A tree-sitter grammar for Pkl.

# install dependencies
$ npm install

# build parser
$ npm run build

# parse some code
$ ./node_modules/.bin/tree-sitter parse test.pkl

Tests

Tree sitter comes with its own test framework. Files in corpus/ describe one test each. All tests in corpus/ are performed by the command

$ tree-sitter test

The script src/synctests.ts creates corpus/ test files from tests in pkl's LanguageSnippetTests. The script assumes that ../pkl is a checked out pkl repository (and that the tests are under pkl-core/src/test/files/LanguageSnippetFiles/input). A pre-condition of the script is that tree-sitter test currently passes. If broken tests need replacing, the broken tests must first be deleted.

It can be executed by running

$ npm run synctests

Upgrading tree-sitter

Upgrading tree-sitter involves upgrading the NPM package.

1. Run npm update tree-sitter to install the newer version of tree-sitter.
2. Commit to main, and push.

Releasing

1. Run the build & test to make sure everything is up-to-date and passes (check 0 diff).
2. Create a Prepare 1.2.3 release (with appropriate version number) commit where

• Versions are bumped in package.json, Cargo.toml
• Lockfiles are updated (npm install, cargo check)
• You have checked the previous release PR for any changes in process not described in this README.adoc; if any
  • Adopt the changes accordingly
  • Update this description to capture the changed process

3. Merge into main & push
4. Check that CI release succeeded (release pipeline)
5. Check the publication is reachable, on NPM

Resources

• Tree-sitter docs
• Guide to your first Tree-sitter grammar