tree-sitter-haskell-contrib

Tree-sitter grammars for Haskell-ecosystem file formats.

• tree-sitter-cabal: .cabal package description files
• tree-sitter-cabal-project: cabal.project and *.project workspace files
• tree-sitter-ghc-core: GHC Core dumps (-ddump-simpl and the other Core passes)
• tree-sitter-ghc-core-explain: GHC simplifier-explanation logs (-ddump-rule-firings, -ddump-inlinings)
• tree-sitter-ghc-stg: GHC STG dumps (-ddump-stg-final and the other STG passes)
• tree-sitter-ghc-cmm: GHC Cmm dumps (-ddump-cmm and the pipeline-stage passes)
• tree-sitter-ghc-dump: container grammar that injects the per-IL grammars into multi-section dump files

The .cabal grammar was initially forked from magus/tree-sitter-cabal.

Setup

nix develop   # enter dev shell (provides tree-sitter, just, etc.)

Commands

All commands run across every grammar via the top-level justfile.

Command	Description
just	Run every grammar's full suite (default)
just test	Per grammar: query compile, parse-corpus, inline tests, and the GHC dump matrix across every flake.nix ghcVersions GHC. Runs all suites to completion, then fails if any failed (heavy)
just test --fast	Same, but the GHC dump matrix uses only the default nixpkgs GHC (quick)
just build	Generate each parser and build its shared library
just check	Validate every grammar without building
just fmt	Format grammar files and the flake (prettier and nixfmt)
just gen-corpus	Build and parse the GHC dump-flag matrix as a TAP suite for the default GHC; set GEN_GHC=all for every ghcVersions GHC (needs a GHC compiler)
just clean	Remove build artifacts

Per-grammar commands are available as just <name>::<cmd>, where <name> is one of cabal, cabal-project, ghc-core, ghc-stg, ghc-cmm, ghc-dump.

Testing

The cabal grammars parse a corpus drawn from the cabal and haskell-language-server source trees.

The GHC grammars parse a harvested corpus of real dumps from the GHC test suite. On top of that, gen-corpus compiles a handful of fixtures with GHC across a matrix of dump and display flags.

• just test runs the matrix once per version listed in flake.nix ghcVersions, validating against several compilers.

• just test --fast and the CI pull-request gate restrict it to the one GHC in the pinned nixpkgs.

References

• Tree-sitter: Creating parsers
• Cabal: .cabal file reference
• Cabal: cabal.project reference
• GHC: dumping intermediate output

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Disclaimer: co-produced with a coding agent.