Add `git_graph_descendant_of`.

1 files changed, 14 insertions, 0 deletions

diff --git a/src/graph.c b/src/graph.c
index 277f588ca..f39af5ed5 100644
--- a/src/graph.c
+++ b/src/graph.c
@@ -176,3 +176,17 @@ on_error:
 	git_revwalk_free(walk);
 	return -1;
 }
+
+int git_graph_descendant_of(git_repository *repo, const git_oid *commit, const git_oid *ancestor)
+{
+	git_oid merge_base;
+	int error;
+
+	if (git_oid_equal(commit, ancestor))
+		return 0;
+
+	if ((error = git_merge_base(&merge_base, repo, commit, ancestor) < 0))
+		return error;
+
+	return git_oid_equal(&merge_base, ancestor);
+}