Get rid of last instanceof in extension

Author: herndlm

phpstan-baseline.neon

@@ -1461,12 +1461,6 @@ parameters:
 			count: 1
 			path: src/Type/Php/ArrayKeyExistsFunctionTypeSpecifyingExtension.php
 
-		-
-			message: '#^Doing instanceof PHPStan\\Type\\Constant\\ConstantArrayType is error\-prone and deprecated\. Use Type\:\:getConstantArrays\(\) instead\.$#'
-			identifier: phpstanApi.instanceofType
-			count: 1
-			path: src/Type/Php/ArrayMergeFunctionDynamicReturnTypeExtension.php
-
 		-
 			message: '#^Doing instanceof PHPStan\\Type\\ConstantScalarType is error\-prone and deprecated\. Use Type\:\:isConstantScalarValue\(\) or Type\:\:getConstantScalarTypes\(\) or Type\:\:getConstantScalarValues\(\) instead\.$#'
 			identifier: phpstanApi.instanceofType

src/Type/Php/ArrayMergeFunctionDynamicReturnTypeExtension.php

@@ -45,8 +45,13 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 			$argType = $scope->getType($arg->value);
 
 			if ($arg->unpack) {
-				if ($argType instanceof ConstantArrayType) {
-					$argTypesFound = $argType->getValueTypes();
+				if ($argType->isConstantArray()->yes()) {
+					$argTypesFound = [];
+					foreach ($argType->getConstantArrays() as $constantArray) {
+						foreach ($constantArray->getValueTypes() as $valueType) {
+							$argTypesFound[] = $valueType;
+						}
+					}
 				} else {
 					$argTypesFound = [$argType->getIterableValueType()];
 				}