Merge pull request 'fix: use custom git config in impure-checks to avoid system dependency' (#4037) from fix-impure-checks-git-config into main

Reviewed-on: https://git.clan.lol/clan/clan-core/pulls/4037

checks/impure/flake-module.nix

@@ -28,6 +28,12 @@
         ROOT=$(git rev-parse --show-toplevel)
         cd "$ROOT/pkgs/clan-cli"
 
+        # Set up custom git configuration for tests
+        export GIT_CONFIG_GLOBAL=$(mktemp)
+        git config --file "$GIT_CONFIG_GLOBAL" user.name "Test User"
+        git config --file "$GIT_CONFIG_GLOBAL" user.email "test@example.com"
+        export GIT_CONFIG_SYSTEM=/dev/null
+
         # this disables dynamic dependency loading in clan-cli
         export CLAN_NO_DYNAMIC_DEPS=1
 
@@ -37,6 +43,9 @@
         jobs="$((jobs > 13 ? 13 : jobs))"
 
         nix develop "$ROOT#clan-cli" -c bash -c "TMPDIR=/tmp python -m pytest -n $jobs -m impure ./clan_cli $@"
+
+        # Clean up temporary git config
+        rm -f "$GIT_CONFIG_GLOBAL"
       '';
     };
 }