diff --git a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceAutocompleteTest.php b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceAutocompleteTest.php
index d388be4..7c7ba59 100644
--- a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceAutocompleteTest.php
+++ b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceAutocompleteTest.php
@@ -12,8 +12,8 @@
 use Drupal\Component\Utility\Tags;
 use Drupal\entity_reference\EntityReferenceController;
 use Drupal\system\Tests\Entity\EntityUnitTestBase;
-
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
 
 /**
  * Tests the autocomplete functionality of Entity Reference.
@@ -139,8 +139,6 @@ protected function getAutocompleteResult($type, $input) {
    * Tests autocomplete for entity base fields.
    */
   public function testBaseField() {
-    //entity_test_create_bundle('test_bundle');
-
     // Add two users.
     $user_1 = entity_create('user', array('name' => 'auto1'));
     $user_1->save();
@@ -156,6 +154,15 @@ public function testBaseField() {
     $data = Json::decode($result);
     $this->assertIdentical($data[0]['label'], String::checkPlain($user_1->getUsername()), 'Autocomplete returned the first matching entity');
     $this->assertIdentical($data[1]['label'], String::checkPlain($user_2->getUsername()), 'Autocomplete returned the second matching entity');
+
+    // Checks that exception thrown for unknown field.
+    try {
+      $entity_reference_controller->handleAutocomplete($request, 'single', 'unknown_field', 'entity_test', 'entity_test', 'NULL')->getContent();
+      $this->fail('Autocomplete throws exception for unknown field.');
+    }
+    catch (AccessDeniedHttpException $e) {
+      $this->pass('Autocomplete throws exception for unknown field.');
+    }
   }
 
 }