Updater: dispatch to update-ref create/delete/updateavar/use-update-ref-delete-and-create

Instead of always issuing "update" commands, use the "create" and
"delete" verbs too.

This doesn't make any difference in the result as git does the same
dispatching internally, but makes things a bit more obvious if you're
tracing the output.

3 files changed, 20 insertions, 1 deletions

diff --git a/changelogs/unreleased/avar-use-update-ref-delete-and-create.yml b/changelogs/unreleased/avar-use-update-ref-delete-and-create.yml
new file mode 100644
index 000000000..240c41335
--- /dev/null
+++ b/changelogs/unreleased/avar-use-update-ref-delete-and-create.yml
@@ -0,0 +1,5 @@
+---
+title: 'Cleaner & DeleteRefs: use safer ''update-ref delete'' with <oldvalue> argument'
+merge_request: 2929
+author:
+type: fixed
diff --git a/internal/git/updateref/updateref.go b/internal/git/updateref/updateref.go
index c141b4eac..f82098626 100644
--- a/internal/git/updateref/updateref.go
+++ b/internal/git/updateref/updateref.go
@@ -65,6 +65,20 @@ func New(ctx context.Context, repo repository.GitRepo, opts ...UpdaterOpt) (*Upd
 	return &Updater{repo: repo, cmd: cmd}, nil
 }
 
+// CreateUpdateDelete dispatches to Create()/Update()/Delete() as needed
+//
+// The underlying "update-ref" does the same dispatching depending on
+// what it get passed.
+func (u *Updater) CreateUpdateDelete(ref, newvalue, oldvalue string) error {
+	if newvalue == git.NullSHA {
+		return u.Delete(ref, oldvalue)
+	} else if oldvalue == git.NullSHA {
+		return u.Create(ref, newvalue)
+	} else {
+		return u.Update(ref, newvalue, oldvalue)
+	}
+}
+
 // Create commands the reference to be created with the sha specified in value
 func (u *Updater) Create(ref, value string) error {
 	_, err := fmt.Fprintf(u.cmd, "create %s\x00%s\x00", ref, value)
diff --git a/internal/gitaly/service/operations/update_with_hooks.go b/internal/gitaly/service/operations/update_with_hooks.go
index ba90634bc..937b00f40 100644
--- a/internal/gitaly/service/operations/update_with_hooks.go
+++ b/internal/gitaly/service/operations/update_with_hooks.go
@@ -80,7 +80,7 @@ func (s *Server) updateReferenceWithHooks(ctx context.Context, repo *gitalypb.Re
 		return err
 	}
 
-	if err := updater.Update(reference, newrev, oldrev); err != nil {
+	if err := updater.CreateUpdateDelete(reference, newrev, oldrev); err != nil {
 		return err
 	}