feat: add an option to disable gc root creation

Mostly for testing.
cachix · Aug 24, 2024 · 3ca51c2 · 3ca51c2
1 parent 6736cfd
commit 3ca51c2
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Showing 2 changed files with 15 additions and 3 deletions.
diff --git a/modules/pre-commit.nix b/modules/pre-commit.nix
@@ -281,6 +281,14 @@ in
           internal = true;
         };
 
+      addGcRoot = mkOption {
+        type = types.bool;
+        default = true;
+        description = ''
+          Whether to add the generated pre-commit-config.json to the garbage collector roots.
+        '';
+      };
+
       assertions = lib.mkOption {
         type = types.listOf types.unspecified;
         internal = true;
@@ -351,7 +359,11 @@ in
                 echo 1>&2 "    2. remove .pre-commit-config.yaml"
                 echo 1>&2 "    3. add .pre-commit-config.yaml to .gitignore"
               else
-                nix-store --add-root "''${GIT_WC}/.pre-commit-config.yaml" --realise ${configFile}
+                if [ $]
+                  nix-store --add-root "''${GIT_WC}/.pre-commit-config.yaml" --realise ${configFile}
+                else
+                  ln -fs ${configFile} "''${GIT_WC}/.pre-commit-config.yaml"
+                fi
                 # Remove any previously installed hooks (since pre-commit itself has no convergent design)
                 hooks="${concatStringsSep " " (remove "manual" supportedHooksLib.supportedHooks )}"
                 for hook in $hooks; do

diff --git a/nix/installation-test.nix b/nix/installation-test.nix
@@ -61,7 +61,7 @@ let
 
   executeTest = lib.mapAttrsToList
     (name: test:
-      let runDerivation = run ({ src = null; } // test.conf);
+      let runDerivation = run ({ src = null; settings.addGcRoot = false; } // test.conf);
       in ''
         rm -f ~/.git/hooks/*
         ${runDerivation.shellHook}
@@ -74,7 +74,7 @@ let
       '')
     tests;
 in
-runCommand "installation-test" { nativeBuildInputs = [ git perl coreutils mktemp nix ]; } ''
+runCommand "installation-test" { nativeBuildInputs = [ git perl coreutils mktemp ]; } ''
   set -eoux
 
   HOME=$(mktemp -d)