Merge branch '4.4' into 5.3

* 4.4:
  Added a comment to the code
  Adds proper escaping for php service config format
  Note that parameter names for Attribute constructors are covered
  [DependencyInjection] add missing use statements

Author: javiereguiluz

contributing/code/bc.rst

@@ -448,8 +448,8 @@ Turn static into non static                         No
 
 .. [9] Allowed for the ``void`` return type.
 
-.. [10] Parameter names are not part of the compatibility promise. Using
-        PHP 8's named arguments feature might break your code when upgrading to
-        newer Symfony versions.
+.. [10] Parameter names are only covered by the compatibility promise for
+        constructors of Attribute classes. Using PHP named arguments might
+        break your code when upgrading to newer Symfony versions.
 
 .. _`Semantic Versioning`: https://semver.org/

service_container.rst

@@ -33,6 +33,7 @@ service's class or interface name. Want to :doc:`log </logging>` something? No p
 
     use Psr\Log\LoggerInterface;
     use Symfony\Component\HttpFoundation\Response;
+    use Symfony\Component\Routing\Annotation\Route;
 
     class ProductController
     {
@@ -119,6 +120,7 @@ inside your controller::
     // src/Controller/ProductController.php
     use App\Service\MessageGenerator;
     use Symfony\Component\HttpFoundation\Response;
+    use Symfony\Component\Routing\Annotation\Route;
 
     /**
      * @Route("/products/new")

service_container/expression_language.rst

@@ -67,7 +67,8 @@ to another service: ``App\Mailer``. One way to do this is with an expression:
             $services->set(MailerConfiguration::class);
 
             $services->set(Mailer::class)
-                ->args([expr("service('App\\Mail\\MailerConfiguration').getMailerMethod()")]);
+                // because of the escaping applied by PHP, you must add 4 backslashes for each original backslash
+                ->args([expr("service('App\\\\Mail\\\\MailerConfiguration').getMailerMethod()")]);
         };
 
 To learn more about the expression language syntax, see :doc:`/components/expression_language/syntax`.