diff --git a/phpBB/includes/functions_install.php b/phpBB/includes/functions_install.php
index 2e10db6b24..eae136808c 100644
--- a/phpBB/includes/functions_install.php
+++ b/phpBB/includes/functions_install.php
@@ -586,7 +586,6 @@ function phpbb_create_config_file_data($data, $dbms, $load_extensions, $debug =
 	{
 		$config_data .= "@define('DEBUG', true);\n";
 		$config_data .= "@define('DEBUG_EXTRA', true);\n";
-		$config_data .= "@define('DEBUG_TEST', true);\n";
 	}
 	else
 	{
@@ -594,6 +593,11 @@ function phpbb_create_config_file_data($data, $dbms, $load_extensions, $debug =
 		$config_data .= "// @define('DEBUG_EXTRA', true);\n";
 	}
 
+	if ($debug_test)
+	{
+		$config_data .= "@define('DEBUG_TEST', true);\n";
+	}
+
 	return $config_data;
 }
 
diff --git a/tests/test_framework/phpbb_functional_test_case.php b/tests/test_framework/phpbb_functional_test_case.php
index 2423299b7c..d35913e415 100644
--- a/tests/test_framework/phpbb_functional_test_case.php
+++ b/tests/test_framework/phpbb_functional_test_case.php
@@ -140,7 +140,7 @@ class phpbb_functional_test_case extends phpbb_test_case
 		$this->do_request('create_table', $data);
 
 		$this->do_request('config_file', $data);
-		file_put_contents($phpbb_root_path . "config.$phpEx", phpbb_create_config_file_data($data, self::$config['dbms'], array(), true));
+		file_put_contents($phpbb_root_path . "config.$phpEx", phpbb_create_config_file_data($data, self::$config['dbms'], array(), true, true));
 
 		$this->do_request('final', $data);
 		copy($phpbb_root_path . "config.$phpEx", $phpbb_root_path . "config_test.$phpEx");