Merge branch 'jk/rev-list-verify-objects-fix'

"git rev-list --verify-objects" ought to inspect the contents of
objects and notice corrupted ones, but it didn't when the commit
graph is in use, which has been corrected.

* jk/rev-list-verify-objects-fix:
  rev-list: disable commit graph with --verify-objects
  lookup_commit_in_graph(): use prepare_commit_graph() to check for graph

commit-graph.c

@@ -901,7 +901,7 @@ struct commit *lookup_commit_in_graph(struct repository *repo, const struct obje
 	struct commit *commit;
 	uint32_t pos;
 
-	if (!repo->objects->commit_graph)
+	if (!prepare_commit_graph(repo))
 		return NULL;
 	if (!search_commit_pos_in_graph(id, repo->objects->commit_graph, &pos))
 		return NULL;

revision.c

@@ -2418,6 +2418,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 		revs->tree_objects = 1;
 		revs->blob_objects = 1;
 		revs->verify_objects = 1;
+		disable_commit_graph(revs->repo);
 	} else if (!strcmp(arg, "--unpacked")) {
 		revs->unpacked = 1;
 	} else if (starts_with(arg, "--unpacked=")) {

t/t1450-fsck.sh

@@ -527,6 +527,34 @@ test_expect_success 'rev-list --verify-objects notices swapped commits' '
 	)
 '
 
+test_expect_success 'set up repository with commit-graph' '
+	git init corrupt-graph &&
+	(
+		cd corrupt-graph &&
+		test_commit one &&
+		test_commit two &&
+		git commit-graph write --reachable
+	)
+'
+
+corrupt_graph_obj () {
+	oid=$(git -C corrupt-graph rev-parse "$1") &&
+	obj=corrupt-graph/.git/objects/$(test_oid_to_path $oid) &&
+	test_when_finished 'mv backup $obj' &&
+	mv $obj backup &&
+	echo garbage >$obj
+}
+
+test_expect_success 'rev-list --verify-objects with commit graph (tip)' '
+	corrupt_graph_obj HEAD &&
+	test_must_fail git -C corrupt-graph rev-list --verify-objects HEAD
+'
+
+test_expect_success 'rev-list --verify-objects with commit graph (parent)' '
+	corrupt_graph_obj HEAD^ &&
+	test_must_fail git -C corrupt-graph rev-list --verify-objects HEAD
+'
+
 test_expect_success 'force fsck to ignore double author' '
 	git cat-file commit HEAD >basis &&
 	sed "s/^author .*/&,&/" <basis | tr , \\n >multiple-authors &&