update-ref: add support for 'symref-delete' command

Add a new command 'symref-delete' to allow deletions of symbolic refs in
a transaction via the '--stdin' mode of the 'git-update-ref' command.
The 'symref-delete' command can, when given an <old-target>, delete the
provided <ref> only when it points to <old-target>.

This command is only compatible with the 'no-deref' mode because we
optionally want to check the 'old_target' of the ref being deleted.
De-referencing a symbolic ref would provide a regular ref and we already
have the 'delete' command for regular refs.

While users can also use 'git symbolic-ref -d' to delete symbolic refs,
the 'symref-delete' command in 'git-update-ref' allows users to do so
within a transaction, which promises atomicity of the operation and can
be batched with other commands.

When no 'old_target' is provided it can also delete regular refs,
similar to how the 'delete' command can delete symrefs when no 'old_oid'
is provided.

Helped-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Karthik Nayak
2024-06-07 15:33:01 +02:00
committed by Junio C Hamano
parent 1451ac734f
commit 2343720967
8 changed files with 140 additions and 10 deletions

View File

@ -1382,8 +1382,8 @@ static int prune_refs(struct display_state *display_state,
if (!dry_run) {
if (transaction) {
for (ref = stale_refs; ref; ref = ref->next) {
result = ref_transaction_delete(transaction, ref->name, NULL, 0,
"fetch: prune", &err);
result = ref_transaction_delete(transaction, ref->name, NULL,
NULL, 0, "fetch: prune", &err);
if (result)
goto cleanup;
}