diff --git a/src/Symfony/Component/HttpClient/Response/HttplugPromise.php b/src/Symfony/Component/HttpClient/Response/HttplugPromise.php
index f3806c9e53..01c59f75b4 100644
--- a/src/Symfony/Component/HttpClient/Response/HttplugPromise.php
+++ b/src/Symfony/Component/HttpClient/Response/HttplugPromise.php
@@ -49,10 +49,8 @@ final class HttplugPromise implements HttplugPromiseInterface
 
     /**
      * {@inheritdoc}
-     *
-     * @return Psr7ResponseInterface|mixed
      */
-    public function wait($unwrap = true)
+    public function wait($unwrap = true): ?Psr7ResponseInterface
     {
         $result = $this->promise->wait($unwrap);
 
diff --git a/src/Symfony/Contracts/HttpClient/ResponseInterface.php b/src/Symfony/Contracts/HttpClient/ResponseInterface.php
index dfd457a45e..ad4a4687d8 100644
--- a/src/Symfony/Contracts/HttpClient/ResponseInterface.php
+++ b/src/Symfony/Contracts/HttpClient/ResponseInterface.php
@@ -104,8 +104,8 @@ interface ResponseInterface
      *
      * Other info SHOULD be named after curl_getinfo()'s associative return value.
      *
-     * @return array|mixed An array of all available info, or one of them when $type is
-     *                     provided, or null when an unsupported type is requested
+     * @return mixed An array of all available info, or one of them when $type is
+     *               provided, or null when an unsupported type is requested
      */
     public function getInfo(string $type = null);
 }