Fluent interface method only invalidates its own object by default, not arguments

Author: ondrejmirtes

src/Analyser/MutatingScope.php

@@ -5156,6 +5156,17 @@ public function getMethodReflection(Type $typeWithMethod, string $methodName): ?
 		return $type->getMethod($methodName, $this);
 	}
 
+	/** @api */
+	public function getNakedMethod(Type $typeWithMethod, string $methodName): ?ExtendedMethodReflection
+	{
+		$type = $this->filterTypeWithMethod($typeWithMethod, $methodName);
+		if ($type === null) {
+			return null;
+		}
+
+		return $type->getUnresolvedMethodPrototype($methodName, $this)->getNakedMethod();
+	}
+
 	/**
 	 * @param MethodCall|Node\Expr\StaticCall $methodCall
 	 */

src/Analyser/NodeScopeResolver.php

@@ -118,6 +118,7 @@
 use PHPStan\PhpDoc\Tag\VarTag;
 use PHPStan\Reflection\Assertions;
 use PHPStan\Reflection\ClassReflection;
+use PHPStan\Reflection\ExtendedMethodReflection;
 use PHPStan\Reflection\FunctionReflection;
 use PHPStan\Reflection\InitializerExprTypeResolver;
 use PHPStan\Reflection\MethodReflection;
@@ -160,6 +161,7 @@
 use PHPStan\Type\StaticType;
 use PHPStan\Type\StaticTypeFactory;
 use PHPStan\Type\StringType;
+use PHPStan\Type\ThisType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
 use PHPStan\Type\TypeTraverser;
@@ -2080,7 +2082,7 @@ static function (): void {
 			if ($parametersAcceptor !== null) {
 				$expr = ArgumentsNormalizer::reorderFuncArguments($parametersAcceptor, $expr) ?? $expr;
 			}
-			$result = $this->processArgs($stmt, $functionReflection, $parametersAcceptor, $expr->getArgs(), $scope, $nodeCallback, $context);
+			$result = $this->processArgs($stmt, $functionReflection, null, $parametersAcceptor, $expr->getArgs(), $scope, $nodeCallback, $context);
 			$scope = $result->getScope();
 			$hasYield = $result->hasYield();
 			$throwPoints = array_merge($throwPoints, $result->getThrowPoints());
@@ -2298,7 +2300,16 @@ static function (): void {
 			if ($parametersAcceptor !== null) {
 				$expr = ArgumentsNormalizer::reorderMethodArguments($parametersAcceptor, $expr) ?? $expr;
 			}
-			$result = $this->processArgs($stmt, $methodReflection, $parametersAcceptor, $expr->getArgs(), $scope, $nodeCallback, $context);
+			$result = $this->processArgs(
+				$stmt,
+				$methodReflection,
+				$methodReflection !== null ? $scope->getNakedMethod($calledOnType, $methodReflection->getName()) : null,
+				$parametersAcceptor,
+				$expr->getArgs(),
+				$scope,
+				$nodeCallback,
+				$context,
+			);
 			$scope = $result->getScope();
 
 			if ($methodReflection !== null) {
@@ -2457,7 +2468,7 @@ static function (): void {
 			if ($parametersAcceptor !== null) {
 				$expr = ArgumentsNormalizer::reorderStaticCallArguments($parametersAcceptor, $expr) ?? $expr;
 			}
-			$result = $this->processArgs($stmt, $methodReflection, $parametersAcceptor, $expr->getArgs(), $scope, $nodeCallback, $context, $closureBindScope ?? null);
+			$result = $this->processArgs($stmt, $methodReflection, null, $parametersAcceptor, $expr->getArgs(), $scope, $nodeCallback, $context, $closureBindScope ?? null);
 			$scope = $result->getScope();
 			$scopeFunction = $scope->getFunction();
 
@@ -2792,7 +2803,7 @@ static function (): void {
 			if ($parametersAcceptor !== null) {
 				$expr = ArgumentsNormalizer::reorderNewArguments($parametersAcceptor, $expr) ?? $expr;
 			}
-			$result = $this->processArgs($stmt, $constructorReflection, $parametersAcceptor, $expr->getArgs(), $scope, $nodeCallback, $context);
+			$result = $this->processArgs($stmt, $constructorReflection, null, $parametersAcceptor, $expr->getArgs(), $scope, $nodeCallback, $context);
 			$scope = $result->getScope();
 			$hasYield = $hasYield || $result->hasYield();
 			$throwPoints = array_merge($throwPoints, $result->getThrowPoints());
@@ -3697,6 +3708,7 @@ private function processAttributeGroups(
 	private function processArgs(
 		Node\Stmt $stmt,
 		$calleeReflection,
+		?ExtendedMethodReflection $nakedMethodReflection,
 		?ParametersAcceptor $parametersAcceptor,
 		array $args,
 		MutatingScope $scope,
@@ -3821,7 +3833,25 @@ private function processArgs(
 				}
 			} elseif ($calleeReflection !== null && $calleeReflection->hasSideEffects()->yes()) {
 				$argType = $scope->getType($arg->value);
-				if (!$argType->isObject()->no() || !(new ResourceType())->isSuperTypeOf($argType)->no()) {
+				if (!$argType->isObject()->no()) {
+					$nakedReturnType = null;
+					if ($nakedMethodReflection !== null) {
+						$nakedParametersAcceptor = ParametersAcceptorSelector::selectFromArgs(
+							$scope,
+							$args,
+							$nakedMethodReflection->getVariants(),
+							$nakedMethodReflection->getNamedArgumentsVariants(),
+						);
+						$nakedReturnType = $nakedParametersAcceptor->getReturnType();
+					}
+					if (
+						$nakedReturnType === null
+						|| !(new ThisType($nakedMethodReflection->getDeclaringClass()))->isSuperTypeOf($nakedReturnType)->yes()
+						|| $nakedMethodReflection->isPure()->no()
+					) {
+						$scope = $scope->invalidateExpression($arg->value, true);
+					}
+				} elseif (!(new ResourceType())->isSuperTypeOf($argType)->no()) {
 					$scope = $scope->invalidateExpression($arg->value, true);
 				}
 			}

tests/PHPStan/Analyser/data/impure-method.php

@@ -2,6 +2,7 @@
 
 namespace ImpureMethod;
 
+use stdClass;
 use function PHPStan\Testing\assertType;
 
 /**
@@ -21,7 +22,16 @@ public function voidMethod(): void
 	/**
 	 * @return $this
 	 */
-	public function returnsThis()
+	public function returnsThis($arg)
+	{
+		$this->fooProp = rand(0, 1);
+	}
+
+	/**
+	 * @return $this
+	 * @phpstan-impure
+	 */
+	public function returnsThisImpure($arg)
 	{
 		$this->fooProp = rand(0, 1);
 	}
@@ -67,7 +77,7 @@ public function doFluent(): void
 		$this->fooProp = 1;
 		assertType('1', $this->fooProp);
 
-		$this->returnsThis();
+		$this->returnsThis(new stdClass());
 		assertType('int', $this->fooProp);
 	}
 
@@ -108,3 +118,39 @@ public function doLorem(): void
 	}
 
 }
+
+class Person
+{
+
+	public function getName(): ?string
+	{
+	}
+
+}
+
+class Bar
+{
+
+	public function doFoo(): void
+	{
+		$f = new Foo();
+
+		$p = new Person();
+		assert($p->getName() !== null);
+		assertType('string', $p->getName());
+		$f->returnsThis($p);
+		assertType('string', $p->getName());
+	}
+
+	public function doFoo2(): void
+	{
+		$f = new Foo();
+
+		$p = new Person();
+		assert($p->getName() !== null);
+		assertType('string', $p->getName());
+		$f->returnsThisImpure($p);
+		assertType('string|null', $p->getName());
+	}
+
+}