diff --git a/core-test/core-units.c b/core-test/core-units.c
index a2fb24a..c202392 100644
--- a/core-test/core-units.c
+++ b/core-test/core-units.c
@@ -66,6 +66,7 @@ void test_btree_iterate(CuTest *tc)
 
 	b_btree tree = {0};
 	struct test_tree_node *nodes = calloc(nr_nodes, sizeof *nodes);
+	CuAssertPtrNotNull(tc, nodes);
 
 	for (int i = 0; i < nr_nodes; i++) {
 		nodes[i].value = rand();
@@ -84,7 +85,7 @@ void test_btree_iterate(CuTest *tc)
 			continue;
 		}
 
-		CuAssertTrue(tc, prev < node->value);
+		CuAssertTrue(tc, prev <= node->value);
 		prev = node->value;
 	}