Add stub for AbstractController::createForm()

extension.neon

@@ -27,6 +27,7 @@ parameters:
 		- stubs/Psr/Cache/CacheException.stub
 		- stubs/Psr/Cache/CacheItemInterface.stub
 		- stubs/Psr/Cache/InvalidArgumentException.stub
+		- stubs/Symfony/Bundle/FrameworkBundle/Controller/AbstractController.stub
 		- stubs/Symfony/Bundle/FrameworkBundle/KernelBrowser.stub
 		- stubs/Symfony/Bundle/FrameworkBundle/Test/KernelTestCase.stub
 		- stubs/Symfony/Bundle/FrameworkBundle/Test/TestContainer.stub
@@ -103,6 +104,7 @@ parameters:
 		- stubs/Symfony/Contracts/Cache/CacheInterface.stub
 		- stubs/Symfony/Contracts/Cache/CallbackInterface.stub
 		- stubs/Symfony/Contracts/Cache/ItemInterface.stub
+		- stubs/Symfony/Contracts/Service/ServiceSubscriberInterface.stub
 		- stubs/Twig/Node/Node.stub
 
 parametersSchema:

stubs/Symfony/Bundle/FrameworkBundle/Controller/AbstractController.stub

@@ -0,0 +1,24 @@
+<?php
+
+namespace Symfony\Bundle\FrameworkBundle\Controller;
+
+use Symfony\Component\Form\FormInterface;
+use Symfony\Component\Form\FormTypeInterface;
+use Symfony\Contracts\Service\ServiceSubscriberInterface;
+
+abstract class AbstractController implements ServiceSubscriberInterface
+{
+	/**
+	 * @template TFormType of FormTypeInterface<TData>
+	 * @template TData
+	 *
+	 * @param class-string<TFormType> $type
+	 * @param TData                   $data
+	 * @param array<string, mixed>    $options
+	 *
+	 * @phpstan-return ($data is null ? FormInterface<null|TData> : FormInterface<TData>)
+	 */
+	protected function createForm(string $type, $data = null, array $options = []): FormInterface
+	{
+	}
+}

stubs/Symfony/Contracts/Service/ServiceSubscriberInterface.stub

@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Contracts\Service;
+
+interface ServiceSubscriberInterface
+{
+}

tests/Type/Symfony/data/form_data_type.php

@@ -2,6 +2,7 @@
 
 namespace GenericFormDataType;
 
+use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
 use Symfony\Component\Form\AbstractType;
 use Symfony\Component\Form\Extension\Core\Type\NumberType;
 use Symfony\Component\Form\Extension\Core\Type\TextType;
@@ -73,3 +74,20 @@ public function doSomethingNullable(): void
 	}
 
 }
+
+class FormController extends AbstractController
+{
+
+	public function doSomething(): void
+	{
+		$form = $this->createForm(DataClassType::class, new DataClass());
+		assertType('GenericFormDataType\DataClass', $form->getData());
+	}
+
+	public function doSomethingNullable(): void
+	{
+		$form = $this->createForm(DataClassType::class);
+		assertType('GenericFormDataType\DataClass|null', $form->getData());
+	}
+
+}