Issue #3278243: Add return type declarations

src/StackMiddleware/PrefetchCacheAfterSessionInitialized.php

 <?php
 
-/**
- * @file
- * Contains \Drupal\prefetch_cache\StackMiddleware\PrefetchCacheAfterSessionInitialized.
- */
-
 namespace Drupal\prefetch_cache\StackMiddleware;
 
 use Drupal\page_cache\StackMiddleware\PageCache;
@@ -17,11 +12,13 @@ use Drupal\prefetch_cache\PrefetchCacheInterface;
  * Executes the prefetch caching before the main kernel takes over the request.
  *
  * Runs after PrefetchCacheBeforePageCache, PageCache and Session.
- *
  */
 class PrefetchCacheAfterSessionInitialized extends PageCache {
 
-  public function handle(Request $request, $type = self::MASTER_REQUEST, $catch = TRUE) {
+  /**
+   * {@inheritdoc}
+   */
+  public function handle(Request $request, $type = self::MASTER_REQUEST, $catch = TRUE): Response {
     $response = NULL;
     $is_cache_request = $request->attributes->has(PrefetchCacheInterface::PREFETCH_CACHE_REQUEST);
     $has_token_id = $request->attributes->has(PrefetchCacheInterface::PREFETCH_CACHE_TOKEN_ID);
@@ -67,7 +64,7 @@ class PrefetchCacheAfterSessionInitialized extends PageCache {
   /**
    * {@inheritdoc}
    */
-  protected function getCacheId(Request $request)  {
+  protected function getCacheId(Request $request) {
     $cache_id = $request->attributes->get(PrefetchCacheInterface::PREFETCH_CACHE_CACHE_ID);
     if (!$cache_id) {
 

src/StackMiddleware/PrefetchCacheBeforePageCache.php

@@ -12,6 +12,7 @@ use Drupal\Component\Serialization\Json;
 use Drupal\page_cache\StackMiddleware\PageCache;
 use Drupal\Core\Cache\CacheBackendInterface;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\HttpKernel\HttpKernelInterface;
 use Drupal\prefetch_cache\PrefetchCacheInterface;
 use Drupal\prefetch_cache\Cache\ChainCacheTagsGeneratorInterface;
@@ -61,7 +62,7 @@ class PrefetchCacheBeforePageCache extends PageCache {
   /**
    * {@inheritdoc}
    */
-  public function handle(Request $request, $type = self::MASTER_REQUEST, $catch = TRUE) {
+  public function handle(Request $request, $type = self::MASTER_REQUEST, $catch = TRUE): Response {
     $response = NULL;
     $is_cache_request = $request->query->has(PrefetchCacheInterface::PREFETCH_CACHE_REQUEST);
     $has_token_id = $request->query->has(PrefetchCacheInterface::PREFETCH_CACHE_TOKEN_ID);
@@ -79,7 +80,6 @@ class PrefetchCacheBeforePageCache extends PageCache {
       $response = $this->httpKernel->handle($request, $type, $catch);
 
       // The response has been cached by page cache.
-
       if ($response->headers->contains('X-Drupal-Cache', 'HIT') || $response->headers->contains('X-Drupal-Cache', 'MISS')) {
         $response->setContent(Json::encode(['cached_by_page_cache' => TRUE]));
       }