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.

1 files changed, 1 insertions, 9 deletions

diff --git a/flake.nix b/flake.nix
index e1cd5036..38ba9fd0 100644
--- a/flake.nix
+++ b/flake.nix
@@ -12,17 +12,9 @@
       inputs.nixpkgs.follows = "nixpkgs";
       inputs.rustOverlay.follows = "rust-overlay";
     };
-    # NOTE: the flake looks like it is hanging when it pulls this input because
-    # the submodules take a long time to clone. This will be fixed in #1659.
-    helix = {
-      url = "https://github.com/helix-editor/helix.git";
-      type = "git";
-      submodules = true;
-      flake = false;
-    };
   };
 
-  outputs = inputs@{ nixCargoIntegration, helix, ... }:
+  outputs = inputs@{ nixCargoIntegration, ... }:
     nixCargoIntegration.lib.makeOutputs {
       root = ./.;
       renameOutputs = { "helix-term" = "helix"; };