Contributing to Spire

This document is a guide to how to get started contributing to Spire.

Writing guides or documentation

Often the biggest issue facing open-source projects is a lack of good documentation, and Spire is no exception here. If you have ideas for specific pieces of documentation which are absent, feel free to open a specific issue for that.

We also gladly accept patches for documentation. Anything from fixing a typo to writing a full tutorial is a great way to help the project.

The documentation lives in the docs/src/main/mdoc directory in the repository. To preview the website locally:

1. Install Jekyll v4.
2. Run sbt docs/makeMicrosite. Change directory to docs/target/site and run jekyll serve -b /spire.
3. Preview website at http://localhost:4000/spire.

Reporting bugs, issues, or unexpected behavior

If you encounter anything that is broken, confusing, or could be better, you should open an issue. You don't have to know why the error is occurring, or even that an error happens at all.

If you are trying to do something with Spire, and are having a hard time, it could be any of the following issues:

• an actual bug or error

• an omission or problem with the API

• a confusing edge case

• a documentation problem

Feel free to open a bug before you're sure which of these is happening. You can also ask questions on the #spire channel on the Typelevel Discord to get other people's opinions.

Creating or improving tests

Spire uses munit and ScalaCheck to test our code. The tests fulfill a number of important functions:

• ensure our algorithms return correct results

• check the visibility of our type class instances

• confirm that the API works as we expect

• test edge cases which might otherwise be missed

If you find a bug you are also encouraged to submit a test case (the code you tried that failed). Adding these failing cases to Spire's tests provides a good way to ensure the bug is really fixed, and is also a good opportunity to start contributing.

ALso, when you notice places that lack tests (or where the tests are sparse, incomplete, or just ugly) feel free to submit a pull request with improvements!

Submitting patches or code

Spire is on Github to make it easy to fork the code and change it. There are very few requirements but here are some suggestions for what makes a good pull request.

If you're writing a small amount of code to fix a bug, feel free to just open a pull request immediately. You can even attach some code snippets to the issue if that's easier.

For adding new code to Spire, it's often smart to create a topic branch that can be used to collaborate on the design. Features that require a lot of code, or which represent a big change to Spire, tend not to get merged to main as quickly. For this kind of work, you should submit a pull request from your branch, but we will probably leave the PR open for awhile while commenting on it.

You can always message the #spire channel on the Typelevel Discord to get a second opinion on your idea or design.

Ask questions and make suggestions

Spire strives to be an excellent part of the Scala ecosystem. We welcome your questions about how Spire works now, and your ideas for how to make it even better!