Added drupal_title Twig function.

src/TwigExtension.php

@@ -8,8 +8,10 @@ use Drupal\Core\Controller\TitleResolverInterface;
 use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\Form\FormBuilderInterface;
 use Drupal\Core\Menu\MenuLinkTreeInterface;
+use Drupal\Core\Render\RendererInterface;
 use Drupal\Core\Routing\RouteMatchInterface;
 use Drupal\Core\Site\Settings;
+use Drupal\Core\StringTranslation\TranslatableMarkup;
 use Drupal\Core\Utility\Token;
 use Drupal\image\Entity\ImageStyle;
 use Symfony\Cmf\Component\Routing\RouteObjectInterface;
@@ -76,6 +78,13 @@ class TwigExtension extends \Twig_Extension {
    */
   protected $formBuilder;
 
+  /**
+   * The renderer.
+   *
+   * @var \Drupal\Core\Render\RendererInterface
+   */
+  protected $renderer;
+
   /**
    * TwigExtension constructor.
    *
@@ -95,8 +104,10 @@ class TwigExtension extends \Twig_Extension {
    *   The title resolver.
    * @param \Drupal\Core\Form\FormBuilderInterface $form_builder
    *   The form builder.
+   * @param \Drupal\Core\Render\RendererInterface $renderer
+   *   The renderer.
    */
-  public function __construct(EntityTypeManagerInterface $entity_type_manager, Token $token, ConfigFactoryInterface $config_factory, RouteMatchInterface $route_match, MenuLinkTreeInterface $menu_tree, RequestStack $request_stack, TitleResolverInterface $title_resolver, FormBuilderInterface $form_builder) {
+  public function __construct(EntityTypeManagerInterface $entity_type_manager, Token $token, ConfigFactoryInterface $config_factory, RouteMatchInterface $route_match, MenuLinkTreeInterface $menu_tree, RequestStack $request_stack, TitleResolverInterface $title_resolver, FormBuilderInterface $form_builder, RendererInterface $renderer) {
     $this->entityTypeManager = $entity_type_manager;
     $this->token = $token;
     $this->configFactory = $config_factory;
@@ -105,6 +116,7 @@ class TwigExtension extends \Twig_Extension {
     $this->requestStack = $request_stack;
     $this->titleResolver = $title_resolver;
     $this->formBuilder = $form_builder;
+    $this->renderer = $renderer;
   }
 
   /**
@@ -126,6 +138,7 @@ class TwigExtension extends \Twig_Extension {
       // Wrap drupal_set_message() because it returns some value which is not
       // suitable for Twig template.
       new \Twig_SimpleFunction('drupal_set_message', [$this, 'drupalSetMessage']),
+      new \Twig_SimpleFunction('drupal_title', [$this, 'drupalTitle']),
     ];
   }
 
@@ -391,6 +404,23 @@ class TwigExtension extends \Twig_Extension {
     return $build;
   }
 
+  /**
+   * Returns a title for the current route.
+   *
+   * @return array
+   *   A render array to represent page title.
+   */
+  public function drupalTitle() {
+    $title = $this->titleResolver->getTitle(
+      $this->requestStack->getCurrentRequest(),
+      $this->routeMatch->getRouteObject()
+    );
+    $build['#markup'] = is_string($title) || $title instanceof TranslatableMarkup ?
+      $title : $this->renderer->render($title);
+    $build['#cache']['contexts'] = ['url'];
+    return $build;
+  }
+
   /**
    * Replaces all tokens in a given string with appropriate values.
    *

tests/src/Functional/TwigTweakTest.php

@@ -38,6 +38,8 @@ class TwigTweakTest extends BrowserTestBase {
    * Tests output produced by the Twig extension.
    */
   public function testOutput() {
+    // Title block rendered through drupal_region() is cached by some reason.
+    \Drupal::service('cache_tags.invalidator')->invalidateTags(['block_view']);
     $this->drupalGet('<front>');
 
     // Test default views display.
@@ -131,6 +133,10 @@ class TwigTweakTest extends BrowserTestBase {
     $xpath = '//div[@class = "messages messages--warning" and contains(., "Hi!")]';
     $this->assertByXpath($xpath);
 
+    // Test page title.
+    $xpath = '//div[@class = "tt-title" and text() = "Beta"]';
+    $this->assertByXpath($xpath);
+
     // Test token replacement.
     $xpath = '//div[@class = "tt-token-replace" and text() = "Site name: Drupal"]';
     $this->assertByXpath($xpath);
@@ -151,13 +157,4 @@ class TwigTweakTest extends BrowserTestBase {
     $this->assertSession()->elementExists('xpath', $xpath);
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  protected function drupalGet($path, array $options = [], array $headers = []) {
-    // Title block rendered through drupal_region() is cached by some reason.
-    \Drupal::service('cache_tags.invalidator')->invalidateTags(['block_view']);
-    return parent::drupalGet($path, $options, $headers);
-  }
-
 }

tests/twig_tweak_test/templates/twig-tweak-test.html.twig

@@ -33,6 +33,7 @@
   <div class="tt-token-data">{{ drupal_token('node:title', {'node': node}) }}</div>
   <div class="tt-config">{{ drupal_config('user.settings', 'anonymous') }}</div>
   <div class="tt-status-message">{{ drupal_set_message('Hi!', 'warning') }}</div>
+  <div class="tt-title">{{ drupal_title() }}</div>
   <div class="tt-token-replace">{{ 'Site name: [site:name]' | token_replace }}</div>
   <div class="tt-preg-replace">{{ 'foo' | preg_replace('(foo)', '$1-bar') }}</div>
   <div class="tt-image-style">{{ 'public://images/ocean.jpg' | image_style('thumbnail') }}</div>

twig_tweak.services.yml

@@ -10,5 +10,6 @@ services:
       - '@request_stack'
       - '@title_resolver'
       - '@form_builder'
+      - '@renderer'
     tags:
       - { name: twig.extension }