Tree sitter grammar for CFEngine policy language

This tree-sitter grammar parses CFEngine policy language and turns it into an abstract syntax tree. It is used to provide syntax highlighting in the Zed editor, via this extension:

https://github.com/olehermanse/zed-cfengine

The grammar currently supports all major features of the language, including:

Bundle blocks
Body blocks
Promise type definition blocks
Promise types, class guards, promises, stakeholders (promisees)
Macros
Function calls
Lists, strings, expansions (with $() and @())

Todos

Using the grammar for linting / syntax checking (language server)
Highlighting inside strings and comments
Recognizing when there is JSON inside policy
Class guards which are quoted strings
Using the grammar for code indentation
Using the grammar for extensions to other editors

Before contributing for the first time, it's recommended to go through the tree-sitter tutorial for getting familiar with how everything works:

https://tree-sitter.github.io/tree-sitter/creating-parsers

Inspired by Lars Erik Wik's initial implementation available here:

https://github.com/larsewi/tree-sitter-cfengine

Run containerized tests locally:

docker build --tag tree-sitter-cfengine .

Making changes

After making changes to grammar.js, run the the commands below to generate, build, and test:

tree-sitter generate && tree-sitter build && tree-sitter test

In tree-sitter projects, it is normal to commit the files generated / edited by the tree-sitter tooling. Once it is working and tests are passing, commit the changes (including src/ folder with generated files).

Updating dependencies

npm update --save && cargo update && uv sync --upgrade

Creating a new release

Creating a release in GitHub will not work. To create a new release, you need to make a commit and tag locally, and push it. First ensure you have a clean git repo without any uncommitted changes. Then, run the following commands:

export PUBLISH_VERSION="1.2.3"
tree-sitter version $PUBLISH_VERSION
tree-sitter generate && tree-sitter build && tree-sitter test
npm update --save && cargo update && uv sync --upgrade
tree-sitter generate && tree-sitter build && tree-sitter test
git add -A && git commit -S -s -m "Bump to version $PUBLISH_VERSION" && git tag -s -a $PUBLISH_VERSION -m $PUBLISH_VERSION
git push --tags