Issue #2120847 by tim.plunkett: Add test coverage for FormBuilder::sendResponse().

core/lib/Drupal/Core/Form/FormBuilder.php

@@ -274,6 +274,7 @@ public function buildForm($form_id, &$form_state) {
     // If the form returns some kind of response, deliver it.
     if ($response instanceof Response) {
       $this->sendResponse($response);
+      exit;
     }
 
     // If this was a successful submission of a single-step form or the last step
@@ -572,6 +573,7 @@ public function retrieveForm($form_id, &$form_state) {
     // If the form returns some kind of response, deliver it.
     if ($form instanceof Response) {
       $this->sendResponse($form);
+      exit;
     }
     $form['#form_id'] = $form_id;
 
@@ -1661,7 +1663,6 @@ protected function sendResponse(Response $response) {
       ->prepare($this->request)
       ->send();
     $this->httpKernel->terminate($this->request, $response);
-    exit;
   }
 
   /**

core/tests/Drupal/Tests/Core/Form/FormBuilderTest.php

@@ -14,6 +14,7 @@
 use Drupal\Tests\UnitTestCase;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
 
 /**
  * Tests the form builder.
@@ -101,8 +102,11 @@ public function setUp() {
     $this->csrfToken = $this->getMockBuilder('Drupal\Core\Access\CsrfTokenGenerator')
       ->disableOriginalConstructor()
       ->getMock();
+    $http_kernel = $this->getMockBuilder('Drupal\Core\HttpKernel')
+      ->disableOriginalConstructor()
+      ->getMock();
 
-    $this->formBuilder = new TestFormBuilder($this->moduleHandler, $key_value_expirable_factory, $event_dispatcher, $this->urlGenerator, $translation_manager, $this->csrfToken);
+    $this->formBuilder = new TestFormBuilder($this->moduleHandler, $key_value_expirable_factory, $event_dispatcher, $this->urlGenerator, $translation_manager, $this->csrfToken, $http_kernel);
     $this->formBuilder->setRequest(new Request());
 
     $this->account = $this->getMock('Drupal\Core\Session\AccountInterface');
@@ -475,6 +479,32 @@ public function testGetCache() {
     $this->formBuilder->buildForm($form_id, $form_state);
   }
 
+  /**
+   * Tests the sendResponse() method.
+   *
+   * @expectedException \Exception
+   */
+  public function testSendResponse() {
+    $form_id = 'test_form_id';
+    $expected_form = $this->getMockBuilder('Symfony\Component\HttpFoundation\Response')
+      ->disableOriginalConstructor()
+      ->getMock();
+    $expected_form->expects($this->once())
+      ->method('prepare')
+      ->will($this->returnValue($expected_form));
+
+    $form_arg = $this->getMock('Drupal\Core\Form\FormInterface');
+    $form_arg->expects($this->any())
+      ->method('buildForm')
+      ->will($this->returnValue($expected_form));
+
+    // Do an initial build of the form and track the build ID.
+    $form_state = array();
+    $form_state['build_info']['callback_object'] = $form_arg;
+    $form_state['build_info']['args'] = array();
+    $this->formBuilder->buildForm($form_id, $form_state);
+  }
+
   /**
    * Asserts that the expected form structure is found in a form for a given key.
    *
@@ -499,6 +529,15 @@ protected function assertFormElement(array $expected_form, array $actual_form, $
  */
 class TestFormBuilder extends FormBuilder {
 
+  /**
+   * {@inheritdoc}
+   */
+  protected function sendResponse(Response $response) {
+    parent::sendResponse($response);
+    // Throw an exception instead of exiting.
+    throw new \Exception('exit');
+  }
+
   /**
    * @param \Drupal\Core\Session\AccountInterface $account
    */