backup: Set HEAD from bundle filesupdate-head-14-5

Previously backup relied on git-clone setting HEAD from bundle files but
now that we apply a series of bundles, the bundles are applied using
git-fetch instead. This means we need to apply our own HEAD setting
logic based off of the bundle.

ChecksumTestRepo was incorrectly calculating repository checksums
without HEAD.

Changelog: fixed

3 files changed, 6 insertions, 2 deletions

diff --git a/internal/backup/backup.go b/internal/backup/backup.go
index b26e47466..f596b216d 100644
--- a/internal/backup/backup.go
+++ b/internal/backup/backup.go
@@ -395,7 +395,7 @@ func (mgr *Manager) restoreBundle(ctx context.Context, path string, server stora
 	if err != nil {
 		return fmt.Errorf("restore bundle: %q: %w", path, err)
 	}
-	request := &gitalypb.FetchBundleRequest{Repository: repo}
+	request := &gitalypb.FetchBundleRequest{Repository: repo, UpdateHead: true}
 	bundle := streamio.NewWriter(func(p []byte) error {
 		request.Data = p
 		if err := stream.Send(request); err != nil {
diff --git a/internal/backup/backup_test.go b/internal/backup/backup_test.go
index b7226ff93..0e3c36ecf 100644
--- a/internal/backup/backup_test.go
+++ b/internal/backup/backup_test.go
@@ -479,8 +479,10 @@ func testManagerRestore(t *testing.T, cfg config.Cfg, gitalyAddr string) {
 					gittest.WithBranch("other"),
 					gittest.WithParents(root),
 				)
+				gittest.Exec(t, cfg, "-C", expectedRepoPath, "symbolic-ref", "HEAD", "refs/heads/master")
 				bundlePath1 := filepath.Join(backupPath, "001.bundle")
 				gittest.Exec(t, cfg, "-C", expectedRepoPath, "bundle", "create", bundlePath1,
+					"HEAD",
 					"refs/heads/master",
 					"refs/heads/other",
 				)
@@ -491,6 +493,7 @@ func testManagerRestore(t *testing.T, cfg config.Cfg, gitalyAddr string) {
 				)
 				bundlePath2 := filepath.Join(backupPath, "002.bundle")
 				gittest.Exec(t, cfg, "-C", expectedRepoPath, "bundle", "create", bundlePath2,
+					"HEAD",
 					"^"+master1.String(),
 					"^"+other.String(),
 					"refs/heads/master",
@@ -498,6 +501,7 @@ func testManagerRestore(t *testing.T, cfg config.Cfg, gitalyAddr string) {
 				)
 
 				checksum := new(git.Checksum)
+				checksum.Add(git.NewReference("HEAD", master2.String()))
 				checksum.Add(git.NewReference("refs/heads/master", master2.String()))
 				checksum.Add(git.NewReference("refs/heads/other", other.String()))
 
diff --git a/internal/git/gittest/repo.go b/internal/git/gittest/repo.go
index 1f060b4ca..26058d503 100644
--- a/internal/git/gittest/repo.go
+++ b/internal/git/gittest/repo.go
@@ -173,7 +173,7 @@ func BundleTestRepo(t testing.TB, cfg config.Cfg, sourceRepo, bundlePath string,
 func ChecksumTestRepo(t testing.TB, cfg config.Cfg, sourceRepo string) *git.Checksum {
 	var checksum git.Checksum
 	repoPath := testRepositoryPath(t, sourceRepo)
-	lines := bytes.Split(Exec(t, cfg, "-C", repoPath, "show-ref"), []byte("\n"))
+	lines := bytes.Split(Exec(t, cfg, "-C", repoPath, "show-ref", "--head"), []byte("\n"))
 	for _, line := range lines {
 		checksum.AddBytes(line)
 	}