diff -u b/core/tests/Drupal/FunctionalTests/BrowserTestBaseTest.php b/core/tests/Drupal/FunctionalTests/BrowserTestBaseTest.php
--- b/core/tests/Drupal/FunctionalTests/BrowserTestBaseTest.php
+++ b/core/tests/Drupal/FunctionalTests/BrowserTestBaseTest.php
@@ -198,14 +198,13 @@
     }
 
     $this->assertFieldByName('checkbox_enabled', TRUE);
-    $this->assertFieldByName('checkbox_disabled', FALSE);
+    $this->assertFieldByName('checkbox_disabled');
 
     $this->assertNoFieldByName('checkbox_enabled', FALSE);
-    $this->assertNoFieldByName('checkbox_disabled', TRUE);
 
     try {
       $this->assertFieldByName('checkbox_enabled', FALSE);
-      $this->fail('The checked "checkbox_enableRd" field was not found.');
+      $this->fail('The checked "checkbox_enabled" field was not found.');
 
     }
     catch (\PHPUnit_Framework_ExpectationFailedException $e) {