nixpkgs/pkgs/development/tools/parsing/tree-sitter/grammars

Tree-sitter Grammars

Use grammar-sources.nix to define tree-sitter grammar sources.

Tree-sitter grammars follow a common form for compatibility with the tree-sitter CLI. This uniformity enables consistent packaging through shared tooling.

Adding a Grammar

To declare a new package, map the language name to a set of metadata required for the build. At a minimum, this must include the version and src.

You may use a shorthand flakeref style url and hash for concise declarations. If the hash is not yet known, use a fake hash placeholder.

{
  latex = {
    version = "0.42.0";
    url = "github:vandelay-industries/tree-sitter-latex";
    hash = "";
  };
}

This will expand to an element in pkgs.tree-sitter.grammars at build time:

{
  tree-sitter-latex = {
    language = "latex";
    version = "0.42.0";
    src = fetchFromGitHub {
      owner = "vandelay-industries";
      repo = "tree-sitter-latex";
      ref = "v0.42.0";
      hash = "";
    };
  };
}

Each entry is passed to buildGrammar, which in turn populates pkgs.tree-sitter-grammars.

Attempt to build the new grammar: nix-build -A tree-sitter-grammars.tree-sitter-latex. This will fail due to the invalid hash. Review the downloaded source, then update the source definition with the printed source hash.

Pinning Grammar Sources

To pin to a specific ref, append this to the source url to override the default version tag.

{
  latex = {
    version = "0.42.0";
    url = "github:vandelay-industries/tree-sitter-latex/ccfd77db0ed799b6c22c214fe9d2937f47bc8b34";
    hash = "";
  };
}

This may be either a commit hash or tag.

Supported sources

The url field supports the following prefixes:

• github: → uses fetchFromGitHub
• gitlab: → uses fetchFromGitLab
• sourcehut: → uses fetchFromSourcehut

To use other fetchers, specify the src attribute directly:

{
  foolang = {
    version = "0.42.0";
    src = fetchtorrent {
      config = {
        peer-limit-global = 100;
      };
      url = "magnet:?xt=urn:btih:dd8255ecdc7ca55fb0bbf81323d87062db1f6d1c";
      hash = "";
    };
  };
}

Modifying Build Behaviour

Additional attributes in the grammar definition are forwarded to buildGrammar, and then to mkDerivation. This includes build-related flags and metadata.

{
  foolang = {
    version = "1729.0.0";
    url = "sourcehut:~example/tree-sitter-foolang";
    hash = "";
    generate = true;
    meta = {
      license = lib.licenses.mit;
      maintainers = with lib.maintainers; [
        kimburgess
      ];
    };
  };
}

Updating

All grammar sources have a default update script defined. To manually trigger an update of a specific grammar definition:

nix-shell maintainers/scripts/update.nix --argstr package tree-sitter-grammars.tree-sitter-${name}

Or, to update all grammars:

nix-shell maintainers/scripts/update.nix --argstr path tree-sitter-grammars --argstr keep-going true