class TermHierarchyTest

class TermHierarchyTest extends KernelTestBase {
  use UserCreationTrait;
  use BlockCreationTrait;
  use TaxonomyTestTrait;
  
  /**
   * {@inheritdoc}
   */
  protected static $modules = [
    'system',
    'user',
    'block',
    'node',
    'filter',
    'text',
    'taxonomy',
  ];
  
  /**
   * {@inheritdoc}
   */
  protected function setUp() : void {
    parent::setUp();
    $this->installConfig([
      'filter',
    ]);
    $this->installEntitySchema('taxonomy_term');
    $this->installEntitySchema('user');
    $this->container
      ->get('theme_installer')
      ->install([
      'stark',
    ]);
    $this->container
      ->get('theme.manager')
      ->setActiveTheme($this->container
      ->get('theme.initialization')
      ->initTheme('stark'));
    $this->placeBlock('system_breadcrumb_block', [
      'region' => 'content',
      'theme' => 'stark',
    ]);
    $this->setUpCurrentUser(permissions: [
      'administer taxonomy',
      'bypass node access',
    ]);
  }
  
  /**
   * Tests that there is a link to the parent term on the child term page.
   */
  public function testTaxonomyTermHierarchyBreadcrumbs() : void {
    $vocabulary = $this->createVocabulary();
    // Create two taxonomy terms and set term2 as the parent of term1.
    $term1 = $this->createTerm($vocabulary);
    $term2 = $this->createTerm($vocabulary);
    $term1->parent = [
      $term2->id(),
    ];
    $term1->save();
    // Verify that the page breadcrumbs include a link to the parent term.
    $this->drupalGet('taxonomy/term/' . $term1->id());
    // Breadcrumbs are not rendered with a language, prevent the term
    // language from being added to the options.
    // Check that parent term link is displayed when viewing the node.
    $this->assertSession()
      ->responseContains(Link::fromTextAndUrl($term2->getName(), $term2->toUrl('canonical', [
      'language' => NULL,
    ]))
      ->toString());
  }

}