diff --git a/core/modules/simpletest/tests/file.test b/core/modules/simpletest/tests/file.test
index 7496902..3a73c08 100644
--- a/core/modules/simpletest/tests/file.test
+++ b/core/modules/simpletest/tests/file.test
@@ -47,6 +47,8 @@ function file_test_file_scan_callback_reset() {
  * assertions and helper functions.
  */
 class FileTestCase extends DrupalWebTestCase {
+  protected $profile = 'testing';
+
   /**
    * Check that two files have the same values for all fields other than the
    * timestamp.