Multiplier generics

composer.json

@@ -18,6 +18,7 @@
 		"nette/utils": "<2.3.0"
 	},
 	"require-dev": {
+		"nette/application": "^3.0",
 		"nette/forms": "^3.0",
 		"nette/utils": "^2.3.0 || ^3.0.0",
 		"nikic/php-parser": "^4.13.2",

extension.neon

@@ -7,6 +7,7 @@ parameters:
 	stubFiles:
 		- stubs/Application/Routers/RouteList.stub
 		- stubs/Application/UI/Component.stub
+		- stubs/Application/UI/Multiplier.stub
 		- stubs/ComponentModel/Component.stub
 		- stubs/ComponentModel/Container.stub
 		- stubs/ComponentModel/IComponent.stub
@@ -31,6 +32,9 @@ parameters:
 		- Nette\Http\SessionSection
 		- Nette\Security\Identity
 		- Nette\Security\SimpleIdentity
+	featureToggles:
+		skipCheckGenericClasses:
+			- Nette\Application\UI\Multiplier
 	earlyTerminatingMethodCalls:
 		Nette\Application\UI\Component:
 			- error

stubs/Application/UI/Multiplier.stub

@@ -0,0 +1,19 @@
+<?php
+
+namespace Nette\Application\UI;
+
+/**
+ * @template T of \Nette\ComponentModel\IComponent
+ */
+final class Multiplier extends Component
+{
+    /**
+     * @param callable(string, self<T>) : T $factory
+     */
+    public function __construct(callable $factory);
+
+    /**
+     * @return T
+     */
+    protected function createComponent(string $name): \Nette\ComponentModel\IComponent;
+}

tests/Type/Nette/MultiplierTest.php

@@ -0,0 +1,36 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\Nette;
+
+use PHPStan\Testing\TypeInferenceTestCase;
+
+class MultiplierTest extends TypeInferenceTestCase
+{
+
+	/** @return iterable<mixed> */
+	public function dataFileAsserts(): iterable
+	{
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/multiplier.php');
+	}
+
+	/**
+	 * @dataProvider dataFileAsserts
+	 * @param mixed ...$args
+	 */
+	public function testFileAsserts(
+		string $assertType,
+		string $file,
+		...$args
+	): void
+	{
+		$this->assertFileAsserts($assertType, $file, ...$args);
+	}
+
+	public static function getAdditionalConfigFiles(): array
+	{
+		return [
+			__DIR__ . '/../../../extension.neon',
+		];
+	}
+
+}

tests/Type/Nette/data/multiplier.php

@@ -0,0 +1,17 @@
+<?php declare(strict_types = 1);
+
+use Nette\Application\UI\Form;
+use Nette\Application\UI\Multiplier;
+
+use function PHPStan\Testing\assertType;
+
+/** @var Multiplier<Form> $multiplier */
+$multiplier = new Multiplier(function (string $name): Form {
+	return new Form();
+});
+
+assertType('Nette\Application\UI\Multiplier<Nette\Application\UI\Form>', $multiplier);
+
+$form = $multiplier->createComponent('foo');
+
+assertType(Form::class, $form);