1 files changed, 1 insertions, 1 deletions

diff --git a/tests/config/test_util.py b/tests/config/test_util.py

index 3d4929daac..7073654832 100644
--- a/tests/config/test_util.py
+++ b/tests/config/test_util.py
@@ -21,7 +21,7 @@ from tests.unittest import TestCase
 class ValidateConfigTestCase(TestCase):
     """Test cases for synapse.config._util.validate_config"""
 
-    def test_bad_object_in_array(self):
+    def test_bad_object_in_array(self) -> None:
         """malformed objects within an array should be validated correctly"""
 
         # consider a structure: