Add return types to internal & magic methods when possible

Author: nicolas-grekas

Authentication/Token/AbstractToken.php

@@ -163,10 +163,9 @@ public function __serialize(): array
     }
 
     /**
-     * {@inheritdoc}
+     * @return string
      *
      * @final since Symfony 4.3, use __serialize() instead
-     *
      * @internal since Symfony 4.3, use __serialize() instead
      */
     public function serialize()

Exception/AuthenticationException.php

@@ -113,7 +113,7 @@ public function unserialize($serialized)
     /**
      * @internal
      */
-    public function __sleep()
+    public function __sleep(): array
     {
         if (__CLASS__ !== $c = (new \ReflectionMethod($this, 'serialize'))->getDeclaringClass()->name) {
             @trigger_error(sprintf('Implementing the "%s::serialize()" method is deprecated since Symfony 4.3, implement the __serialize() and __unserialize() methods instead.', $c), E_USER_DEPRECATED);

Tests/Authentication/AuthenticationTrustResolverTest.php

@@ -152,7 +152,7 @@ public function __serialize(): array
     {
     }
 
-    public function serialize()
+    public function serialize(): string
     {
     }
 

Tests/Authentication/Token/AbstractTokenTest.php

@@ -259,7 +259,7 @@ public function __construct($name)
         $this->name = $name;
     }
 
-    public function __toString()
+    public function __toString(): string
     {
         return $this->name;
     }

Tests/SecurityTest.php

@@ -122,7 +122,7 @@ private function createContainer($serviceId, $serviceObject)
 
 class StringishUser
 {
-    public function __toString()
+    public function __toString(): string
     {
         return 'stringish_user';
     }

User/User.php

@@ -45,7 +45,7 @@ public function __construct(?string $username, ?string $password, array $roles =
         $this->extraFields = $extraFields;
     }
 
-    public function __toString()
+    public function __toString(): string
     {
         return $this->getUsername();
     }