class BaseThemeMissingTest

class BaseThemeMissingTest extends KernelTestBase {
  
  /**
   * The theme installer.
   *
   * @var \Drupal\Core\Extension\ThemeInstallerInterface
   */
  protected $themeInstaller;
  
  /**
   * {@inheritdoc}
   */
  protected function setUp() : void {
    parent::setUp();
    // Add a directory to extension discovery to find the theme with a missing
    // base class.
    // @see \Drupal\Core\Extension\ExtensionDiscovery::scan()
    $settings = Settings::getAll();
    $settings['test_parent_site'] = 'core/tests/fixtures/test_missing_base_theme';
    new Settings($settings);
    $this->themeInstaller = $this->container
      ->get('theme_installer');
  }
  
  /**
   * Tests exception is thrown.
   */
  public function testMissingBaseThemeException() : void {
    $this->expectException(InfoParserException::class);
    $this->expectExceptionMessage('Missing required key ("base theme") in core/tests/fixtures/test_missing_base_theme/test_missing_base_theme.info.yml, see https://www.drupal.org/node/3066038');
    $this->themeInstaller
      ->install([
      'test_missing_base_theme',
    ]);
  }

}