class AjaxRendererTest

class AjaxRendererTest extends UnitTestCase {
  
  /**
   * The tested ajax controller.
   *
   * @var \Drupal\Core\Render\MainContent\AjaxRenderer
   */
  protected $ajaxRenderer;
  
  /**
   * The renderer.
   *
   * @var \Drupal\Core\Render\RendererInterface|\PHPUnit\Framework\MockObject\MockObject
   */
  protected $renderer;
  
  /**
   * {@inheritdoc}
   */
  protected function setUp() : void {
    parent::setUp();
    $element_info_manager = $this->createMock('Drupal\\Core\\Render\\ElementInfoManagerInterface');
    $element_info_manager->expects($this->any())
      ->method('getInfo')
      ->with('ajax')
      ->willReturn([
      '#header' => TRUE,
      '#commands' => [],
      '#error' => NULL,
    ]);
    $renderer = $this->createMock(RendererInterface::class);
    $renderer->expects($this->any())
      ->method('renderRoot')
      ->willReturnCallback(function (&$elements, $is_root_call = FALSE) {
      $elements += [
        '#attached' => [],
      ];
      if (isset($elements['#markup'])) {
        return $elements['#markup'];
      }
      elseif (isset($elements['#type'])) {
        return $elements['#type'];
      }
      else {
        return 'Markup';
      }
    });
    $this->ajaxRenderer = new AjaxRenderer($element_info_manager, $renderer);
  }
  
  /**
   * Tests the content method.
   *
   * @covers ::renderResponse
   */
  public function testRenderWithFragmentObject() : void {
    $main_content = [
      '#markup' => 'example content',
    ];
    $request = new Request();
    $route_match = $this->createMock('Drupal\\Core\\Routing\\RouteMatchInterface');
    /** @var \Drupal\Core\Ajax\AjaxResponse $result */
    $result = $this->ajaxRenderer
      ->renderResponse($main_content, $request, $route_match);
    $this->assertInstanceOf('Drupal\\Core\\Ajax\\AjaxResponse', $result);
    $commands = $result->getCommands();
    $this->assertEquals('insert', $commands[0]['command']);
    $this->assertEquals('example content', $commands[0]['data']);
    $this->assertEquals('insert', $commands[1]['command']);
    $this->assertEquals('status_messages', $commands[1]['data']);
  }

}