • Create a Git branch for your pull request (PR). We recommend using usethis::pr_init("brief-description-of-change").

  • Make your changes, commit to git, and then create a PR by running usethis::pr_push(), and following the prompts in your browser. The title of your PR should briefly describe the change. The body of your PR should contain Fixes #issue-number.

  • For user-facing changes, add a bullet to the top of (i.e. just below the first header). Follow the style already used in

Code style

  • New code should attempt to follow the style used in the package. When in doubt follow the tidyverse style guide.

  • We use roxygen2, with Markdown syntax, for documentation.

  • We use testthat for unit tests. Contributions with test cases included are easier to accept.

Code of Conduct

Please note that the loo project follows the Stan project’s Code of Conduct. By contributing to this project you agree to abide by its terms.