bloom: parse commit before computing filters

When computing changed-path Bloom filters for a commit, we need to
know if the commit has a parent or not. If the commit is not parsed,
then its parent pointer will be NULL.

As far as I can tell, the only opportunity to reach this code
without parsing the commit is inside "test-tool bloom
get_filter_for_commit" but it is best to be safe.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/bloom.c b/bloom.c
index 2e3e0f5037..9679278271 100644
--- a/bloom.c
+++ b/bloom.c
@@ -193,6 +193,9 @@ struct bloom_filter *get_bloom_filter(struct repository *r,
 	diffopt.max_changes = max_changes;
 	diff_setup_done(&diffopt);
 
+	/* ensure commit is parsed so we have parent information */
+	repo_parse_commit(r, c);
+
 	if (c->parents)
 		diff_tree_oid(&c->parents->item->object.oid, &c->object.oid, "", &diffopt);
 	else