add Type::isError method

phpstan-baseline.neon

@@ -1077,6 +1077,12 @@ parameters:
 			count: 2
 			path: src/Type/Enum/EnumCaseObjectType.php
 
+		-
+			rawMessage: 'Doing instanceof PHPStan\Type\ErrorType is error-prone and deprecated. Use Type::isError() instead.'
+			identifier: phpstanApi.instanceofType
+			count: 1
+			path: src/Type/ErrorType.php
+
 		-
 			rawMessage: 'Doing instanceof PHPStan\Type\ConstantScalarType is error-prone and deprecated. Use Type::isConstantScalarValue() or Type::getConstantScalarTypes() or Type::getConstantScalarValues() instead.'
 			identifier: phpstanApi.instanceofType
@@ -1479,6 +1485,12 @@ parameters:
 			count: 1
 			path: src/Type/ObjectType.php
 
+		-
+			rawMessage: 'Doing instanceof PHPStan\Type\ErrorType is error-prone and deprecated. Use Type::isError() instead.'
+			identifier: phpstanApi.instanceofType
+			count: 4
+			path: src/Type/ObjectType.php
+
 		-
 			rawMessage: Doing instanceof PHPStan\Type\Generic\GenericObjectType is error-prone and deprecated.
 			identifier: phpstanApi.instanceofType

src/Analyser/MutatingScope.php

@@ -1802,15 +1802,15 @@ static function (Node $node, Scope $scope) use ($arrowScope, &$arrowFunctionImpu
 
 			$returnType = $functionReflection->getReturnType();
 			$generatorSendType = $returnType->getTemplateType(Generator::class, 'TSend');
-			if ($generatorSendType instanceof ErrorType) {
+			if ($generatorSendType->isError()->yes()) {
 				return new MixedType();
 			}
 
 			return $generatorSendType;
 		} elseif ($node instanceof Expr\YieldFrom) {
 			$yieldFromType = $this->getType($node->expr);
 			$generatorReturnType = $yieldFromType->getTemplateType(Generator::class, 'TReturn');
-			if ($generatorReturnType instanceof ErrorType) {
+			if ($generatorReturnType->isError()->yes()) {
 				return new MixedType();
 			}
 
@@ -6098,7 +6098,7 @@ classReflection: $classReflection->withTypes($types)->asFinal(),
 		return TypeTraverser::map($newGenericType, static function (Type $type, callable $traverse) use ($resolvedTemplateTypeMap): Type {
 			if ($type instanceof TemplateType && !$type->isArgument()) {
 				$newType = $resolvedTemplateTypeMap->getType($type->getName());
-				if ($newType === null || $newType instanceof ErrorType) {
+				if ($newType === null || $newType->isError()->yes()) {
 					return $type->getDefault() ?? $type->getBound();
 				}
 

src/Reflection/ClassReflection.php

@@ -1643,7 +1643,7 @@ public function getActiveTemplateTypeMap(): TemplateTypeMap
 		if ($resolved !== null) {
 			$templateTypeMap = $this->getTemplateTypeMap();
 			return $this->activeTemplateTypeMap = $resolved->map(static function (string $name, Type $type) use ($templateTypeMap): Type {
-				if ($type instanceof ErrorType) {
+				if ($type->isError()->yes()) {
 					$templateType = $templateTypeMap->getType($name);
 					if ($templateType !== null) {
 						return TemplateTypeHelper::resolveToDefaults($templateType);

src/Reflection/InitializerExprTypeResolver.php

@@ -518,7 +518,7 @@ public function resolveConcatType(Type $left, Type $right): Type
 		if (TypeCombinator::union(
 			$leftStringType,
 			$rightStringType,
-		) instanceof ErrorType) {
+		)->isError()->yes()) {
 			return new ErrorType();
 		}
 
@@ -974,7 +974,7 @@ public function getBitwiseAndType(Expr $left, Expr $right, callable $getTypeCall
 							$leftNumberType = $leftTypeInner->toNumber();
 							$rightNumberType = $rightTypeInner->toNumber();
 
-							if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+							if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 								return new ErrorType();
 							}
 
@@ -1001,7 +1001,7 @@ public function getBitwiseAndType(Expr $left, Expr $right, callable $getTypeCall
 		$leftNumberType = $leftType->toNumber();
 		$rightNumberType = $rightType->toNumber();
 
-		if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+		if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 			return new ErrorType();
 		}
 
@@ -1043,7 +1043,7 @@ public function getBitwiseOrType(Expr $left, Expr $right, callable $getTypeCallb
 							$leftNumberType = $leftTypeInner->toNumber();
 							$rightNumberType = $rightTypeInner->toNumber();
 
-							if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+							if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 								return new ErrorType();
 							}
 
@@ -1067,7 +1067,7 @@ public function getBitwiseOrType(Expr $left, Expr $right, callable $getTypeCallb
 			return new StringType();
 		}
 
-		if (TypeCombinator::union($leftType->toNumber(), $rightType->toNumber()) instanceof ErrorType) {
+		if (TypeCombinator::union($leftType->toNumber(), $rightType->toNumber())->isError()->yes()) {
 			return new ErrorType();
 		}
 
@@ -1102,7 +1102,7 @@ public function getBitwiseXorType(Expr $left, Expr $right, callable $getTypeCall
 							$leftNumberType = $leftTypeInner->toNumber();
 							$rightNumberType = $rightTypeInner->toNumber();
 
-							if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+							if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 								return new ErrorType();
 							}
 
@@ -1126,7 +1126,7 @@ public function getBitwiseXorType(Expr $left, Expr $right, callable $getTypeCall
 			return new StringType();
 		}
 
-		if (TypeCombinator::union($leftType->toNumber(), $rightType->toNumber()) instanceof ErrorType) {
+		if (TypeCombinator::union($leftType->toNumber(), $rightType->toNumber())->isError()->yes()) {
 			return new ErrorType();
 		}
 
@@ -1187,7 +1187,7 @@ public function getDivType(Expr $left, Expr $right, callable $getTypeCallback):
 						$leftNumberType = $leftTypeInner->toNumber();
 						$rightNumberType = $rightTypeInner->toNumber();
 
-						if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+						if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 							return new ErrorType();
 						}
 
@@ -1238,7 +1238,7 @@ public function getModType(Expr $left, Expr $right, callable $getTypeCallback):
 			return $extensionSpecified;
 		}
 
-		if ($leftType->toNumber() instanceof ErrorType || $rightType->toNumber() instanceof ErrorType) {
+		if ($leftType->toNumber()->isError()->yes() || $rightType->toNumber()->isError()->yes()) {
 			return new ErrorType();
 		}
 
@@ -1255,7 +1255,7 @@ public function getModType(Expr $left, Expr $right, callable $getTypeCallback):
 						$leftNumberType = $leftTypeInner->toNumber();
 						$rightNumberType = $rightTypeInner->toNumber();
 
-						if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+						if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 							return new ErrorType();
 						}
 
@@ -1354,7 +1354,7 @@ public function getPlusType(Expr $left, Expr $right, callable $getTypeCallback):
 						$leftNumberType = $leftTypeInner->toNumber();
 						$rightNumberType = $rightTypeInner->toNumber();
 
-						if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+						if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 							return new ErrorType();
 						}
 
@@ -1533,7 +1533,7 @@ public function getMinusType(Expr $left, Expr $right, callable $getTypeCallback)
 						$leftNumberType = $leftTypeInner->toNumber();
 						$rightNumberType = $rightTypeInner->toNumber();
 
-						if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+						if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 							return new ErrorType();
 						}
 
@@ -1577,7 +1577,7 @@ public function getMulType(Expr $left, Expr $right, callable $getTypeCallback):
 						$leftNumberType = $leftTypeInner->toNumber();
 						$rightNumberType = $rightTypeInner->toNumber();
 
-						if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+						if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 							return new ErrorType();
 						}
 
@@ -1630,7 +1630,7 @@ public function getPowType(Expr $left, Expr $right, callable $getTypeCallback):
 		}
 
 		$exponentiatedTyped = $leftType->exponentiate($rightType);
-		if (!$exponentiatedTyped instanceof ErrorType) {
+		if (!$exponentiatedTyped->isError()->yes()) {
 			return $exponentiatedTyped;
 		}
 
@@ -1662,7 +1662,7 @@ public function getShiftLeftType(Expr $left, Expr $right, callable $getTypeCallb
 						$leftNumberType = $leftTypeInner->toNumber();
 						$rightNumberType = $rightTypeInner->toNumber();
 
-						if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+						if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 							return new ErrorType();
 						}
 
@@ -1689,7 +1689,7 @@ public function getShiftLeftType(Expr $left, Expr $right, callable $getTypeCallb
 		$leftNumberType = $leftType->toNumber();
 		$rightNumberType = $rightType->toNumber();
 
-		if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+		if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 			return new ErrorType();
 		}
 
@@ -1721,7 +1721,7 @@ public function getShiftRightType(Expr $left, Expr $right, callable $getTypeCall
 						$leftNumberType = $leftTypeInner->toNumber();
 						$rightNumberType = $rightTypeInner->toNumber();
 
-						if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+						if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 							return new ErrorType();
 						}
 
@@ -1748,7 +1748,7 @@ public function getShiftRightType(Expr $left, Expr $right, callable $getTypeCall
 		$leftNumberType = $leftType->toNumber();
 		$rightNumberType = $rightType->toNumber();
 
-		if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+		if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 			return new ErrorType();
 		}
 
@@ -1966,7 +1966,7 @@ private function resolveCommonMath(Expr\BinaryOp $expr, Type $leftType, Type $ri
 			return new ErrorType();
 		}
 
-		if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
+		if ($leftNumberType->isError()->yes() || $rightNumberType->isError()->yes()) {
 			return new ErrorType();
 		}
 		if ($leftNumberType instanceof NeverType || $rightNumberType instanceof NeverType) {

src/Reflection/Php/PhpClassReflectionExtension.php

@@ -41,7 +41,6 @@
 use PHPStan\Type\Constant\ConstantArrayTypeBuilder;
 use PHPStan\Type\Constant\ConstantStringType;
 use PHPStan\Type\Enum\EnumCaseObjectType;
-use PHPStan\Type\ErrorType;
 use PHPStan\Type\FileTypeMapper;
 use PHPStan\Type\GeneralizePrecision;
 use PHPStan\Type\Generic\TemplateMixedType;
@@ -1161,7 +1160,7 @@ private function inferAndCachePropertyTypes(
 			}
 
 			$propertyType = $methodScope->getType($expr->expr);
-			if ($propertyType instanceof ErrorType || $propertyType instanceof NeverType) {
+			if ($propertyType->isError()->yes() || $propertyType instanceof NeverType) {
 				continue;
 			}
 

src/Reflection/ResolvedFunctionVariantWithOriginal.php

@@ -4,7 +4,6 @@
 
 use PHPStan\Reflection\Php\ExtendedDummyParameter;
 use PHPStan\Type\ConditionalTypeForParameter;
-use PHPStan\Type\ErrorType;
 use PHPStan\Type\Generic\GenericObjectType;
 use PHPStan\Type\Generic\GenericStaticType;
 use PHPStan\Type\Generic\TemplateType;
@@ -211,7 +210,7 @@ private function resolveResolvableTemplateTypes(Type $type, TemplateTypeVariance
 				&& $type->getScope()->getFunctionName() !== null
 			) {
 				$newType = $this->resolvedTemplateTypeMap->getType($type->getName());
-				if ($newType === null || $newType instanceof ErrorType) {
+				if ($newType === null || $newType->isError()->yes()) {
 					return $traverse($type);
 				}
 
@@ -252,7 +251,7 @@ private function resolveResolvableTemplateTypes(Type $type, TemplateTypeVariance
 
 			if ($type instanceof TemplateType && !$type->isArgument()) {
 				$newType = $this->resolvedTemplateTypeMap->getType($type->getName());
-				if ($newType === null || $newType instanceof ErrorType) {
+				if ($newType === null || $newType->isError()->yes()) {
 					return $traverse($type);
 				}
 

src/Rules/Api/ApiInstanceofTypeRule.php

@@ -32,6 +32,7 @@
 use PHPStan\Type\Constant\ConstantStringType;
 use PHPStan\Type\ConstantScalarType;
 use PHPStan\Type\Enum\EnumCaseObjectType;
+use PHPStan\Type\ErrorType;
 use PHPStan\Type\FloatType;
 use PHPStan\Type\Generic\GenericClassStringType;
 use PHPStan\Type\Generic\GenericObjectType;
@@ -79,6 +80,7 @@ final class ApiInstanceofTypeRule implements Rule
 		IntersectionType::class => null,
 		ConstantScalarType::class => 'Type::isConstantScalarValue() or Type::getConstantScalarTypes() or Type::getConstantScalarValues()',
 		ObjectShapeType::class => 'Type::isObject() and Type::hasProperty()',
+		ErrorType::class => 'Type::isError()',
 
 		// accessory types
 		NonEmptyArrayType::class => 'Type::isIterableAtLeastOnce()',

src/Rules/Arrays/ArrayDestructuringRule.php

@@ -14,7 +14,6 @@
 use PHPStan\Rules\RuleErrorBuilder;
 use PHPStan\Rules\RuleLevelHelper;
 use PHPStan\Type\Constant\ConstantIntegerType;
-use PHPStan\Type\ErrorType;
 use PHPStan\Type\ObjectType;
 use PHPStan\Type\Type;
 use PHPStan\Type\VerbosityLevel;
@@ -65,7 +64,7 @@ private function getErrors(Scope $scope, Node\Expr\List_ $var, Expr $expr): arra
 			static fn (Type $varType): bool => $varType->isArray()->yes() || (new ObjectType(ArrayAccess::class))->isSuperTypeOf($varType)->yes(),
 		);
 		$exprType = $exprTypeResult->getType();
-		if ($exprType instanceof ErrorType) {
+		if ($exprType->isError()->yes()) {
 			return [];
 		}
 		if (!$exprType->isArray()->yes() && !(new ObjectType(ArrayAccess::class))->isSuperTypeOf($exprType)->yes()) {

src/Rules/Arrays/ArrayUnpackingRule.php

@@ -11,7 +11,6 @@
 use PHPStan\Rules\Rule;
 use PHPStan\Rules\RuleErrorBuilder;
 use PHPStan\Rules\RuleLevelHelper;
-use PHPStan\Type\ErrorType;
 use PHPStan\Type\Type;
 use PHPStan\Type\VerbosityLevel;
 use function sprintf;
@@ -46,7 +45,7 @@ public function processNode(Node $node, Scope $scope): array
 		);
 
 		$keyType = $typeResult->getType();
-		if ($keyType instanceof ErrorType) {
+		if ($keyType->isError()->yes()) {
 			return $typeResult->getUnknownClassErrors();
 		}
 

src/Rules/Arrays/InvalidKeyInArrayDimFetchRule.php

@@ -10,7 +10,6 @@
 use PHPStan\Rules\Rule;
 use PHPStan\Rules\RuleErrorBuilder;
 use PHPStan\Rules\RuleLevelHelper;
-use PHPStan\Type\ErrorType;
 use PHPStan\Type\Type;
 use PHPStan\Type\VerbosityLevel;
 use function sprintf;
@@ -49,7 +48,7 @@ public function processNode(Node $node, Scope $scope): array
 			static fn (Type $varType): bool => $varType->isArray()->no(),
 		)->getType();
 
-		if ($varType instanceof ErrorType) {
+		if ($varType->isError()->yes()) {
 			return [];
 		}
 
@@ -65,7 +64,7 @@ public function processNode(Node $node, Scope $scope): array
 			'',
 			static fn (Type $dimType): bool => $allowedArrayKeys->isSuperTypeOf($dimType)->yes(),
 		)->getType();
-		if ($dimensionType instanceof ErrorType) {
+		if ($dimensionType->isError()->yes()) {
 			return [];
 		}
 

src/Rules/Arrays/InvalidKeyInArrayItemRule.php

@@ -9,7 +9,6 @@
 use PHPStan\Rules\Rule;
 use PHPStan\Rules\RuleErrorBuilder;
 use PHPStan\Rules\RuleLevelHelper;
-use PHPStan\Type\ErrorType;
 use PHPStan\Type\Type;
 use PHPStan\Type\VerbosityLevel;
 use function sprintf;
@@ -46,7 +45,7 @@ public function processNode(Node $node, Scope $scope): array
 			'',
 			static fn (Type $dimType): bool => $allowedArrayKeys->isSuperTypeOf($dimType)->yes(),
 		)->getType();
-		if ($dimensionType instanceof ErrorType) {
+		if ($dimensionType->isError()->yes()) {
 			return [];
 		}
 

src/Rules/Arrays/IterableInForeachRule.php

@@ -9,7 +9,6 @@
 use PHPStan\Rules\Rule;
 use PHPStan\Rules\RuleErrorBuilder;
 use PHPStan\Rules\RuleLevelHelper;
-use PHPStan\Type\ErrorType;
 use PHPStan\Type\Type;
 use PHPStan\Type\VerbosityLevel;
 use function sprintf;
@@ -40,7 +39,7 @@ public function processNode(Node $node, Scope $scope): array
 			static fn (Type $type): bool => $type->isIterable()->yes(),
 		);
 		$type = $typeResult->getType();
-		if ($type instanceof ErrorType) {
+		if ($type->isError()->yes()) {
 			return $typeResult->getUnknownClassErrors();
 		}
 		if ($type->isIterable()->yes()) {