diff --git a/swh/search/tests/test_elasticsearch.py b/swh/search/tests/test_elasticsearch.py
index c59e173..8c5698b 100644
--- a/swh/search/tests/test_elasticsearch.py
+++ b/swh/search/tests/test_elasticsearch.py
@@ -15,7 +15,7 @@
 from .test_search import CommonSearchTest
 
 
-class BaseElasticsearchTest(unittest.TestCase):
+class BaseElasticsearchTest:
     @pytest.fixture(autouse=True)
     def _instantiate_search(self, swh_search, elasticsearch_host, mocker):
         self._elasticsearch_host = elasticsearch_host
@@ -56,7 +56,7 @@ def reset(self):
         self.search.initialize()
 
 
-class TestElasticsearchSearch(CommonSearchTest, BaseElasticsearchTest):
+class TestElasticsearchSearchTest(BaseElasticsearchTest):
     def test_metrics_update_duration(self):
         mock = self.mocker.patch("swh.search.metrics.statsd.timing")
 
diff --git a/swh/search/tests/test_in_memory.py b/swh/search/tests/test_in_memory.py
index 6ee2c06..87e867e 100644
--- a/swh/search/tests/test_in_memory.py
+++ b/swh/search/tests/test_in_memory.py
@@ -12,10 +12,11 @@
 from .test_search import CommonSearchTest
 
 
-class InmemorySearchTest(unittest.TestCase, CommonSearchTest):
+class TestInmemorySearchTest(CommonSearchTest):
     @pytest.fixture(autouse=True)
     def _instantiate_search(self):
         self.search = get_search("memory")
+        self.reset()
 
     def setUp(self):
         self.reset()