diff --git a/tests/search/mysql_test.php b/tests/search/mysql_test.php
index 3ba3915714..3ad15bd806 100644
--- a/tests/search/mysql_test.php
+++ b/tests/search/mysql_test.php
@@ -26,7 +26,7 @@ class phpbb_search_mysql_test extends phpbb_search_common_test_case
 		parent::setUp();
 
 		// dbal uses cache
-		$cache = new phpbb_cache_service(new phpbb_cache_driver_null);
+		$cache = new phpbb_mock_cache();
 
 		//  set config values
 		$config['fulltext_mysql_min_word_len'] = 4;
diff --git a/tests/search/native_test.php b/tests/search/native_test.php
index eeee3a44f3..4a2c210013 100644
--- a/tests/search/native_test.php
+++ b/tests/search/native_test.php
@@ -26,7 +26,7 @@ class phpbb_search_native_test extends phpbb_search_test_case
 		parent::setUp();
 
 		// dbal uses cache
-		$cache = new phpbb_cache_service(new phpbb_cache_driver_null);
+		$cache = new phpbb_mock_cache();
 
 		$this->db = $this->new_dbal();
 		$error = null;
diff --git a/tests/search/postgres_test.php b/tests/search/postgres_test.php
index 9c77e0c09e..923af6f854 100644
--- a/tests/search/postgres_test.php
+++ b/tests/search/postgres_test.php
@@ -26,7 +26,7 @@ class phpbb_search_postgres_test extends phpbb_search_common_test_case
 		parent::setUp();
 
 		// dbal uses cache
-		$cache = new phpbb_cache_service(new phpbb_cache_driver_null);
+		$cache = new phpbb_mock_cache();
 
 		//  set config values
 		$config['fulltext_postgres_min_word_len'] = 4;