Type-specifying extension for ReflectionClass::isSubclassOf()

Author: ondrejmirtes

conf/config.neon

@@ -1024,6 +1024,11 @@ services:
 tags:
 - phpstan.broker.dynamicFunctionReturnTypeExtension
 
+-
+class: PHPStan\Type\Php\ReflectionClassIsSubclassOfTypeSpecifyingExtension
+tags:
+- phpstan.typeSpecifier.methodTypeSpecifyingExtension
+
 -
 class: PHPStan\Type\Php\ReplaceFunctionsDynamicReturnTypeExtension
 tags:

src/Testing/TestCase.php

@@ -628,8 +628,8 @@ public function createTypeSpecifier(
 $printer,
 $reflectionProvider,
 self::getContainer()->getServicesByTag(TypeSpecifierFactory::FUNCTION_TYPE_SPECIFYING_EXTENSION_TAG),
-$methodTypeSpecifyingExtensions,
-$staticMethodTypeSpecifyingExtensions
+array_merge($methodTypeSpecifyingExtensions, self::getContainer()->getServicesByTag(TypeSpecifierFactory::METHOD_TYPE_SPECIFYING_EXTENSION_TAG)),
+array_merge($staticMethodTypeSpecifyingExtensions, self::getContainer()->getServicesByTag(TypeSpecifierFactory::STATIC_METHOD_TYPE_SPECIFYING_EXTENSION_TAG)),
 );
 }
 

src/Type/Php/ReflectionClassIsSubclassOfTypeSpecifyingExtension.php

@@ -0,0 +1,55 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\Php;
+
+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\Reflection\MethodReflection;
+use PHPStan\Type\Constant\ConstantStringType;
+use PHPStan\Type\Generic\GenericObjectType;
+use PHPStan\Type\MethodTypeSpecifyingExtension;
+use PHPStan\Type\ObjectType;
+
+class ReflectionClassIsSubclassOfTypeSpecifyingExtension implements MethodTypeSpecifyingExtension, TypeSpecifierAwareExtension
+{
+
+private TypeSpecifier $typeSpecifier;
+
+public function setTypeSpecifier(TypeSpecifier $typeSpecifier): void
+{
+$this->typeSpecifier = $typeSpecifier;
+}
+
+public function getClass(): string
+{
+return \ReflectionClass::class;
+}
+
+public function isMethodSupported(MethodReflection $methodReflection, MethodCall $node, TypeSpecifierContext $context): bool
+{
+return $methodReflection->getName() === 'isSubclassOf'
+&& isset($node->args[0])
+&& $context->true();
+}
+
+public function specifyTypes(MethodReflection $methodReflection, MethodCall $node, Scope $scope, TypeSpecifierContext $context): SpecifiedTypes
+{
+$valueType = $scope->getType($node->args[0]->value);
+if (!$valueType instanceof ConstantStringType) {
+return new SpecifiedTypes([], []);
+}
+
+return $this->typeSpecifier->create(
+$node->var,
+new GenericObjectType(\ReflectionClass::class, [
+new ObjectType($valueType->getValue()),
+]),
+$context
+);
+}
+
+}

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -10892,6 +10892,11 @@ public function dataBug4573(): array
 return $this->gatherAssertTypes(__DIR__ . '/data/bug-4573.php');
 }
 
+public function dataBug4577(): array
+{
+return $this->gatherAssertTypes(__DIR__ . '/data/bug-4577.php');
+}
+
 /**
  * @param string $file
  * @return array<string, mixed[]>
@@ -11132,6 +11137,7 @@ private function gatherAssertTypes(string $file): array
  * @dataProvider dataBug2112
  * @dataProvider dataArrayMapClosure
  * @dataProvider dataBug4573
+ * @dataProvider dataBug4577
  * @param string $assertType
  * @param string $file
  * @param mixed ...$args

tests/PHPStan/Analyser/data/bug-4577.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace Bug4577;
+
+use function PHPStan\Analyser\assertType;
+
+class Test
+{
+
+public function test(\ReflectionClass $refClass): void
+{
+if ($refClass->isSubclassOf(Test::class)) {
+$instance = $refClass->newInstance();
+assertType(Test::class, $instance);
+}
+}
+
+}