Subject: [PATCH 1/6] object.c: parse commit in graph first

From: Derrick Stolee <[email-masked]>
Date: Tue, 3 Apr 2018 12:51:38 -0400

Most code paths load commits using lookup_commit() and then
parse_commit(). In some cases, including some branch lookups, the commit
is parsed using parse_object_buffer() which side-steps parse_commit() in
favor of parse_commit_buffer().

Before adding generation numbers to the commit-graph, we need to ensure
that any commit that exists in the graph is loaded from the graph, so
check parse_commit_in_graph() before calling parse_commit_buffer().

Signed-off-by: Derrick Stolee <[email-masked]>
---
 object.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/object.c b/object.c
index e6ad3f61f0..4cd3e98e04 100644
--- a/object.c
+++ b/object.c
@@ -3,6 +3,7 @@
 #include "blob.h"
 #include "tree.h"
 #include "commit.h"
+#include "commit-graph.h"
 #include "tag.h"
 
 static struct object **obj_hash;
@@ -207,7 +208,8 @@ struct object *parse_object_buffer(const struct object_id *oid, enum object_type
 	} else if (type == OBJ_COMMIT) {
 		struct commit *commit = lookup_commit(oid);
 		if (commit) {
-			if (parse_commit_buffer(commit, buffer, size))
+			if (!parse_commit_in_graph(commit) &&
+			    parse_commit_buffer(commit, buffer, size))
 				return NULL;
 			if (!get_cached_commit_buffer(commit, NULL)) {
 				set_commit_buffer(commit, buffer, size);
-- 
2.17.0.rc0