diff --git a/object.c b/object.c
index 14188453c56..07fcf23d7b3 100644
--- a/object.c
+++ b/object.c
@@ -185,6 +185,24 @@ struct object *lookup_unknown_object(struct repository *r, const struct object_i
 	return obj;
 }
 
+struct object *lookup_object_by_type(struct repository *r,
+			    const struct object_id *oid,
+			    enum object_type type)
+{
+	switch (type) {
+	case OBJ_COMMIT:
+		return (struct object *)lookup_commit(r, oid);
+	case OBJ_TREE:
+		return (struct object *)lookup_tree(r, oid);
+	case OBJ_TAG:
+		return (struct object *)lookup_tag(r, oid);
+	case OBJ_BLOB:
+		return (struct object *)lookup_blob(r, oid);
+	default:
+		die("BUG: unknown object type %d", type);
+	}
+}
+
 struct object *parse_object_buffer(struct repository *r, const struct object_id *oid, enum object_type type, unsigned long size, void *buffer, int *eaten_p)
 {
 	struct object *obj;
diff --git a/object.h b/object.h
index eb7e481c39a..3b38c9cc988 100644
--- a/object.h
+++ b/object.h
@@ -158,6 +158,13 @@ struct object *parse_object_buffer(struct repository *r, const struct object_id
  */
 struct object *lookup_unknown_object(struct repository *r, const struct object_id *oid);
 
+/*
+ * Dispatch to the appropriate lookup_blob(), lookup_commit(), etc, based on
+ * "type".
+ */
+struct object *lookup_object_by_type(struct repository *r, const struct object_id *oid,
+				     enum object_type type);
+
 struct object_list *object_list_insert(struct object *item,
 				       struct object_list **list_p);
 
diff --git a/reachable.c b/reachable.c
index c59847257a5..84e3d0d75ed 100644
--- a/reachable.c
+++ b/reachable.c
@@ -159,24 +159,6 @@ int add_unseen_recent_objects_to_traversal(struct rev_info *revs,
 				      FOR_EACH_OBJECT_LOCAL_ONLY);
 }
 
-static void *lookup_object_by_type(struct repository *r,
-				   const struct object_id *oid,
-				   enum object_type type)
-{
-	switch (type) {
-	case OBJ_COMMIT:
-		return lookup_commit(r, oid);
-	case OBJ_TREE:
-		return lookup_tree(r, oid);
-	case OBJ_TAG:
-		return lookup_tag(r, oid);
-	case OBJ_BLOB:
-		return lookup_blob(r, oid);
-	default:
-		die("BUG: unknown object type %d", type);
-	}
-}
-
 static int mark_object_seen(const struct object_id *oid,
 			     enum object_type type,
 			     int exclude,