Return type extension for Controller::createForm

composer.json

@@ -32,7 +32,8 @@
     "satooshi/php-coveralls": "^1.0",
     "slevomat/coding-standard": "^4.5.2",
     "phpstan/phpstan-phpunit": "^0.10",
-    "symfony/framework-bundle": "^3.0 || ^4.0"
+    "symfony/framework-bundle": "^3.0 || ^4.0",
+    "symfony/form": "^3.0 || ^4.0"
   },
   "conflict": {
     "symfony/framework-bundle": "<3.0"

src/Type/Symfony/ControllerDynamicReturnTypeExtension.php

@@ -5,9 +5,12 @@
 use PhpParser\Node\Expr\MethodCall;
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\MethodReflection;
+use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\Symfony\ServiceMap;
 use PHPStan\Type\DynamicMethodReturnTypeExtension;
+use PHPStan\Type\ObjectType;
 use PHPStan\Type\Type;
+use PHPStan\Type\TypeUtils;
 
 final class ControllerDynamicReturnTypeExtension implements DynamicMethodReturnTypeExtension
 {
@@ -27,7 +30,7 @@ public function getClass(): string
 
 	public function isMethodSupported(MethodReflection $methodReflection): bool
 	{
-		return in_array($methodReflection->getName(), ['get', 'has'], true);
+		return in_array($methodReflection->getName(), ['get', 'has', 'createForm'], true);
 	}
 
 	public function getTypeFromMethodCall(
@@ -41,8 +44,34 @@ public function getTypeFromMethodCall(
 				return Helper::getGetTypeFromMethodCall($methodReflection, $methodCall, $scope, $this->serviceMap);
 			case 'has':
 				return Helper::getHasTypeFromMethodCall($methodReflection, $methodCall, $scope, $this->serviceMap);
+			case 'createForm':
+				return $this->getCreateFormTypeFromMethodCall($methodReflection, $methodCall, $scope);
 		}
 		throw new \PHPStan\ShouldNotHappenException();
 	}
 
+	private function getCreateFormTypeFromMethodCall(
+		MethodReflection $methodReflection,
+		MethodCall $methodCall,
+		Scope $scope
+	): Type
+	{
+		$returnType = ParametersAcceptorSelector::selectSingle($methodReflection->getVariants())->getReturnType();
+		if (!isset($methodCall->args[0])) {
+			return $returnType;
+		}
+
+		$types = TypeUtils::getConstantStrings($scope->getType($methodCall->args[0]->value));
+		if (count($types) !== 1) {
+			return $returnType;
+		}
+
+		$formType = new ObjectType($types[0]->getValue());
+		if (!(new ObjectType('Symfony\Component\Form\FormTypeInterface'))->isSuperTypeOf($formType)->yes()) {
+			return $returnType;
+		}
+
+		return $formType;
+	}
+
 }

tests/Symfony/data/ExampleFormType.php

@@ -0,0 +1,10 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Symfony;
+
+use Symfony\Component\Form\AbstractType;
+
+final class ExampleFormType extends AbstractType
+{
+
+}

tests/Type/Symfony/ControllerDynamicReturnTypeExtensionTest.php

@@ -7,6 +7,8 @@
 use PhpParser\Node\Expr\MethodCall;
 use PhpParser\Node\Scalar\String_;
 use PHPStan\Analyser\Scope;
+use PHPStan\Broker\Broker;
+use PHPStan\Reflection\ClassReflection;
 use PHPStan\Reflection\MethodReflection;
 use PHPStan\Reflection\ParametersAcceptor;
 use PHPStan\Symfony\ServiceMap;
@@ -39,11 +41,19 @@ public function testIsMethodSupported(): void
 		$methodGet = $this->createMock(MethodReflection::class);
 		$methodGet->expects(self::once())->method('getName')->willReturn('get');
 
+		$methodHas = $this->createMock(MethodReflection::class);
+		$methodHas->expects(self::once())->method('getName')->willReturn('has');
+
+		$methodCreateForm = $this->createMock(MethodReflection::class);
+		$methodCreateForm->expects(self::once())->method('getName')->willReturn('createForm');
+
 		$methodFoo = $this->createMock(MethodReflection::class);
 		$methodFoo->expects(self::once())->method('getName')->willReturn('foo');
 
 		$extension = new ControllerDynamicReturnTypeExtension(new ServiceMap(__DIR__ . '/../../Symfony/data/container.xml'));
 		self::assertTrue($extension->isMethodSupported($methodGet));
+		self::assertTrue($extension->isMethodSupported($methodHas));
+		self::assertTrue($extension->isMethodSupported($methodCreateForm));
 		self::assertFalse($extension->isMethodSupported($methodFoo));
 	}
 
@@ -104,4 +114,43 @@ public function getTypeFromMethodCallProvider(): array
 		];
 	}
 
+	public function testCreateContainer(): void
+	{
+		$parametersAcceptorFound = $this->createMock(ParametersAcceptor::class);
+		$parametersAcceptorFound->expects(self::once())->method('getReturnType')->willReturn(new ObjectType('Symfony\Component\Form\FormInterface'));
+
+		$methodReflection = $this->createMock(MethodReflection::class);
+		$methodReflection->expects(self::once())->method('getName')->willReturn('createForm');
+		$methodReflection->expects(self::once())->method('getVariants')->willReturn([$parametersAcceptorFound]);
+
+		$methodCall = new MethodCall($this->createMock(Expr::class), 'createForm', [new Arg(new String_('PHPStan\Symfony\ExampleFormType'))]);
+
+		$scope = $this->createMock(Scope::class);
+		$scope->expects(self::once())->method('getType')->willReturn(new ConstantStringType('PHPStan\Symfony\ExampleFormType'));
+
+		$thisClassReflection = $this->createMock(ClassReflection::class);
+		$thisClassReflection->expects(self::once())->method('getName')->willReturn('Symfony\Component\Form\FormInterface');
+
+		$thatClassReflection = $this->createMock(ClassReflection::class);
+		$thatClassReflection->expects(self::once())->method('getName')->willReturn('PHPStan\Symfony\ExampleFormType');
+		$thatClassReflection->expects(self::once())->method('isSubclassOf')->willReturn(true);
+
+		$broker = $this->createMock(Broker::class);
+		$broker->expects(self::at(0))->method('hasClass')->willReturn(true);
+		$broker->expects(self::at(1))->method('hasClass')->willReturn(true);
+		$broker->expects(self::at(2))->method('getClass')->willReturn($thisClassReflection);
+		$broker->expects(self::at(3))->method('getClass')->willReturn($thatClassReflection);
+		Broker::registerInstance($broker);
+
+		$extension = new ControllerDynamicReturnTypeExtension(new ServiceMap(__DIR__ . '/../../Symfony/data/container.xml'));
+		$type = $extension->getTypeFromMethodCall(
+			$methodReflection,
+			$methodCall,
+			$scope
+		);
+
+		self::assertInstanceOf(ObjectType::class, $type);
+		self::assertSame('PHPStan\Symfony\ExampleFormType', $type->getClassName());
+	}
+
 }