diff --git a/src/Symfony/Bundle/FrameworkBundle/Secrets/SodiumVault.php b/src/Symfony/Bundle/FrameworkBundle/Secrets/SodiumVault.php
index cc1e443232..5b11704e7a 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Secrets/SodiumVault.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Secrets/SodiumVault.php
@@ -90,7 +90,7 @@ class SodiumVault extends AbstractVault implements EnvVarLoaderInterface
         $list = $this->list();
         $list[$name] = null;
         uksort($list, 'strnatcmp');
-        file_put_contents($this->pathPrefix.'list.php', sprintf("<?php\n\nreturn %s;\n", VarExporter::export($list), \LOCK_EX));
+        file_put_contents($this->pathPrefix.'list.php', sprintf("<?php\n\nreturn %s;\n", VarExporter::export($list)), \LOCK_EX);
 
         $this->lastMessage = sprintf('Secret "%s" encrypted in "%s"; you can commit it.', $name, $this->getPrettyPath(\dirname($this->pathPrefix).\DIRECTORY_SEPARATOR));
     }
@@ -142,7 +142,7 @@ class SodiumVault extends AbstractVault implements EnvVarLoaderInterface
 
         $list = $this->list();
         unset($list[$name]);
-        file_put_contents($this->pathPrefix.'list.php', sprintf("<?php\n\nreturn %s;\n", VarExporter::export($list), \LOCK_EX));
+        file_put_contents($this->pathPrefix.'list.php', sprintf("<?php\n\nreturn %s;\n", VarExporter::export($list)), \LOCK_EX);
 
         $this->lastMessage = sprintf('Secret "%s" removed from "%s".', $name, $this->getPrettyPath(\dirname($this->pathPrefix).\DIRECTORY_SEPARATOR));
 
diff --git a/src/Symfony/Contracts/Cache/CacheTrait.php b/src/Symfony/Contracts/Cache/CacheTrait.php
index 0374e1ddd5..d340e06962 100644
--- a/src/Symfony/Contracts/Cache/CacheTrait.php
+++ b/src/Symfony/Contracts/Cache/CacheTrait.php
@@ -27,6 +27,8 @@ trait CacheTrait
 {
     /**
      * {@inheritdoc}
+     *
+     * @return mixed
      */
     public function get(string $key, callable $callback, float $beta = null, array &$metadata = null)
     {
diff --git a/src/Symfony/Contracts/HttpClient/Test/TestHttpServer.php b/src/Symfony/Contracts/HttpClient/Test/TestHttpServer.php
index 1af9130f96..55a744aef4 100644
--- a/src/Symfony/Contracts/HttpClient/Test/TestHttpServer.php
+++ b/src/Symfony/Contracts/HttpClient/Test/TestHttpServer.php
@@ -18,6 +18,9 @@ class TestHttpServer
 {
     private static $process = [];
 
+    /**
+     * @return Process
+     */
     public static function start(int $port = 8057)
     {
         if (isset(self::$process[$port])) {
diff --git a/src/Symfony/Contracts/Service/ServiceSubscriberTrait.php b/src/Symfony/Contracts/Service/ServiceSubscriberTrait.php
index 243e10328f..cba072937d 100644
--- a/src/Symfony/Contracts/Service/ServiceSubscriberTrait.php
+++ b/src/Symfony/Contracts/Service/ServiceSubscriberTrait.php
@@ -52,6 +52,8 @@ trait ServiceSubscriberTrait
 
     /**
      * @required
+     *
+     * @return ContainerInterface|null
      */
     public function setContainer(ContainerInterface $container)
     {
diff --git a/src/Symfony/Contracts/Service/Test/ServiceLocatorTest.php b/src/Symfony/Contracts/Service/Test/ServiceLocatorTest.php
index d5b82674fa..2a1b565f50 100644
--- a/src/Symfony/Contracts/Service/Test/ServiceLocatorTest.php
+++ b/src/Symfony/Contracts/Service/Test/ServiceLocatorTest.php
@@ -17,6 +17,9 @@ use Symfony\Contracts\Service\ServiceLocatorTrait;
 
 abstract class ServiceLocatorTest extends TestCase
 {
+    /**
+     * @return ContainerInterface
+     */
     protected function getServiceLocator(array $factories)
     {
         return new class($factories) implements ContainerInterface {
diff --git a/src/Symfony/Contracts/Tests/Service/ServiceSubscriberTraitTest.php b/src/Symfony/Contracts/Tests/Service/ServiceSubscriberTraitTest.php
index 344bba8772..7d1ddd75c2 100644
--- a/src/Symfony/Contracts/Tests/Service/ServiceSubscriberTraitTest.php
+++ b/src/Symfony/Contracts/Tests/Service/ServiceSubscriberTraitTest.php
@@ -42,7 +42,7 @@ class ParentTestService
     {
     }
 
-    public function setContainer(ContainerInterface $container)
+    public function setContainer(ContainerInterface $container): ContainerInterface
     {
         return $container;
     }
diff --git a/src/Symfony/Contracts/Translation/Test/TranslatorTest.php b/src/Symfony/Contracts/Translation/Test/TranslatorTest.php
index 528a06dab7..cb3dccbce7 100644
--- a/src/Symfony/Contracts/Translation/Test/TranslatorTest.php
+++ b/src/Symfony/Contracts/Translation/Test/TranslatorTest.php
@@ -43,6 +43,9 @@ class TranslatorTest extends TestCase
         \Locale::setDefault($this->defaultLocale);
     }
 
+    /**
+     * @return TranslatorInterface
+     */
     public function getTranslator()
     {
         return new class() implements TranslatorInterface {