From: Michael Lohmann <mi.al.lohmann@gmail.com>
Date: Wed, 28 Feb 2024 13:54:53 +0000 (-0500)
Subject: revision: ensure MERGE_HEAD is a ref in prepare_show_merge
X-Git-Tag: v2.45.0-rc0~129^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f476143ee6c8a58f41c569e4a637bc441b1e6f4a;p=thirdparty%2Fgit.git

revision: ensure MERGE_HEAD is a ref in prepare_show_merge

This is done to

 (1) ensure MERGE_HEAD is a ref,
 (2) obtain the oid without any prefixing by refs.c:repo_dwim_ref()
 (3) error out when MERGE_HEAD is a symref.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Lohmann <mi.al.lohmann@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

diff --git a/revision.c b/revision.c
index 2424c9bd67..df775f74d0 100644
--- a/revision.c
+++ b/revision.c
@@ -1973,8 +1973,12 @@ static void prepare_show_merge(struct rev_info *revs)
 	if (repo_get_oid(the_repository, "HEAD", &oid))
 		die("--merge without HEAD?");
 	head = lookup_commit_or_die(&oid, "HEAD");
-	if (repo_get_oid(the_repository, "MERGE_HEAD", &oid))
+	if (read_ref_full("MERGE_HEAD",
+			RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+			&oid, NULL))
 		die("--merge without MERGE_HEAD?");
+	if (is_null_oid(&oid))
+		die(_("MERGE_HEAD exists but is a symbolic ref"));
 	other = lookup_commit_or_die(&oid, "MERGE_HEAD");
 	add_pending_object(revs, &head->object, "HEAD");
 	add_pending_object(revs, &other->object, "MERGE_HEAD");