diff --git a/datatree/tests/test_mapping.py b/datatree/tests/test_mapping.py
index 242f998f..894b0480 100644
--- a/datatree/tests/test_mapping.py
+++ b/datatree/tests/test_mapping.py
@@ -259,7 +259,8 @@ def test_skip_empty_nodes_with_attrs(self, create_test_datatree):
 
         def check_for_data(ds):
             # fails if run on a node that has no data
-            assert len(ds.variables) == 0
+            assert len(ds.variables) != 0
+            return ds
 
         dt.map_over_subtree(check_for_data)