chore: improve actions-runner-controller maintenance path

testing/git.go

@@ -33,6 +33,10 @@ func (g *GitRepo) Sync(ctx context.Context) error {
 		return errors.New("missing git dir")
 	}
 
+	if g.Branch == "" {
+		return errors.New("missing git branch")
+	}
+
 	dir, err := filepath.Abs(g.Dir)
 	if err != nil {
 		return fmt.Errorf("error getting abs path for %q: %w", g.Dir, err)

testing/git_test.go

@@ -0,0 +1,45 @@
+package testing
+
+import (
+	"context"
+	"errors"
+	"testing"
+)
+
+func TestGitRepoSyncValidation(t *testing.T) {
+	ctx := context.Background()
+
+	tests := []struct {
+		name string
+		repo GitRepo
+		want error
+	}{
+		{
+			name: "missing name",
+			repo: GitRepo{Dir: "/tmp/repo", Branch: "main"},
+			want: errors.New("missing git repo name"),
+		},
+		{
+			name: "missing dir",
+			repo: GitRepo{Name: "owner/repo", Branch: "main"},
+			want: errors.New("missing git dir"),
+		},
+		{
+			name: "missing branch",
+			repo: GitRepo{Name: "owner/repo", Dir: "/tmp/repo"},
+			want: errors.New("missing git branch"),
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := tt.repo.Sync(ctx)
+			if err == nil {
+				t.Fatalf("expected error %q, got nil", tt.want)
+			}
+			if err.Error() != tt.want.Error() {
+				t.Errorf("expected error %q, got %q", tt.want, err)
+			}
+		})
+	}
+}