diff --git a/tests/attachment/upload_test.php b/tests/attachment/upload_test.php
index 2743ee596d..0f4204dfff 100644
--- a/tests/attachment/upload_test.php
+++ b/tests/attachment/upload_test.php
@@ -79,6 +79,7 @@ class phpbb_attachment_upload_test extends \phpbb_database_test_case
 			'img_create_thumbnail'	=> true,
 		));
 		$config = $this->config;
+		$this->phpbb_root_path = $phpbb_root_path;
 		$this->db = $this->new_dbal();
 		$this->cache = new \phpbb\cache\service(new \phpbb\cache\driver\dummy(), $this->config, $this->db, $phpbb_root_path, $phpEx);
 		$this->request = $this->createMock('\phpbb\request\request');