diff --git a/core/modules/system/lib/Drupal/system/Tests/Database/SelectTableSortDefaultTest.php b/core/modules/system/lib/Drupal/system/Tests/Database/SelectTableSortDefaultTest.php
index a50f38f954277380dd3b9f21d016fbaa7e9d41fa..bf1e81f4c9d1f893b7ef0523131c4f6351e6c075 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Database/SelectTableSortDefaultTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Database/SelectTableSortDefaultTest.php
@@ -79,7 +79,10 @@ function testTableSortQueryFirst() {
    */
   function testTableSortDefaultSort() {
     $this->drupalGet('database_test/tablesort_default_sort');
-    // Any PHP errors or notices thrown would trigger a simpletest exception, so
-    // no additional assertions are needed.
+
+    // Verify that the table was displayed. Just the header is checked for
+    // because if there were any fatal errors or exceptions in displaying the
+    // sorted table, it would not print the table.
+    $this->assertText(t('Username'));
   }
 }
diff --git a/core/modules/system/tests/modules/database_test/database_test.module b/core/modules/system/tests/modules/database_test/database_test.module
index 4500f741af50b07e16bfbd13d68eb5f4ea8795a8..d8428d8aab38dbc7aaee2247a79770ff2f0b7959 100644
--- a/core/modules/system/tests/modules/database_test/database_test.module
+++ b/core/modules/system/tests/modules/database_test/database_test.module
@@ -224,7 +224,7 @@ function database_test_theme_tablesort($form, &$form_state) {
 
   $query = $query
     ->extend('Drupal\Core\Database\Query\PagerSelectExtender')
-    ->extend('TableSort');
+    ->extend('Drupal\Core\Database\Query\TableSortExtender');
   $query
     ->fields('u', array('uid', 'name', 'status', 'created', 'access'))
     ->limit(50)