Merge branch 'at/rebase-fork-point-regression-fix'

The "--fork-point" mode of "git rebase" regressed when the command
was rewritten in C back in 2.20 era, which has been corrected.

* at/rebase-fork-point-regression-fix:
  rebase: --fork-point regression fix

1 files changed, 13 insertions, 2 deletions

diff --git a/commit.c b/commit.c
index 534e14f22a..c7099daeac 100644
--- a/commit.c
+++ b/commit.c
@@ -927,12 +927,22 @@ struct commit *get_fork_point(const char *refname, struct commit *commit)
 	struct commit_list *bases;
 	int i;
 	struct commit *ret = NULL;
+	char *full_refname;
+
+	switch (dwim_ref(refname, strlen(refname), &oid, &full_refname)) {
+	case 0:
+		die("No such ref: '%s'", refname);
+	case 1:
+		break; /* good */
+	default:
+		die("Ambiguous refname: '%s'", refname);
+	}
 
 	memset(&revs, 0, sizeof(revs));
 	revs.initial = 1;
-	for_each_reflog_ent(refname, collect_one_reflog_ent, &revs);
+	for_each_reflog_ent(full_refname, collect_one_reflog_ent, &revs);
 
-	if (!revs.nr && !get_oid(refname, &oid))
+	if (!revs.nr)
 		add_one_commit(&oid, &revs);
 
 	for (i = 0; i < revs.nr; i++)
@@ -958,6 +968,7 @@ struct commit *get_fork_point(const char *refname, struct commit *commit)
 
 cleanup_return:
 	free_commit_list(bases);
+	free(full_refname);
 	return ret;
 }