tree-sitter-grammars: pin rev for unstable grammars

[andresilva]

Things done

Grammars pod and quint use github:owner/repo/release as their URL, which causes parseUrl to pass the branch name release directly as rev to fetchFromGitHub. This works on first fetch but produces hash mismatches once the branch advances.

This adds a rev attribute to grammar sources that takes priority over the ref parsed from the URL, allowing the branch name to remain in the URL for nix-update compatibility while pinning the actual commit. An assertion ensures unstable grammars always resolve to a commit hash.

The update script also passed --version branch for all unstable grammars, which tracks the default branch. Grammars with an explicit branch in their URL now pass --version branch=REF instead.

• Built on platform:
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• Tested, as applicable:
  • NixOS tests in nixos/tests.
  • Package tests at passthru.tests.
  • Tests in lib/tests or pkgs/test for functions and "core" functionality.
• Ran nixpkgs-review on this PR. See nixpkgs-review usage.
• Tested basic functionality of all binary files, usually in ./result/bin/.
• Nixpkgs Release Notes
  • Package update: when the change is major or breaking.
• NixOS Release Notes
  • Module addition: when adding a new NixOS module.
  • Module update: when the change is significant.
• Fits CONTRIBUTING.md, pkgs/README.md, maintainers/README.md and other READMEs.

[andresilva]

nixpkgs-review result

Generated using nixpkgs-review.

Command: nixpkgs-review pr 491704
Commit: bfab3b5870fe98129bd1d2d1d28fb4ca4b7a707a

---

x86_64-linux

✅ 6 packages built:

• diffsitter
• python313Packages.tree-sitter-grammars.tree-sitter-quint
• python313Packages.tree-sitter-grammars.tree-sitter-quint.dist
• python314Packages.tree-sitter-grammars.tree-sitter-quint
• python314Packages.tree-sitter-grammars.tree-sitter-quint.dist
• tree-sitter-grammars.tree-sitter-quint

[teto]

dont we want to avoid this scenario source.ref ? if it's for the assert later, unstable version requires a pinned commit hash as rev, got '${rev or source.ref}'" would be cleaner.

[andresilva]

I updated it so that unstable grammars must have a rev attribute, rather than parsing it from the URL. I think that's simpler.

[aciceri]

Aside form the comment by @teto the idea looks good to me, thank you for working on this that that fast.

I believe we also want to make @kimburgess aware of this issue.

[andresilva]

nixpkgs-review result

Generated using nixpkgs-review.

Command: nixpkgs-review pr 491704
Commit: ebfb1d12d482441c97c92a4b8e82d5c4cdd26e24

---

x86_64-linux

✅ 6 packages built:

• diffsitter
• python313Packages.tree-sitter-grammars.tree-sitter-quint
• python313Packages.tree-sitter-grammars.tree-sitter-quint.dist
• python314Packages.tree-sitter-grammars.tree-sitter-quint
• python314Packages.tree-sitter-grammars.tree-sitter-quint.dist
• tree-sitter-grammars.tree-sitter-quint