minor #14419 [Container] Improve/fix container doc (noniagriconomie)

This PR was merged into the 4.4 branch.

Discussion
----------

[Container] Improve/fix container doc

Hi
This PR fixes mainly the `Swift_Mailer` leftover in favor of `Mailer` in the `SiteUpdateManager`
And also improves general code blocs for better understanding of reading flow

Commits
-------

31617f9 Improve/fix container doc

Author: javiereguiluz

service_container.rst

@@ -32,15 +32,16 @@ service's class or interface name. Want to :doc:`log </logging>` something? No p
     namespace App\Controller;
 
     use Psr\Log\LoggerInterface;
+    use Symfony\Component\HttpFoundation\Response;
 
     class ProductController
     {
         /**
          * @Route("/products")
          */
-        public function list(LoggerInterface $logger)
+        public function list(LoggerInterface $logger): Response
         {
-            $logger->info('Look! I just used a service');
+            $logger->info('Look, I just used a service!');
 
             // ...
         }
@@ -101,7 +102,7 @@ it can't be re-used. Instead, you decide to create a new class::
 
     class MessageGenerator
     {
-        public function getHappyMessage()
+        public function getHappyMessage(): string
         {
             $messages = [
                 'You did it! You updated the system! Amazing!',
@@ -118,9 +119,14 @@ it can't be re-used. Instead, you decide to create a new class::
 Congratulations! You've created your first service class! You can use it immediately
 inside your controller::
 
+    // src/Controller/ProductController.php
     use App\Service\MessageGenerator;
+    use Symfony\Component\HttpFoundation\Response;
 
-    public function new(MessageGenerator $messageGenerator)
+    /**
+     * @Route("/products/new")
+     */
+    public function new(MessageGenerator $messageGenerator): Response
     {
         // thanks to the type-hint, the container will instantiate a
         // new MessageGenerator and pass it to you!
@@ -241,7 +247,7 @@ and use it later::
             $this->logger = $logger;
         }
 
-        public function getHappyMessage()
+        public function getHappyMessage(): string
         {
             $this->logger->info('About to find a happy message!');
             // ...
@@ -291,8 +297,8 @@ Handling Multiple Services
 Suppose you also want to email a site administrator each time a site update is
 made. To do that, you create a new class::
 
-    // src/Updates/SiteUpdateManager.php
-    namespace App\Updates;
+    // src/Service/SiteUpdateManager.php
+    namespace App\Service;
 
     use App\Service\MessageGenerator;
     use Symfony\Component\Mailer\MailerInterface;
@@ -309,7 +315,7 @@ made. To do that, you create a new class::
             $this->mailer = $mailer;
         }
 
-        public function notifyOfSiteUpdate()
+        public function notifyOfSiteUpdate(): bool
         {
             $happyMessage = $this->messageGenerator->getHappyMessage();
 
@@ -322,6 +328,8 @@ made. To do that, you create a new class::
             $this->mailer->send($email);
 
             // ...
+
+            return true;
         }
     }
 
@@ -334,7 +342,7 @@ you can type-hint the new ``SiteUpdateManager`` class and use it::
     namespace App\Controller;
     
     // ...
-    use App\Updates\SiteUpdateManager;
+    use App\Service\SiteUpdateManager;
 
     public function new(SiteUpdateManager $siteUpdateManager)
     {
@@ -361,29 +369,29 @@ example, suppose you want to make the admin email configurable:
 
 .. code-block:: diff
 
-    // src/Updates/SiteUpdateManager.php
+    // src/Service/SiteUpdateManager.php
     // ...
 
     class SiteUpdateManager
     {
         // ...
     +    private $adminEmail;
 
-    -    public function __construct(MessageGenerator $messageGenerator, \Swift_Mailer $mailer)
-    +    public function __construct(MessageGenerator $messageGenerator, \Swift_Mailer $mailer, $adminEmail)
+    -    public function __construct(MessageGenerator $messageGenerator, MailerInterface $mailer)
+    +    public function __construct(MessageGenerator $messageGenerator, MailerInterface $mailer, $adminEmail)
         {
             // ...
     +        $this->adminEmail = $adminEmail;
         }
 
-        public function notifyOfSiteUpdate()
+        public function notifyOfSiteUpdate(): bool
         {
             // ...
 
-            $message = \Swift_Message::newInstance()
+            $email = (new Email())
                 // ...
-    -            ->setTo('manager@example.com')
-    +            ->setTo($this->adminEmail)
+    -            ->to('manager@example.com')
+    +            ->to($this->adminEmail)
                 // ...
             ;
             // ...
@@ -392,7 +400,7 @@ example, suppose you want to make the admin email configurable:
 
 If you make this change and refresh, you'll see an error:
 
-    Cannot autowire service "App\Updates\SiteUpdateManager": argument "$adminEmail"
+    Cannot autowire service "App\Service\SiteUpdateManager": argument "$adminEmail"
     of method "__construct()" must have a type-hint or be given a value explicitly.
 
 That makes sense! There is no way that the container knows what value you want to
@@ -412,7 +420,7 @@ pass here. No problem! In your configuration, you can explicitly set this argume
                 exclude: '../src/{DependencyInjection,Entity,Migrations,Tests,Kernel.php}'
 
             # explicitly configure the service
-            App\Updates\SiteUpdateManager:
+            App\Service\SiteUpdateManager:
                 arguments:
                     $adminEmail: 'manager@example.com'
 
@@ -436,7 +444,7 @@ pass here. No problem! In your configuration, you can explicitly set this argume
                 />
 
                 <!-- Explicitly configure the service -->
-                <service id="App\Updates\SiteUpdateManager">
+                <service id="App\Service\SiteUpdateManager">
                     <argument key="$adminEmail">manager@example.com</argument>
                 </service>
             </services>
@@ -447,7 +455,7 @@ pass here. No problem! In your configuration, you can explicitly set this argume
         // config/services.php
         namespace Symfony\Component\DependencyInjection\Loader\Configurator;
 
-        use App\Updates\SiteUpdateManager;
+        use App\Service\SiteUpdateManager;
 
         return function(ContainerConfigurator $configurator) {
             // ...
@@ -877,7 +885,7 @@ But, if you *do* need to make a service public, override the ``public`` setting:
             # ... same code as before
 
             # explicitly configure the service
-            Acme\PublicService:
+            App\Service\PublicService:
                 public: true
 
     .. code-block:: xml
@@ -893,7 +901,7 @@ But, if you *do* need to make a service public, override the ``public`` setting:
                 <!-- ... same code as before -->
 
                 <!-- Explicitly configure the service -->
-                <service id="Acme\PublicService" public="true"></service>
+                <service id="App\Service\PublicService" public="true"></service>
             </services>
         </container>
 
@@ -902,13 +910,13 @@ But, if you *do* need to make a service public, override the ``public`` setting:
         // config/services.php
         namespace Symfony\Component\DependencyInjection\Loader\Configurator;
 
-        use Acme\PublicService;
+        use App\Service\PublicService;
 
         return function(ContainerConfigurator $configurator) {
             // ... same as code before
 
             // explicitly configure the service
-            $services->set(PublicService::class)
+            $services->set(Service\PublicService::class)
                 ->public()
             ;
         };
@@ -1087,7 +1095,7 @@ admin email. In this case, each needs to have a unique service id:
 
             # this is the service's id
             site_update_manager.superadmin:
-                class: App\Updates\SiteUpdateManager
+                class: App\Service\SiteUpdateManager
                 # you CAN still use autowiring: we just want to show what it looks like without
                 autowire: false
                 # manually wire all arguments
@@ -1097,7 +1105,7 @@ admin email. In this case, each needs to have a unique service id:
                     - 'superadmin@example.com'
 
             site_update_manager.normal_users:
-                class: App\Updates\SiteUpdateManager
+                class: App\Service\SiteUpdateManager
                 autowire: false
                 arguments:
                     - '@App\Service\MessageGenerator'
@@ -1106,7 +1114,7 @@ admin email. In this case, each needs to have a unique service id:
 
             # Create an alias, so that - by default - if you type-hint SiteUpdateManager,
             # the site_update_manager.superadmin will be used
-            App\Updates\SiteUpdateManager: '@site_update_manager.superadmin'
+            App\Service\SiteUpdateManager: '@site_update_manager.superadmin'
 
     .. code-block:: xml
 
@@ -1120,19 +1128,19 @@ admin email. In this case, each needs to have a unique service id:
             <services>
                 <!-- ... -->
 
-                <service id="site_update_manager.superadmin" class="App\Updates\SiteUpdateManager" autowire="false">
+                <service id="site_update_manager.superadmin" class="App\Service\SiteUpdateManager" autowire="false">
                     <argument type="service" id="App\Service\MessageGenerator"/>
                     <argument type="service" id="mailer"/>
                     <argument>superadmin@example.com</argument>
                 </service>
 
-                <service id="site_update_manager.normal_users" class="App\Updates\SiteUpdateManager" autowire="false">
+                <service id="site_update_manager.normal_users" class="App\Service\SiteUpdateManager" autowire="false">
                     <argument type="service" id="App\Service\MessageGenerator"/>
                     <argument type="service" id="mailer"/>
                     <argument>contact@example.com</argument>
                 </service>
 
-                <service id="App\Updates\SiteUpdateManager" alias="site_update_manager.superadmin"/>
+                <service id="App\Service\SiteUpdateManager" alias="site_update_manager.superadmin"/>
             </services>
         </container>
 
@@ -1142,7 +1150,7 @@ admin email. In this case, each needs to have a unique service id:
         namespace Symfony\Component\DependencyInjection\Loader\Configurator;
 
         use App\Service\MessageGenerator;
-        use App\Updates\SiteUpdateManager;
+        use App\Service\SiteUpdateManager;
 
         return function(ContainerConfigurator $configurator) {
             // ...

testing.rst

@@ -599,7 +599,7 @@ it via that alias:
         namespace Symfony\Component\DependencyInjection\Loader\Configurator;
 
         use App\Service\MessageGenerator;
-        use App\Updates\SiteUpdateManager;
+        use App\Service\SiteUpdateManager;
 
         return function(ContainerConfigurator $configurator) {
             // ...