Get rid of instanceof *Type checks

Author: staabm

phpstan-baseline.neon

@@ -1521,12 +1521,6 @@ parameters:
 			count: 2
 			path: src/Type/Php/ArrayCombineFunctionReturnTypeExtension.php
 
-		-
-			rawMessage: 'Doing instanceof PHPStan\Type\Constant\ConstantStringType is error-prone and deprecated. Use Type::getConstantStrings() instead.'
-			identifier: phpstanApi.instanceofType
-			count: 1
-			path: src/Type/Php/ArrayCombineFunctionReturnTypeExtension.php
-
 		-
 			rawMessage: 'Doing instanceof PHPStan\Type\Constant\ConstantStringType is error-prone and deprecated. Use Type::getConstantStrings() instead.'
 			identifier: phpstanApi.instanceofType

src/Type/Php/ArrayCombineFunctionReturnTypeExtension.php

@@ -15,6 +15,7 @@
 use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\Constant\ConstantIntegerType;
 use PHPStan\Type\Constant\ConstantStringType;
+use PHPStan\Type\ConstantScalarType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
 use PHPStan\Type\ErrorType;
 use PHPStan\Type\MixedType;
@@ -23,6 +24,8 @@
 use PHPStan\Type\TypeCombinator;
 use PHPStan\Type\UnionType;
 use function count;
+use function is_int;
+use function is_string;
 
 #[AutowiredService]
 final class ArrayCombineFunctionReturnTypeExtension implements DynamicFunctionReturnTypeExtension
@@ -114,7 +117,7 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 	/**
 	 * @param array<int, Type> $types
 	 *
-	 * @return array<int, ConstantIntegerType|ConstantStringType>|null
+	 * @return list<ConstantScalarType>|null
 	 */
 	private function sanitizeConstantArrayKeyTypes(array $types): ?array
 	{
@@ -125,14 +128,19 @@ private function sanitizeConstantArrayKeyTypes(array $types): ?array
 				$type = $type->toString();
 			}
 
-			if (
-				!$type instanceof ConstantIntegerType
-				&& !$type instanceof ConstantStringType
-			) {
+			$scalars = $type->getConstantScalarTypes();
+			if (count($scalars) === 0) {
 				return null;
 			}
 
-			$sanitizedTypes[] = $type;
+			foreach ($scalars as $scalar) {
+				$value = $scalar->getValue();
+				if (!is_int($value) && !is_string($value)) {
+					return null;
+				}
+
+				$sanitizedTypes[] = $scalar;
+			}
 		}
 
 		return $sanitizedTypes;