phpstan · canvural · Nov 10, 2025 · Nov 11, 2025
diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
@@ -1443,6 +1443,18 @@ parameters:
 			count: 1
 			path: src/Type/IterableType.php
 
+		-
+			rawMessage: 'Doing instanceof PHPStan\Type\NeverType is error-prone and deprecated. Use Type::isNever() or Type::isExplicitNever() instead.'
+			identifier: phpstanApi.instanceofType
+			count: 2
+			path: src/Type/NeverType.php
+
+		-
+			rawMessage: 'Doing instanceof PHPStan\Type\NeverType is error-prone and deprecated. Use Type::isNever() or Type::isExplicitNever() instead.'
+			identifier: phpstanApi.instanceofType
+			count: 1
+			path: src/Type/NonAcceptingNeverType.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
@@ -1785,6 +1797,12 @@ parameters:
 			count: 1
 			path: src/Type/TypehintHelper.php
 
+		-
+			rawMessage: 'Call to an undefined method PHPStan\Type\Type::isSubTypeOf().'
+			identifier: method.notFound
+			count: 1
+			path: src/Type/UnionType.php
+
 		-
 			rawMessage: 'Doing instanceof PHPStan\Type\CallableType is error-prone and deprecated. Use Type::isCallable() and Type::getCallableParametersAcceptors() instead.'
 			identifier: phpstanApi.instanceofType

diff --git a/src/Analyser/MutatingScope.php b/src/Analyser/MutatingScope.php
@@ -1068,7 +1068,7 @@ private function resolveType(string $exprString, Expr $node): Type
 			) {
 				return new BooleanType();
 			}
-			if ($expressionType instanceof NeverType) {
+			if (!$expressionType->isNever()->no()) {
 				return new ConstantBooleanType(false);
 			}
 
@@ -4578,8 +4578,8 @@ public function removeTypeFromExpression(Expr $expr, Type $typeToRemove): self
 	{
 		$exprType = $this->getType($expr);
 		if (
-			$exprType instanceof NeverType ||
-			$typeToRemove instanceof NeverType
+			!$exprType->isNever()->no() ||
+			!$typeToRemove->isNever()->no()
 		) {
 			return $this;
 		}
@@ -5891,7 +5891,7 @@ private function exactInstantiation(New_ $node, string $className): ?Type
 		}
 
 		$methodResult = $this->getType($methodCall);
-		if ($methodResult instanceof NeverType && $methodResult->isExplicit()) {
+		if ($methodResult->isExplicitNever()->yes()) {
 			return $methodResult;
 		}
 
@@ -6347,7 +6347,7 @@ public function getIterableKeyType(Type $iteratee): Type
 	{
 		if ($iteratee instanceof UnionType) {
 			$filtered = $iteratee->filterTypes(static fn (Type $innerType) => $innerType->isIterable()->yes());
-			if (!$filtered instanceof NeverType) {
+			if ($filtered->isNever()->no()) {
 				$iteratee = $filtered;
 			}
 		}
@@ -6359,7 +6359,7 @@ public function getIterableValueType(Type $iteratee): Type
 	{
 		if ($iteratee instanceof UnionType) {
 			$filtered = $iteratee->filterTypes(static fn (Type $innerType) => $innerType->isIterable()->yes());
-			if (!$filtered instanceof NeverType) {
+			if ($filtered->isNever()->no()) {
 				$iteratee = $filtered;
 			}
 		}

diff --git a/src/Analyser/NodeScopeResolver.php b/src/Analyser/NodeScopeResolver.php
@@ -1748,7 +1748,7 @@
 				}
 			}
 
-			$exhaustive = $scopeForBranches->getType($stmt->cond) instanceof NeverType;
+			$exhaustive = $scopeForBranches->getType($stmt->cond)->isNever()->yes();
 
 			if (!$hasDefaultCase && !$exhaustive) {
 				$alwaysTerminating = false;
@@ -1893,7 +1893,7 @@
 				foreach ($throwPoints as $throwPoint) {
 					$newThrowPoint = $throwPoint->subtractCatchType($originalCatchType);
 
-					if ($newThrowPoint->getType() instanceof NeverType) {
+					if (!$newThrowPoint->getType()->isNever()->no()) {
 						continue;
 					}
 
@@ -2489,7 +2489,7 @@
 		}
 
 		$exprType = $scope->getType($expr);
-		if ($exprType instanceof NeverType && $exprType->isExplicit()) {
+		if ($exprType->isExplicitNever()->yes()) {
 			return $expr;
 		}
 
@@ -2709,7 +2709,7 @@
 			if ($parametersAcceptor !== null) {
 				$expr = ArgumentsNormalizer::reorderFuncArguments($parametersAcceptor, $expr) ?? $expr;
 				$returnType = $parametersAcceptor->getReturnType();
-				$isAlwaysTerminating = $isAlwaysTerminating || $returnType instanceof NeverType && $returnType->isExplicit();
+				$isAlwaysTerminating = $isAlwaysTerminating || $returnType->isExplicitNever()->yes();
 			}
 
 			if (
@@ -3032,7 +3032,7 @@
 			if ($parametersAcceptor !== null) {
 				$expr = ArgumentsNormalizer::reorderMethodArguments($parametersAcceptor, $expr) ?? $expr;
 				$returnType = $parametersAcceptor->getReturnType();
-				$isAlwaysTerminating = $returnType instanceof NeverType && $returnType->isExplicit();
+				$isAlwaysTerminating = $returnType->isExplicitNever()->yes();
 			}
 
 			$result = $this->processArgs(
@@ -3224,7 +3224,7 @@
 			if ($parametersAcceptor !== null) {
 				$expr = ArgumentsNormalizer::reorderStaticCallArguments($parametersAcceptor, $expr) ?? $expr;
 				$returnType = $parametersAcceptor->getReturnType();
-				$isAlwaysTerminating = $returnType instanceof NeverType && $returnType->isExplicit();
+				$isAlwaysTerminating = $returnType->isExplicitNever()->yes();
 			}
 			$result = $this->processArgs($stmt, $methodReflection, null, $parametersAcceptor, $expr, $scope, $nodeCallback, $context, $closureBindScope ?? null);
 			$scope = $result->getScope();
@@ -3450,7 +3450,7 @@
 			$leftResult = $this->processExprNode($stmt, $expr->left, $scope, $nodeCallback, $context->enterDeep());
 			$rightResult = $this->processExprNode($stmt, $expr->right, $leftResult->getTruthyScope(), $nodeCallback, $context);
 			$rightExprType = $rightResult->getScope()->getType($expr->right);
-			if ($rightExprType instanceof NeverType && $rightExprType->isExplicit()) {
+			if ($rightExprType->isExplicitNever()->yes()) {
 				$leftMergedWithRightScope = $leftResult->getFalseyScope();
 			} else {
 				$leftMergedWithRightScope = $leftResult->getScope()->mergeWith($rightResult->getScope());
@@ -3471,7 +3471,7 @@
 			$leftResult = $this->processExprNode($stmt, $expr->left, $scope, $nodeCallback, $context->enterDeep());
 			$rightResult = $this->processExprNode($stmt, $expr->right, $leftResult->getFalseyScope(), $nodeCallback, $context);
 			$rightExprType = $rightResult->getScope()->getType($expr->right);
-			if ($rightExprType instanceof NeverType && $rightExprType->isExplicit()) {
+			if ($rightExprType->isExplicitNever()->yes()) {
 				$leftMergedWithRightScope = $leftResult->getTruthyScope();
 			} else {
 				$leftMergedWithRightScope = $leftResult->getScope()->mergeWith($rightResult->getScope());
@@ -3498,7 +3498,7 @@
 			$rightScope = $scope->filterByFalseyValue($expr);
 			$rightResult = $this->processExprNode($stmt, $expr->right, $rightScope, $nodeCallback, $context->enterDeep());
 			$rightExprType = $scope->getType($expr->right);
-			if ($rightExprType instanceof NeverType && $rightExprType->isExplicit()) {
+			if ($rightExprType->isExplicitNever()->yes()) {
 				$scope = $scope->filterByTruthyValue(new Expr\Isset_([$expr->left]));
 			} else {
 				$scope = $scope->filterByTruthyValue(new Expr\Isset_([$expr->left]))->mergeWith($rightResult->getScope());
@@ -3936,12 +3936,12 @@
 			} elseif ($condType->isFalse()->yes()) {
 				$finalScope = $ifFalseScope;
 			} else {
-				if ($ifTrueType instanceof NeverType && $ifTrueType->isExplicit()) {
+				if ($ifTrueType !== null && $ifTrueType->isExplicitNever()->yes()) {
 					$finalScope = $ifFalseScope;
 				} else {
 					$ifFalseType = $ifFalseScope->getType($expr->else);
 
-					if ($ifFalseType instanceof NeverType && $ifFalseType->isExplicit()) {
+					if ($ifFalseType->isExplicitNever()->yes()) {
 						$finalScope = $ifTrueScope;
 					} else {
 						$finalScope = $ifTrueScope->mergeWith($ifFalseScope);
@@ -4196,7 +4196,7 @@
 			}
 
 			$remainingType = $matchScope->getType($expr->cond);
-			if (!$hasDefaultCond && !$hasAlwaysTrueCond && !$remainingType instanceof NeverType) {
+			if (!$hasDefaultCond && !$hasAlwaysTrueCond && $remainingType->isNever()->no()) {
 				$throwPoints[] = ThrowPoint::createExplicit($scope, new ObjectType(UnhandledMatchError::class), $expr, false);
 			}
 
@@ -4502,7 +4502,7 @@
 		$throwType = $functionReflection->getThrowType();
 		if ($throwType === null && $parametersAcceptor !== null) {
 			$returnType = $parametersAcceptor->getReturnType();
-			if ($returnType instanceof NeverType && $returnType->isExplicit()) {
+			if ($returnType->isExplicitNever()->yes()) {
 				$throwType = new ObjectType(Throwable::class);
 			}
 		}
@@ -4560,7 +4560,7 @@
 		$throwType = $methodReflection->getThrowType();
 		if ($throwType === null) {
 			$returnType = $parametersAcceptor->getReturnType();
-			if ($returnType instanceof NeverType && $returnType->isExplicit()) {
+			if ($returnType->isExplicitNever()->yes()) {
 				$throwType = new ObjectType(Throwable::class);
 			}
 		}
@@ -4857,7 +4857,7 @@
 		}
 
 		$returnType = $closureType->getReturnType();
-		$isAlwaysTerminating = ($returnType instanceof NeverType && $returnType->isExplicit());
+		$isAlwaysTerminating = ($returnType->isExplicitNever()->yes());
 
 		$nodeCallback(new InClosureNode($closureType, $expr), $closureScope);
 
@@ -5545,7 +5545,7 @@
 							$throwPoints = array_merge($throwPoints, $callableThrowPoints);
 							$impurePoints = array_merge($impurePoints, array_map(static fn (SimpleImpurePoint $impurePoint) => new ImpurePoint($scope, $arg->value, $impurePoint->getIdentifier(), $impurePoint->getDescription(), $impurePoint->isCertain()), $acceptors[0]->getImpurePoints()));
 							$returnType = $acceptors[0]->getReturnType();
-							$isAlwaysTerminating = $isAlwaysTerminating || ($returnType instanceof NeverType && $returnType->isExplicit());
+							$isAlwaysTerminating = $isAlwaysTerminating || ($returnType->isExplicitNever()->yes());
 						}
 					}
 				}
@@ -6961,7 +6961,7 @@
 				$endNode = $executionEnd->getNode();
 				if ($endNode instanceof Node\Stmt\Expression) {
 					$exprType = $statementResult->getScope()->getType($endNode->expr);
-					if ($exprType instanceof NeverType && $exprType->isExplicit()) {
+					if ($exprType->isExplicitNever()->yes()) {
 						continue;
 					}
 				}

diff --git a/src/Node/ClassPropertiesNode.php b/src/Node/ClassPropertiesNode.php
@@ -21,7 +21,6 @@
 use PHPStan\Reflection\MethodReflection;
 use PHPStan\Rules\Properties\ReadWritePropertiesExtensionProvider;
 use PHPStan\TrinaryLogic;
-use PHPStan\Type\NeverType;
 use PHPStan\Type\TypeUtils;
 use function array_diff_key;
 use function array_key_exists;
@@ -276,7 +275,7 @@ private function collectUninitializedProperties(array $constructors, array $unin
 				if ($statementResult->isAlwaysTerminating()) {
 					if ($endNode instanceof Node\Stmt\Expression) {
 						$exprType = $statementResult->getScope()->getType($endNode->expr);
-						if ($exprType instanceof NeverType && $exprType->isExplicit()) {
+						if ($exprType->isExplicitNever()->yes()) {
 							continue;
 						}
 					}

diff --git a/src/Reflection/Callables/FunctionCallableVariant.php b/src/Reflection/Callables/FunctionCallableVariant.php
@@ -9,7 +9,6 @@
 use PHPStan\TrinaryLogic;
 use PHPStan\Type\Generic\TemplateTypeMap;
 use PHPStan\Type\Generic\TemplateTypeVarianceMap;
-use PHPStan\Type\NeverType;
 use PHPStan\Type\ObjectType;
 use PHPStan\Type\Type;
 use Throwable;
@@ -97,7 +96,7 @@ public function getThrowPoints(): array
 		$returnType = $this->variant->getReturnType();
 		$throwType = $this->function->getThrowType();
 		if ($throwType === null) {
-			if ($returnType instanceof NeverType && $returnType->isExplicit()) {
+			if ($returnType->isExplicitNever()->yes()) {
 				$throwType = new ObjectType(Throwable::class);
 			}
 		}

diff --git a/src/Reflection/InitializerExprTypeResolver.php b/src/Reflection/InitializerExprTypeResolver.php
@@ -903,7 +903,7 @@ public function createFirstClassCallable(
 				$returnTypeForThrow = $variant->getReturnType();
 				$throwType = $function->getThrowType();
 				if ($throwType === null) {
-					if ($returnTypeForThrow instanceof NeverType && $returnTypeForThrow->isExplicit()) {
+					if ($returnTypeForThrow->isExplicitNever()->yes()) {
 						$throwType = new ObjectType(Throwable::class);
 					}
 				}
@@ -954,7 +954,7 @@ public function getBitwiseAndType(Expr $left, Expr $right, callable $getTypeCall
 		$leftType = $getTypeCallback($left);
 		$rightType = $getTypeCallback($right);
 
-		if ($leftType instanceof NeverType || $rightType instanceof NeverType) {
+		if ($leftType->isNever()->yes() || $rightType->isNever()->yes()) {
 			return $this->getNeverType($leftType, $rightType);
 		}
 
@@ -1023,7 +1023,7 @@ public function getBitwiseOrType(Expr $left, Expr $right, callable $getTypeCallb
 		$leftType = $getTypeCallback($left);
 		$rightType = $getTypeCallback($right);
 
-		if ($leftType instanceof NeverType || $rightType instanceof NeverType) {
+		if ($leftType->isNever()->yes() || $rightType->isNever()->yes()) {
 			return $this->getNeverType($leftType, $rightType);
 		}
 
@@ -1082,7 +1082,7 @@ public function getBitwiseXorType(Expr $left, Expr $right, callable $getTypeCall
 		$leftType = $getTypeCallback($left);
 		$rightType = $getTypeCallback($right);
 
-		if ($leftType instanceof NeverType || $rightType instanceof NeverType) {
+		if ($leftType->isNever()->yes() || $rightType->isNever()->yes()) {
 			return $this->getNeverType($leftType, $rightType);
 		}
 
@@ -1141,7 +1141,7 @@ public function getSpaceshipType(Expr $left, Expr $right, callable $getTypeCallb
 		$callbackLeftType = $getTypeCallback($left);
 		$callbackRightType = $getTypeCallback($right);
 
-		if ($callbackLeftType instanceof NeverType || $callbackRightType instanceof NeverType) {
+		if ($callbackLeftType->isNever()->yes() || $callbackRightType->isNever()->yes()) {
 			return $this->getNeverType($callbackLeftType, $callbackRightType);
 		}
 
@@ -1228,7 +1228,7 @@ public function getModType(Expr $left, Expr $right, callable $getTypeCallback):
 		$leftType = $getTypeCallback($left);
 		$rightType = $getTypeCallback($right);
 
-		if ($leftType instanceof NeverType || $rightType instanceof NeverType) {
+		if ($leftType->isNever()->yes() || $rightType->isNever()->yes()) {
 			return $this->getNeverType($leftType, $rightType);
 		}
 
@@ -1337,7 +1337,7 @@ public function getPlusType(Expr $left, Expr $right, callable $getTypeCallback):
 		$leftType = $getTypeCallback($left);
 		$rightType = $getTypeCallback($right);
 
-		if ($leftType instanceof NeverType || $rightType instanceof NeverType) {
+		if ($leftType->isNever()->yes() || $rightType->isNever()->yes()) {
 			return $this->getNeverType($leftType, $rightType);
 		}
 
@@ -1645,7 +1645,7 @@ public function getShiftLeftType(Expr $left, Expr $right, callable $getTypeCallb
 		$leftType = $getTypeCallback($left);
 		$rightType = $getTypeCallback($right);
 
-		if ($leftType instanceof NeverType || $rightType instanceof NeverType) {
+		if ($leftType->isNever()->yes() || $rightType->isNever()->yes()) {
 			return $this->getNeverType($leftType, $rightType);
 		}
 
@@ -1704,7 +1704,7 @@ public function getShiftRightType(Expr $left, Expr $right, callable $getTypeCall
 		$leftType = $getTypeCallback($left);
 		$rightType = $getTypeCallback($right);
 
-		if ($leftType instanceof NeverType || $rightType instanceof NeverType) {
+		if ($leftType->isNever()->yes() || $rightType->isNever()->yes()) {
 			return $this->getNeverType($leftType, $rightType);
 		}
 
@@ -1787,7 +1787,7 @@ private function optimizeScalarType(Type $type): Type
 	 */
 	public function resolveIdenticalType(Type $leftType, Type $rightType): TypeResult
 	{
-		if ($leftType instanceof NeverType || $rightType instanceof NeverType) {
+		if ($leftType->isNever()->yes() || $rightType->isNever()->yes()) {
 			return new TypeResult(new ConstantBooleanType(false), []);
 		}
 
@@ -1969,7 +1969,7 @@ private function resolveCommonMath(Expr\BinaryOp $expr, Type $leftType, Type $ri
 		if ($leftNumberType instanceof ErrorType || $rightNumberType instanceof ErrorType) {
 			return new ErrorType();
 		}
-		if ($leftNumberType instanceof NeverType || $rightNumberType instanceof NeverType) {
+		if ($leftNumberType->isNever()->yes() || $rightNumberType->isNever()->yes()) {
 			return $this->getNeverType($leftNumberType, $rightNumberType);
 		}
 
@@ -2587,10 +2587,10 @@ private function getReflectionProvider(): ReflectionProvider
 	private function getNeverType(Type $leftType, Type $rightType): Type
 	{
 		// make sure we don't lose the explicit flag in the process
-		if ($leftType instanceof NeverType && $leftType->isExplicit()) {
+		if ($leftType->isExplicitNever()->yes()) {
 			return $leftType;
 		}
-		if ($rightType instanceof NeverType && $rightType->isExplicit()) {
+		if ($rightType->isExplicitNever()->yes()) {
 			return $rightType;
 		}
 		return new NeverType();

diff --git a/src/Reflection/Php/PhpClassReflectionExtension.php b/src/Reflection/Php/PhpClassReflectionExtension.php
@@ -49,7 +49,6 @@
 use PHPStan\Type\Generic\TemplateTypeMap;
 use PHPStan\Type\Generic\TemplateTypeVariance;
 use PHPStan\Type\MixedType;
-use PHPStan\Type\NeverType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
 use PHPStan\Type\TypehintHelper;
@@ -1161,7 +1160,7 @@ private function inferAndCachePropertyTypes(
 			}
 
 			$propertyType = $methodScope->getType($expr->expr);
-			if ($propertyType instanceof ErrorType || $propertyType instanceof NeverType) {
+			if ($propertyType instanceof ErrorType || !$propertyType->isNever()->no()) {
 				continue;
 			}