ViewRenderTest.php

<?php

declare (strict_types=1);
namespace Drupal\Tests\views\Kernel;

use Drupal\views\Views;

/**
 * Tests general rendering of a view.
 *
 * @group views
 */
class ViewRenderTest extends ViewsKernelTestBase {
  
  /**
   * {@inheritdoc}
   */
  public static $testViews = [
    'test_view_render',
  ];
  
  /**
   * Tests render functionality.
   */
  public function testRender() : void {
    $state = $this->container
      ->get('state');
    $state->set('views_render.test', 0);
    // Make sure that the rendering just calls the preprocess function once.
    $view = Views::getView('test_view_render');
    $output = $view->preview();
    $this->container
      ->get('renderer')
      ->renderRoot($output);
    $this->assertEquals(1, $state->get('views_render.test'));
  }

}