From e01c53551db82146b59415498fc8f588f237b22c Mon Sep 17 00:00:00 2001
From: Michael Davis
Date: Wed, 9 Mar 2022 08:34:52 -0600
Subject: flake: use builtins.fetchTree to shallow-clone grammar repos

Here we perform a shallow fetch using builtins.fetchTree. In order
to make this work, we need to specify the `ref' for any repository
that doesn't have `master' as its default branch (I'm not sure why
this limitation exists since we don't need this when performing
the shallow fetch in `--grammar build')

This `ref' field is ignored by helix, so I have left it undocumented
for now, but I could be open to documenting it.
---
 grammars.nix | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

(limited to 'grammars.nix')

diff --git a/grammars.nix b/grammars.nix
index 6dbc05c8..bd2c95cc 100644
--- a/grammars.nix
+++ b/grammars.nix
@@ -13,10 +13,12 @@ let
   gitGrammars = builtins.filter isGitGrammar languagesConfig.grammar;
   buildGrammar = grammar:
     let
-      source = builtins.fetchGit {
+      source = builtins.fetchTree {
+        type = "git";
         url = grammar.source.git;
         rev = grammar.source.rev;
-        allRefs = true;
+        ref = grammar.source.ref or "HEAD";
+        shallow = true;
       };
     in stdenv.mkDerivation rec {
       # see https://github.com/NixOS/nixpkgs/blob/fbdd1a7c0bc29af5325e0d7dd70e804a972eb465/pkgs/development/tools/parsing/tree-sitter/grammar.nix
-- 
cgit v1.2.3-70-g09d2