updateRef(): make into a test helper function

It's only needed for testing.

Author: mhagger

git/git.go

@@ -522,17 +522,6 @@ func (repo *Repository) CreateObject(t ObjectType, writer func(io.Writer) error)
 	return NewOID(string(bytes.TrimSpace(output)))
 }
 
-func (repo *Repository) UpdateRef(refname string, oid OID) error {
-	var cmd *exec.Cmd
-
-	if oid == NullOID {
-		cmd = repo.gitCommand("update-ref", "-d", refname)
-	} else {
-		cmd = repo.gitCommand("update-ref", refname, oid.String())
-	}
-	return cmd.Run()
-}
-
 // Next returns the next object, or EOF when done.
 func (l *ObjectIter) Next() (OID, ObjectType, counts.Count32, error) {
 	line, err := l.f.ReadString('\n')

git_sizer_test.go

@@ -33,6 +33,19 @@ func gitCommand(t *testing.T, repoPath string, args ...string) *exec.Cmd {
 	return cmd
 }
 
+func updateRef(t *testing.T, repoPath string, refname string, oid git.OID) error {
+	t.Helper()
+
+	var cmd *exec.Cmd
+
+	if oid == git.NullOID {
+		cmd = gitCommand(t, repoPath, "update-ref", "-d", refname)
+	} else {
+		cmd = gitCommand(t, repoPath, "update-ref", refname, oid.String())
+	}
+	return cmd.Run()
+}
+
 func addFile(t *testing.T, repoPath string, repo *git.Repository, relativePath, contents string) {
 	dirPath := filepath.Dir(relativePath)
 	if dirPath != "." {
@@ -119,7 +132,7 @@ func newGitBomb(
 	})
 	require.NoError(t, err)
 
-	err = repo.UpdateRef("refs/heads/master", oid)
+	err = updateRef(t, repo.Path(), "refs/heads/master", oid)
 	require.NoError(t, err)
 
 	return repo