minor #11765 [Forms] Reworded the article about creating custom form types (javiereguiluz)

This PR was squashed before being merged into the 4.2 branch (closes #11765).

Discussion
----------

[Forms] Reworded the article about creating custom form types

The new contents are completely different from the original ones, so you may prefer to review this by reading the rendered result: https://github.com/javiereguiluz/symfony-docs/blob/7bbd69e56621f450f5ca0e2fd78e397e0abbf947/form/create_custom_field_type.rst

Commits
-------

ac08120 [Forms] Reworded the article about creating custom form types

Author: javiereguiluz

_images/form/form-custom-type-postal-address-fragment-names.svg

@@ -60,8 +60,9 @@ For more information on what those methods do, see the
 Registering your Form Type Extension as a Service
 -------------------------------------------------
 
-Form type extensions must be registered as services and :doc:`tagged </service_container/tags>`
-with the ``form.type_extension`` tag. If you're using the
+Form type extensions must be :ref:`registered as services <service-container-creating-service>`
+and :doc:`tagged </service_container/tags>` with the ``form.type_extension`` tag.
+If you're using the
 :ref:`default services.yaml configuration <service-container-services-load-example>`,
 this is already done for you, thanks to :ref:`autoconfiguration <services-autoconfigure>`.
 

_images/form/form-custom-type-postal-address.svg

@@ -291,14 +291,13 @@ and type-hint the new class::
         // ...
     }
 
-That's it! As long as you're using :ref:`autowire <services-autowire>` and
-:ref:`autoconfigure <services-autoconfigure>`, Symfony will automatically
-know to pass your ``TaskType`` an instance of the ``IssueToNumberTransformer``.
-
-.. tip::
-
-    For more information about defining form types as services, read
-    :doc:`register your form type as a service </form/form_dependencies>`.
+That's it! If you're using the
+:ref:`default services.yaml configuration <service-container-services-load-example>`,
+Symfony will automatically know to pass your ``TaskType`` an instance of the
+``IssueToNumberTransformer`` thanks to :ref:`autowire <services-autowire>` and
+:ref:`autoconfigure <services-autoconfigure>`.
+Otherwise, :ref:`register the form class as a service <service-container-creating-service>`
+and :doc:`tag it </service_container/tags>` with the ``form.type`` tag.
 
 Now, you can use your ``TaskType``::
 

_images/sources/form/form-custom-type-postal-address-fragment-names.dia

@@ -326,10 +326,11 @@ security helper to fill in the listener logic::
 Using the Form
 ~~~~~~~~~~~~~~
 
-If you're using :ref:`autowire <services-autowire>` and
-:ref:`autoconfigure <services-autoconfigure>`, your form is ready to be used!
-Otherwise, see :doc:`/form/form_dependencies` to learn how to register your form
-type as a service.
+If you're using the :ref:`default services.yaml configuration <service-container-services-load-example>`,
+your form is ready to be used thanks to :ref:`autowire <services-autowire>` and
+:ref:`autoconfigure <services-autoconfigure>`.
+Otherwise, :ref:`register the form class as a service <service-container-creating-service>`
+and :doc:`tag it </service_container/tags>` with the ``form.type`` tag.
 
 In a controller, create the form like normal::
 

_images/sources/form/form-custom-type-postal-address.dia

@@ -1,144 +1,12 @@
 How to Access Services or Config from Inside a Form
 ===================================================
 
-Sometimes, you may need to access a :doc:`service </service_container>` or other
-configuration from inside of your form class. To do this, you have 2 options:
-
-1) Pass Options to your Form
-----------------------------
-
-The simplest way to pass services or configuration to your form is via form *options*.
-Suppose you need to access the Doctrine entity manager so that you can make a
-query. First, allow (in fact, require) a new ``entity_manager`` option to be
-passed to your form::
-
-    // src/Form/TaskType.php
-    // ...
-
-    class TaskType extends AbstractType
-    {
-        // ...
-
-        public function configureOptions(OptionsResolver $resolver)
-        {
-            // ...
-
-            $resolver->setRequired('entity_manager');
-        }
-    }
-
-Now that you've done this, you *must* pass an ``entity_manager`` option when you
-create your form::
-
-    // src/Controller/DefaultController.php
-    use App\Form\TaskType;
-
-    // ...
-    public function new()
-    {
-        $entityManager = $this->getDoctrine()->getManager();
-
-        $task = ...;
-        $form = $this->createForm(TaskType::class, $task, [
-            'entity_manager' => $entityManager,
-        ]);
-
-        // ...
-    }
-
-Finally, the ``entity_manager`` option is accessible in the ``$options`` argument
-of your ``buildForm()`` method::
-
-    // src/Form/TaskType.php
-    // ...
-
-    class TaskType extends AbstractType
-    {
-        public function buildForm(FormBuilderInterface $builder, array $options)
-        {
-            /** @var \Doctrine\ORM\EntityManager $entityManager */
-            $entityManager = $options['entity_manager'];
-            // ...
-        }
-
-        // ...
-    }
-
-Use this method to pass *anything* to your form.
-
-2) Define your Form as a Service
---------------------------------
-
-Alternatively, you can define your form class as a service. This is a good idea if
-you want to re-use the form in several places - registering it as a service makes
-this easier.
-
-Suppose you need to access the :ref:`EntityManager <doctrine-entity-manager>` object
-so that you can make a query. First, add this as an argument to your form class::
-
-    // src/Form/TaskType.php
-    use Doctrine\ORM\EntityManagerInterface;
-    // ...
-
-    class TaskType extends AbstractType
-    {
-        private $entityManager;
-
-        public function __construct(EntityManagerInterface $entityManager)
-        {
-            $this->entityManager = $entityManager;
-        }
-
-        // ...
-    }
-
-If you're using :ref:`autowire <services-autowire>` and
-:ref:`autoconfigure <services-autoconfigure>`, then you don't need to do *anything*
-else: Symfony will automatically know how to pass the correct ``EntityManager`` object
-to your ``__construct()`` method.
-
-If you are **not using autowire and autoconfigure**, register your form as a service
-manually and tag it with ``form.type``:
-
-.. configuration-block::
-
-    .. code-block:: yaml
-
-        # config/services.yaml
-        services:
-            App\Form\TaskType:
-                arguments: ['@doctrine.orm.entity_manager']
-                tags: [form.type]
-
-    .. code-block:: xml
-
-        <!-- config/services.xml -->
-        <?xml version="1.0" encoding="UTF-8" ?>
-        <container xmlns="http://symfony.com/schema/dic/services"
-            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-            xsi:schemaLocation="http://symfony.com/schema/dic/services
-                https://symfony.com/schema/dic/services/services-1.0.xsd">
-
-            <services>
-                <service id="App\Form\TaskType">
-                    <argument type="service" id="doctrine.orm.entity_manager"/>
-                    <tag name="form.type"/>
-                </service>
-            </services>
-        </container>
-
-    .. code-block:: php
-
-        // config/services.php
-        use App\Form\TaskType;
-        use Symfony\Component\DependencyInjection\Reference;
-
-        $container->register(TaskType::class)
-            ->addArgument(new Reference('doctrine.orm.entity_manager'))
-            ->addTag('form.type')
-        ;
-
-That's it! Your controller - where you create the form - doesn't need to change
-at all: Symfony is smart enough to load the ``TaskType`` from the container.
-
-Read :ref:`form-field-service` for more information.
+The content of this article is no longer relevant because in current Symfony
+versions, form classes are services by default and you can inject services in
+them using the :doc:`service autowiring </service_container/autowiring>` feature.
+
+Read the article about :doc:`creating custom form types </form/create_custom_field_type>`
+to see an example of how to inject the database service into a form type. In the
+same article you can also read about
+:ref:`configuration options for form types <form-type-config-options>`, which is
+another way of passing services to forms.

form/create_custom_field_type.rst

@@ -75,7 +75,11 @@ The point is, you can set ``empty_data`` to the exact "new" object that you want
 .. tip::
 
     In order to pass arguments to the ``BlogType`` constructor, you'll need to
-    :doc:`register it as a service and tag with form.type </form/form_dependencies>`.
+    :ref:`register the form as a service <service-container-creating-service>`
+    and :doc:`tag it </service_container/tags>` with ``form.type``.
+    If you're using the
+    :ref:`default services.yaml configuration <service-container-services-load-example>`,
+    this is already done for you.
 
 .. _forms-empty-data-closure: