EngineNyanCatTest.php

<?php

declare (strict_types=1);
namespace Drupal\Tests\system\Functional\Theme;

use Drupal\Tests\BrowserTestBase;
// cspell:ignore nyan

/**
 * Tests the multi theme engine support.
 *
 * @group Theme
 */
class EngineNyanCatTest extends BrowserTestBase {
  
  /**
   * {@inheritdoc}
   */
  protected static $modules = [
    'theme_test',
  ];
  
  /**
   * {@inheritdoc}
   */
  protected $defaultTheme = 'stark';
  
  /**
   * {@inheritdoc}
   */
  protected function setUp() : void {
    parent::setUp();
    \Drupal::service('theme_installer')->install([
      'test_theme_nyan_cat_engine',
    ]);
  }
  
  /**
   * Ensures a theme's template is overridable based on the 'template' filename.
   */
  public function testTemplateOverride() : void {
    $this->config('system.theme')
      ->set('default', 'test_theme_nyan_cat_engine')
      ->save();
    $this->drupalGet('theme-test/template-test');
    $this->assertSession()
      ->pageTextContains('Success: Template overridden with Nyan Cat theme. All of them');
  }

}