diff --git a/tests/unit/test_footprinter.cc b/tests/unit/test_footprinter.cc
index 8ae2a2c0..7d984372 100644
--- a/tests/unit/test_footprinter.cc
+++ b/tests/unit/test_footprinter.cc
@@ -598,6 +598,11 @@ struct TestNoSerialize {
   int i;
 };
 
+static_assert(
+  not SerializableTraits<TestNoSerialize>::is_traversable,
+  "TestNoSerialize has no serializer defined"
+);
+
 TEST_F(TestFootprinter, test_no_serialize) {
   std::vector<TestNoSerialize> v(7);
 
@@ -605,5 +610,16 @@ TEST_F(TestFootprinter, test_no_serialize) {
     checkpoint::getMemoryFootprint(v),
     sizeof(v) + v.capacity() * sizeof(TestNoSerialize)
   );
+
+  std::unordered_map<int, TestNoSerialize> m;
+  m[1] = TestNoSerialize();
+  m[2] = TestNoSerialize();
+  m[3] = TestNoSerialize();
+  auto p = *m.begin();
+
+  EXPECT_EQ(
+    checkpoint::getMemoryFootprint(m),
+    sizeof(m) + m.size() * (sizeof(p) + sizeof(p.first) + sizeof(p.second))
+  );
 }
 }}} // end namespace checkpoint::tests::unit