EWPP-3782: Ensure language specific redirects work.

modules/oe_multilingual_url_suffix/oe_multilingual_url_suffix.module

@@ -8,7 +8,9 @@
 declare(strict_types=1);
 
 use Drupal\Core\Hook\Attribute\LegacyHook;
+use Drupal\Core\Routing\TrustedRedirectResponse;
 use Drupal\oe_multilingual_url_suffix\Hook\OeMultilingualUrlSuffixHooks;
+use Drupal\redirect\Entity\Redirect;
 
 /**
  * Implements hook_language_types_info_alter().
@@ -27,3 +29,13 @@ use Drupal\oe_multilingual_url_suffix\Hook\OeMultilingualUrlSuffixHooks;
 function oe_multilingual_url_suffix_language_types_info_alter(array &$language_types) {
   return \Drupal::service(OeMultilingualUrlSuffixHooks::class)->languageTypesInfoAlter($language_types);
 }
+
+/**
+ * Implements hook_redirect_response_alter().
+ *
+ * @phpstan-ignore-next-line
+ */
+#[LegacyHook]
+function oe_multilingual_url_suffix_redirect_response_alter(TrustedRedirectResponse $response, Redirect $redirect) {
+  return \Drupal::service(OeMultilingualUrlSuffixHooks::class)->redirectResponseAlter($response, $redirect);
+}

modules/oe_multilingual_url_suffix/src/Hook/OeMultilingualUrlSuffixHooks.php

@@ -4,16 +4,48 @@
 
 namespace Drupal\oe_multilingual_url_suffix\Hook;
 
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Hook\Attribute\Hook;
+use Drupal\Core\Language\Language;
 use Drupal\Core\Language\LanguageInterface;
+use Drupal\Core\Language\LanguageManagerInterface;
+use Drupal\Core\Routing\TrustedRedirectResponse;
 use Drupal\language\Plugin\LanguageNegotiation\LanguageNegotiationUrlFallback;
 use Drupal\oe_multilingual_url_suffix\Plugin\LanguageNegotiation\LanguageNegotiationUrlSuffix;
+use Drupal\redirect\Entity\Redirect;
 
 /**
  * Hook implementations for OE Multilingual URL Suffix module.
  */
 class OeMultilingualUrlSuffixHooks {
 
+  /**
+   * The language manager.
+   *
+   * @var \Drupal\Core\Language\LanguageManagerInterface
+   */
+  protected LanguageManagerInterface $languageManager;
+
+  /**
+   * The config factory.
+   *
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
+   */
+  protected ConfigFactoryInterface $configFactory;
+
+  /**
+   * Constructs an OeMultilingualUrlSuffixHooks object.
+   *
+   * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
+   *   The language manager.
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
+   *   The config factory.
+   */
+  public function __construct(LanguageManagerInterface $language_manager, ConfigFactoryInterface $config_factory) {
+    $this->languageManager = $language_manager;
+    $this->configFactory = $config_factory;
+  }
+
   /**
    * Implements hook_language_types_info_alter().
    *
@@ -34,4 +66,93 @@ public function languageTypesInfoAlter(array &$language_types): void {
     ];
   }
 
+  /**
+   * Implements hook_redirect_response_alter().
+   *
+   * Ensures that redirects resolve to the correct language when using URL
+   * suffix language negotiation. Handles two cases:
+   * - When the redirect destination path contains an explicit language suffix
+   *   (e.g., /test-page_fr), the suffix is detected and used.
+   * - When the redirect entity has a specific language set, that language is
+   *   used instead of the current request's URL language.
+   *
+   * @param \Drupal\Core\Routing\TrustedRedirectResponse $response
+   *   The redirect response.
+   * @param \Drupal\redirect\Entity\Redirect $redirect
+   *   The redirect entity.
+   *
+   * @phpstan-ignore-next-line
+   */
+  #[Hook('redirect_response_alter')]
+  public function redirectResponseAlter(TrustedRedirectResponse $response, Redirect $redirect): void {
+    // First, check if the redirect destination path contains a language suffix.
+    $language = $this->detectDestinationLanguage($redirect);
+
+    // If no suffix language found, check the redirect entity's language field.
+    if (!$language) {
+      $redirect_langcode = $redirect->language()->getId();
+      if ($redirect_langcode === Language::LANGCODE_NOT_SPECIFIED) {
+        return;
+      }
+      $language = $this->languageManager->getLanguage($redirect_langcode);
+    }
+
+    if (!$language) {
+      return;
+    }
+
+    // If the detected language matches the current URL language, no change
+    // needed.
+    $current_language = $this->languageManager->getCurrentLanguage(LanguageInterface::TYPE_URL);
+    if ($current_language && $current_language->getId() === $language->getId()) {
+      return;
+    }
+
+    // Regenerate the URL with the correct language.
+    $url = $redirect->getRedirectUrl();
+    if ($url) {
+      $url->setOption('language', $language);
+      $response->setTrustedTargetUrl($url->setAbsolute()->toString());
+    }
+  }
+
+  /**
+   * Detects a language suffix in the redirect destination path.
+   *
+   * @param \Drupal\redirect\Entity\Redirect $redirect
+   *   The redirect entity.
+   *
+   * @return \Drupal\Core\Language\LanguageInterface|null
+   *   The language if a valid suffix was found, NULL otherwise.
+   */
+  protected function detectDestinationLanguage(Redirect $redirect): ?LanguageInterface {
+    $uri = $redirect->get('redirect_redirect')->uri;
+    if (!$uri) {
+      return NULL;
+    }
+
+    $path = parse_url($uri, PHP_URL_PATH);
+    if (!$path) {
+      return NULL;
+    }
+
+    $url_suffixes = $this->configFactory->get('oe_multilingual_url_suffix.settings')->get('url_suffixes');
+    if (empty($url_suffixes)) {
+      return NULL;
+    }
+
+    $parts = explode(LanguageNegotiationUrlSuffix::SUFFIX_DELIMITER, trim($path, '/'));
+    if (count($parts) < 2) {
+      return NULL;
+    }
+
+    $suffix = array_pop($parts);
+    $langcode = array_search($suffix, $url_suffixes);
+    if (!$langcode) {
+      return NULL;
+    }
+
+    return $this->languageManager->getLanguage($langcode);
+  }
+
 }

modules/oe_multilingual_url_suffix/src/Plugin/LanguageNegotiation/LanguageNegotiationUrlSuffix.php

@@ -161,7 +161,8 @@ public function processInbound($path, Request $request) {
 
       // If the suffix is one of the configured language suffix, rebuild the
       // path to remove it.
-      if (array_search($suffix, $url_suffixes)) {
+      $langcode = array_search($suffix, $url_suffixes);
+      if ($langcode) {
         $path = '/' . implode(static::SUFFIX_DELIMITER, $parts);
       }
     }

modules/oe_multilingual_url_suffix/tests/src/Functional/RedirectLanguageSuffixTest.php

@@ -0,0 +1,171 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\Tests\oe_multilingual_url_suffix\Functional;
+
+use Drupal\Core\Language\Language;
+use Drupal\node\Entity\Node;
+use Drupal\redirect\Entity\Redirect;
+use Drupal\Tests\BrowserTestBase;
+
+/**
+ * Tests redirect integration with URL suffix language negotiation.
+ *
+ * @group oe_multilingual_url_suffix
+ */
+class RedirectLanguageSuffixTest extends BrowserTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static $modules = [
+    'language',
+    'node',
+    'path',
+    'path_alias',
+    'redirect',
+    'oe_multilingual_url_suffix',
+    'content_translation',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected $defaultTheme = 'stark';
+
+  /**
+   * A test node with translations.
+   *
+   * @var \Drupal\node\NodeInterface
+   */
+  protected $node;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp(): void {
+    parent::setUp();
+
+    // Create an Article node type.
+    $this->drupalCreateContentType(['type' => 'article']);
+
+    // Enable content translation for articles.
+    $this->container->get('content_translation.manager')->setEnabled('node', 'article', TRUE);
+    $this->container->get('router.builder')->rebuild();
+
+    // Create a user with necessary permissions.
+    $user = $this->drupalCreateUser([
+      'administer languages',
+      'access administration pages',
+      'administer redirects',
+      'administer nodes',
+      'create article content',
+      'edit any article content',
+      'create url aliases',
+      'translate any entity',
+      'create content translations',
+    ]);
+    $this->drupalLogin($user);
+
+    // Enable URL suffix language detection.
+    $edit = [
+      'language_interface[enabled][oe-multilingual-url-suffix-negotiation-method]' => 1,
+      'language_interface[enabled][language-url]' => 0,
+      'language_content[enabled][oe-multilingual-url-suffix-negotiation-method]' => 1,
+      'language_content[enabled][language-url]' => 0,
+    ];
+    $this->drupalGet('admin/config/regional/language/detection');
+    $this->submitForm($edit, 'Save settings');
+
+    // Create a node with English and French translations.
+    $this->node = Node::create([
+      'type' => 'article',
+      'title' => 'English Title',
+      'langcode' => 'en',
+      'path' => ['alias' => '/test-page'],
+    ]);
+    $this->node->save();
+
+    $this->node->addTranslation('fr', [
+      'title' => 'French Title',
+      'path' => ['alias' => '/test-page'],
+    ]);
+    $this->node->save();
+  }
+
+  /**
+   * Tests redirect with path containing language suffix in destination.
+   */
+  public function testRedirectWithPathSuffixDestination(): void {
+    // Create a redirect using a path with French suffix as destination.
+    $redirect = Redirect::create([
+      'redirect_source' => 'my-redirect',
+      'redirect_redirect' => 'internal:/test-page_fr',
+      'language' => Language::LANGCODE_NOT_SPECIFIED,
+      'status_code' => 301,
+    ]);
+    $redirect->save();
+
+    // Visit without language suffix - should still redirect to French.
+    // Use 'external' => FALSE to skip client-side path processing, as the
+    // test process's PathProcessorLanguage may have stale processors cached
+    // from before the language negotiation configuration was changed.
+    $this->drupalGet('/my-redirect', ['external' => FALSE]);
+    $current_url = $this->getSession()->getCurrentUrl();
+    $this->assertStringContainsString('_fr', $current_url, 'Redirect should preserve French suffix from destination path.');
+    $this->assertSession()->pageTextContains('French Title');
+  }
+
+  /**
+   * Tests redirect with entity reference uses current request language.
+   */
+  public function testRedirectWithEntityReference(): void {
+    // Create a redirect to an entity, without specific language.
+    $redirect = Redirect::create([
+      'redirect_source' => 'entity-redirect',
+      'redirect_redirect' => 'internal:/node/' . $this->node->id(),
+      'language' => Language::LANGCODE_NOT_SPECIFIED,
+      'status_code' => 301,
+    ]);
+    $redirect->save();
+
+    // Visit without language suffix, current language defaults to English.
+    $this->drupalGet('/entity-redirect', ['external' => FALSE]);
+    $current_url = $this->getSession()->getCurrentUrl();
+    $this->assertStringContainsString('_en', $current_url, 'Entity redirect should use current language (English).');
+    $this->assertSession()->pageTextContains('English Title');
+
+    // Visit with French suffix, should redirect to French.
+    $this->drupalGet('/entity-redirect_fr', ['external' => FALSE]);
+    $current_url = $this->getSession()->getCurrentUrl();
+    $this->assertStringContainsString('_fr', $current_url, 'Entity redirect should use request language (French).');
+    $this->assertSession()->pageTextContains('French Title');
+  }
+
+  /**
+   * Tests that redirect Language field controls when redirect matches.
+   */
+  public function testRedirectLanguageFieldControlsMatching(): void {
+    // Create a redirect that only matches French requests.
+    $redirect = Redirect::create([
+      'redirect_source' => 'french-only',
+      'redirect_redirect' => 'internal:/node/' . $this->node->id(),
+      'language' => 'fr',
+      'status_code' => 301,
+    ]);
+    $redirect->save();
+
+    // Visit without French suffix, redirect should NOT match.
+    $this->drupalGet('/french-only', ['external' => FALSE]);
+    $current_url = $this->getSession()->getCurrentUrl();
+    $this->assertStringContainsString('french-only', $current_url, 'Redirect should not match non-French request.');
+
+    // Visit with French suffix, redirect should match.
+    $this->drupalGet('/french-only_fr', ['external' => FALSE]);
+    $current_url = $this->getSession()->getCurrentUrl();
+    $this->assertStringNotContainsString('french-only', $current_url, 'Redirect should match French request.');
+    $this->assertSession()->pageTextContains('French Title');
+  }
+
+}