refs: don't invoke reference-transaction hook for reflogs

The reference-transaction hook is invoked whenever there is a reference
update being performed. For each state of the transaction, we iterate
over the updates present and pass this information to the hook.

The `ref_update` structure is used to hold these updates within a
`transaction`. We use the same structure for holding reflog updates too.
Which means that the reference transaction hook is also obtaining
information about a reflog update. This is a bug, since:

  - The hook is designed to work with reference updates and reflogs
  updates are different.
  - The hook doesn't have the required information to distinguish
  reference updates from reflog updates.

This is particularly evident when the default branch (pointed by HEAD)
is updated, we see that the hook also receives information about HEAD
being changed. In reality, we only add a reflog update for HEAD, while
HEAD's values remains the same.

Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/refs.c b/refs.c
index 5f729ed4124f7fe8fa9df7fd1f1ce951abefc585..7866cd7378da95b3cdd508500633958802d166d0 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -2185,6 +2185,9 @@ static int run_transaction_hook(struct ref_transaction *transaction,
        for (i = 0; i < transaction->nr; i++) {
                struct ref_update *update = transaction->updates[i];
 
+               if (update->flags & REF_LOG_ONLY)
+                       continue;
+
                strbuf_reset(&buf);
 
                if (!(update->flags & REF_HAVE_OLD))

diff --git a/t/t1416-ref-transaction-hooks.sh b/t/t1416-ref-transaction-hooks.sh
index 5a812ca3c0b5d3f7de60dc999de6aafaf1f384a6..262efec60e85b7e00def18cce15d5ce15897836d 100755 (executable)
--- a/t/t1416-ref-transaction-hooks.sh
+++ b/t/t1416-ref-transaction-hooks.sh
@@ -53,7 +53,6 @@ test_expect_success 'hook gets all queued updates in prepared state' '
                fi
        EOF
        cat >expect <<-EOF &&
-               $ZERO_OID $POST_OID HEAD
                $ZERO_OID $POST_OID refs/heads/main
        EOF
        git update-ref HEAD POST <<-EOF &&
@@ -76,7 +75,6 @@ test_expect_success 'hook gets all queued updates in committed state' '
                fi
        EOF
        cat >expect <<-EOF &&
-               $ZERO_OID $POST_OID HEAD
                $ZERO_OID $POST_OID refs/heads/main
        EOF
        git update-ref HEAD POST &&