See README. Leaving Gleam's own CONTRIBUTING.md
below for reference.
Thanks for contributing to Gleam!
Before continuing please read our code of conduct which all contributors are expected to adhere to.
If you have found a bug in Gleam please check to see if there is an open ticket for this problem on our GitHub issue tracker. If you cannot find an existing ticket for the bug please open a new one.
A bug may be a technical problem such as a compiler crash or an incorrect return value from a library function, or a user experience issue such as unclear or absent documentation. If you are unsure if your problem is a bug please open a ticket and we will work it out together.
Before working on code it is suggested that you read the docs/compiler/README.md file. It outlines fundamental components and design of this project.
Code changes to Gleam are welcomed via the process below.
- Find or open a GitHub issue relevant to the change you wish to make and comment saying that you wish to work on this issue. If the change introduces new functionality or behaviour this would be a good time to discuss the details of the change to ensure we are in agreement as to how the new functionality should work.
- Open a GitHub pull request with your changes and ensure the tests and build pass on CI.
- A Gleam team member will review the changes and may provide feedback to work on. Depending on the change there may be multiple rounds of feedback.
- Once the changes have been approved the code will be rebased into the
main
branch.
To run the compiler tests. This will require a recent stable version of Rust to be installed.
If you are using the Nix package manager, there's a gleam-nix flake you can use for running any Gleam version or quickly obtaining a development environment for Gleam.
cargo test
# Or if you have watchexec installed you can run them automatically
# when files change
make test-watch
To run the language integration tests. This will require a recent stable version of Rust, Erlang, and NodeJS to be installed.
make language-test
If you don't have Rust or Cargo installed you can run the above command in a docker sandbox. Run the command below from this directory.
docker run -v $(pwd):/opt/app -it -w /opt/app rust:latest bash
Here are some tips and guidelines for writing Rust code in the Gleam compiler:
The GLEAM_LOG
environment variable can be used to cause the compiler to
print more information for debugging and introspection. i.e.
GLEAM_LOG=trace
.
Your PR may fail on CI due to clippy errors. Clippy can be run locally like so:
cargo clean -p gleam
cargo clippy
If you have lint errors on CI but not locally upgrade your Rust version to the latest stable.
rustup upgrade stable
The compiler uses a Cap'n Proto schema to serialize/deserialize module information.
Occasionally, the schema needs to change. After modifying compiler-core/schema.capnp
you need to to re-generate compiler-core/generated/schema_capnp.rs
. To do that,
install Cap'n Proto and un-comment appropriate lines
in compiler-core/build.rs
. Then you should be able to re-generate that file with:
cd compiler-core
cargo build