Support for Request::getSession type specifying.

Author: pplotka

extension.neon

@@ -59,6 +59,11 @@ services:
 		factory: PHPStan\Type\Symfony\RequestDynamicReturnTypeExtension
 		tags: [phpstan.broker.dynamicMethodReturnTypeExtension]
 
+	# Request::getSession() type specification
+	-
+		factory: PHPStan\Type\Symfony\RequestTypeSpecifyingExtension
+		tags: [phpstan.typeSpecifier.methodTypeSpecifyingExtension]
+
 	# HeaderBag::get() return type
 	-
 		factory: PHPStan\Type\Symfony\HeaderBagDynamicReturnTypeExtension

src/Type/Symfony/RequestTypeSpecifyingExtension.php

@@ -0,0 +1,59 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\Symfony;
+
+use PhpParser\Node\Expr\MethodCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Analyser\SpecifiedTypes;
+use PHPStan\Analyser\TypeSpecifier;
+use PHPStan\Analyser\TypeSpecifierAwareExtension;
+use PHPStan\Analyser\TypeSpecifierContext;
+use PHPStan\Broker\Broker;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Reflection\ParametersAcceptorSelector;
+use PHPStan\Type\MethodTypeSpecifyingExtension;
+use PHPStan\Type\TypeCombinator;
+use Symfony\Component\HttpFoundation\Request;
+
+final class RequestTypeSpecifyingExtension implements MethodTypeSpecifyingExtension, TypeSpecifierAwareExtension
+{
+
+	/** @var Broker */
+	private $broker;
+
+	/** @var TypeSpecifier */
+	private $typeSpecifier;
+
+	public function __construct(Broker $broker)
+	{
+		$this->broker = $broker;
+	}
+
+	public function getClass(): string
+	{
+		return Request::class;
+	}
+
+	public function isMethodSupported(MethodReflection $methodReflection, MethodCall $node, TypeSpecifierContext $context): bool
+	{
+		return $methodReflection->getName() === 'hasSession' && !$context->null();
+	}
+
+	public function specifyTypes(MethodReflection $methodReflection, MethodCall $node, Scope $scope, TypeSpecifierContext $context): SpecifiedTypes
+	{
+		$classReflection = $this->broker->getClass(Request::class);
+		$methodVariants = $classReflection->getNativeMethod('getSession')->getVariants();
+
+		return $this->typeSpecifier->create(
+			new MethodCall($node->var, 'getSession'),
+			TypeCombinator::removeNull(ParametersAcceptorSelector::selectSingle($methodVariants)->getReturnType()),
+			$context
+		);
+	}
+
+	public function setTypeSpecifier(TypeSpecifier $typeSpecifier): void
+	{
+		$this->typeSpecifier = $typeSpecifier;
+	}
+
+}