feature symfony#24530 [Form] simplify the form type extension registration (xabbuh)

This PR was merged into the 4.2-dev branch.

Discussion
----------

[Form] simplify the form type extension registration

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | symfony#22833, symfony#27906
| License       | MIT
| Doc PR        |

Commits
-------

6a1d4c5 simplify the form type extension registration

Author: fabpot

UPGRADE-4.2.md

@@ -55,9 +55,38 @@ Finder
 Form
 ----
 
+ * The `getExtendedType()` method of the `FormTypeExtensionInterface` is deprecated and will be removed in 5.0. Type
+   extensions must implement the static `getExtendedTypes()` method instead and return an iterable of extended types.
+
+   Before:
+
+   ```php
+   class FooTypeExtension extends AbstractTypeExtension
+   {
+       public function getExtendedType()
+       {
+           return FormType::class;
+       }
+
+       // ...
+   }
+   ```
+
+   After:
+
+   ```php
+   class FooTypeExtension extends AbstractTypeExtension
+   {
+       public static function getExtendedTypes(): iterable
+       {
+           return array(FormType::class);
+       }
+
+       // ...
+   }
+   ```
  * The `scale` option of the `IntegerType` is deprecated.
  * The `$scale` argument of the `IntegerToLocalizedStringTransformer` is deprecated.
-
  * Deprecated calling `FormRenderer::searchAndRenderBlock` for fields which were already rendered.
    Instead of expecting such calls to return empty strings, check if the field has already been rendered.
 

UPGRADE-5.0.md

@@ -72,6 +72,36 @@ Finder
 Form
 ----
 
+ * The `getExtendedType()` method was removed from the `FormTypeExtensionInterface`. It is replaced by the the static
+   `getExtendedTypes()` method which must return an iterable of extended types.
+
+   Before:
+
+   ```php
+   class FooTypeExtension extends AbstractTypeExtension
+   {
+       public function getExtendedType()
+       {
+           return FormType::class;
+       }
+
+       // ...
+   }
+   ```
+
+   After:
+
+   ```php
+   class FooTypeExtension extends AbstractTypeExtension
+   {
+       public static function getExtendedTypes(): iterable
+       {
+           return array(FormType::class);
+       }
+
+       // ...
+   }
+   ```
  * The `scale` option was removed from the `IntegerType`.
  * The `$scale` argument of the `IntegerToLocalizedStringTransformer` was removed.
 

src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php

@@ -52,6 +52,7 @@
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 use Symfony\Component\ExpressionLanguage\ExpressionLanguage;
 use Symfony\Component\Finder\Finder;
+use Symfony\Component\Form\FormTypeExtensionInterface;
 use Symfony\Component\Form\FormTypeGuesserInterface;
 use Symfony\Component\Form\FormTypeInterface;
 use Symfony\Component\HttpKernel\CacheClearer\CacheClearerInterface;
@@ -325,6 +326,8 @@ public function load(array $configs, ContainerBuilder $container)
             ->addTag('form.type');
         $container->registerForAutoconfiguration(FormTypeGuesserInterface::class)
             ->addTag('form.type_guesser');
+        $container->registerForAutoconfiguration(FormTypeExtensionInterface::class)
+            ->addTag('form.type_extension');
         $container->registerForAutoconfiguration(CacheClearerInterface::class)
             ->addTag('kernel.cache_clearer');
         $container->registerForAutoconfiguration(CacheWarmerInterface::class)

src/Symfony/Bundle/FrameworkBundle/Resources/config/form.xml

@@ -74,7 +74,7 @@
         <!-- FormTypeHttpFoundationExtension -->
         <service id="form.type_extension.form.http_foundation" class="Symfony\Component\Form\Extension\HttpFoundation\Type\FormTypeHttpFoundationExtension">
             <argument type="service" id="form.type_extension.form.request_handler" />
-            <tag name="form.type_extension" extended-type="Symfony\Component\Form\Extension\Core\Type\FormType" />
+            <tag name="form.type_extension" />
         </service>
 
         <!-- HttpFoundationRequestHandler -->
@@ -92,13 +92,13 @@
             <argument type="service" id="validator" />
         </service>
         <service id="form.type_extension.repeated.validator" class="Symfony\Component\Form\Extension\Validator\Type\RepeatedTypeValidatorExtension">
-            <tag name="form.type_extension" extended-type="Symfony\Component\Form\Extension\Core\Type\RepeatedType" />
+            <tag name="form.type_extension" />
         </service>
         <service id="form.type_extension.submit.validator" class="Symfony\Component\Form\Extension\Validator\Type\SubmitTypeValidatorExtension">
             <tag name="form.type_extension" extended-type="Symfony\Component\Form\Extension\Core\Type\SubmitType" />
         </service>
         <service id="form.type_extension.upload.validator" class="Symfony\Component\Form\Extension\Validator\Type\UploadValidatorExtension">
-            <tag name="form.type_extension" extended-type="Symfony\Component\Form\Extension\Core\Type\FormType" />
+            <tag name="form.type_extension" />
             <argument type="service" id="translator"/>
             <argument type="string">%validator.translation_domain%</argument>
         </service>

src/Symfony/Bundle/FrameworkBundle/Resources/config/form_csrf.xml

@@ -8,7 +8,7 @@
         <defaults public="false" />
 
         <service id="form.type_extension.csrf" class="Symfony\Component\Form\Extension\Csrf\Type\FormTypeCsrfExtension">
-            <tag name="form.type_extension" extended-type="Symfony\Component\Form\Extension\Core\Type\FormType" />
+            <tag name="form.type_extension" />
             <argument type="service" id="security.csrf.token_manager" />
             <argument>%form.type_extension.csrf.enabled%</argument>
             <argument>%form.type_extension.csrf.field_name%</argument>

src/Symfony/Bundle/FrameworkBundle/Resources/config/form_debug.xml

@@ -16,7 +16,7 @@
 
         <!-- DataCollectorTypeExtension -->
         <service id="form.type_extension.form.data_collector" class="Symfony\Component\Form\Extension\DataCollector\Type\DataCollectorTypeExtension">
-            <tag name="form.type_extension" extended-type="Symfony\Component\Form\Extension\Core\Type\FormType" />
+            <tag name="form.type_extension" />
             <argument type="service" id="data_collector.form" />
         </service>
 

src/Symfony/Bundle/FrameworkBundle/composer.json

@@ -39,7 +39,7 @@
         "symfony/dom-crawler": "~3.4|~4.0",
         "symfony/polyfill-intl-icu": "~1.0",
         "symfony/security": "~3.4|~4.0",
-        "symfony/form": "^4.1",
+        "symfony/form": "^4.2",
         "symfony/expression-language": "~3.4|~4.0",
         "symfony/messenger": "^4.2",
         "symfony/process": "~3.4|~4.0",
@@ -66,7 +66,7 @@
         "phpunit/phpunit": "<4.8.35|<5.4.3,>=5.0",
         "symfony/asset": "<3.4",
         "symfony/console": "<3.4",
-        "symfony/form": "<4.1",
+        "symfony/form": "<4.2",
         "symfony/messenger": "<4.2",
         "symfony/property-info": "<3.4",
         "symfony/serializer": "<4.1",

src/Symfony/Component/Form/AbstractExtension.php

@@ -175,9 +175,21 @@ private function initTypeExtensions()
                 throw new UnexpectedTypeException($extension, 'Symfony\Component\Form\FormTypeExtensionInterface');
             }
 
-            $type = $extension->getExtendedType();
+            if (method_exists($extension, 'getExtendedTypes')) {
+                $extendedTypes = array();
 
-            $this->typeExtensions[$type][] = $extension;
+                foreach ($extension::getExtendedTypes() as $extendedType) {
+                    $extendedTypes[] = $extendedType;
+                }
+            } else {
+                @trigger_error(sprintf('Not implementing the static getExtendedTypes() method in %s when implementing the %s is deprecated since Symfony 4.2. The method will be added to the interface in 5.0.', \get_class($extension), FormTypeExtensionInterface::class), E_USER_DEPRECATED);
+
+                $extendedTypes = array($extension->getExtendedType());
+            }
+
+            foreach ($extendedTypes as $extendedType) {
+                $this->typeExtensions[$extendedType][] = $extension;
+            }
         }
     }
 

src/Symfony/Component/Form/AbstractTypeExtension.php

@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Form;
 
+use Symfony\Component\Form\Exception\LogicException;
 use Symfony\Component\OptionsResolver\OptionsResolver;
 
 /**
@@ -45,4 +46,22 @@ public function finishView(FormView $view, FormInterface $form, array $options)
     public function configureOptions(OptionsResolver $resolver)
     {
     }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @deprecated since Symfony 4.2, use getExtendedTypes() instead.
+     */
+    public function getExtendedType()
+    {
+        if (!method_exists($this, 'getExtendedTypes')) {
+            throw new LogicException(sprintf('You need to implement the static getExtendedTypes() method when implementing the %s in %s.', FormTypeExtensionInterface::class, static::class));
+        }
+
+        @trigger_error(sprintf('The %s::getExtendedType() method is deprecated since Symfony 4.2 and will be removed in 5.0. Use getExtendedTypes() instead.', \get_class($this)), E_USER_DEPRECATED);
+
+        foreach (static::getExtendedTypes() as $extendedType) {
+            return $extendedType;
+        }
+    }
 }

src/Symfony/Component/Form/CHANGELOG.md

@@ -4,6 +4,36 @@ CHANGELOG
 4.2.0
 -----
 
+ * The `getExtendedType()` method of the `FormTypeExtensionInterface` is deprecated and will be removed in 5.0. Type
+   extensions must implement the static `getExtendedTypes()` method instead and return an iterable of extended types.
+
+   Before:
+
+   ```php
+   class FooTypeExtension extends AbstractTypeExtension
+   {
+       public function getExtendedType()
+       {
+           return FormType::class;
+       }
+
+       // ...
+   }
+   ```
+
+   After:
+
+   ```php
+   class FooTypeExtension extends AbstractTypeExtension
+   {
+       public static function getExtendedTypes(): iterable
+       {
+           return array(FormType::class);
+       }
+
+       // ...
+   }
+   ```
  * deprecated the `$scale` argument of the `IntegerToLocalizedStringTransformer`
  * added `Symfony\Component\Form\ClearableErrorsInterface`
  * deprecated calling `FormRenderer::searchAndRenderBlock` for fields which were already rendered