diff --git a/core/tests/Drupal/Tests/Core/Entity/FieldableDatabaseStorageControllerTest.php b/core/tests/Drupal/Tests/Core/Entity/FieldableDatabaseStorageControllerTest.php
index bb65e87..ab41926 100644
--- a/core/tests/Drupal/Tests/Core/Entity/FieldableDatabaseStorageControllerTest.php
+++ b/core/tests/Drupal/Tests/Core/Entity/FieldableDatabaseStorageControllerTest.php
@@ -99,6 +99,7 @@ public function testFieldSqlSchemaForEntityWithStringIdentifier() {
           'not null' => FALSE,
         ),
       ),
+      'unique keys' => array(),
       'indexes' => array(),
       'foreign keys' => array(),
     );