feat: Handle case when preg_split returns false

Author: malsuke

Diff for: src/Type/Php/PregSplitDynamicReturnTypeExtension.php

@@ -26,6 +26,7 @@
 use PHPStan\Type\StringType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
+use PHPUnit\Framework\Assert;
 use function count;
 use function is_array;
 use function is_int;
@@ -157,6 +158,9 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 				foreach ($limits as $limit) {
 					foreach ($flags as $flag) {
 						$result = @preg_split($patternConstantType->getValue(), $subjectConstantType->getValue(), (int) $limit, (int) $flag);
+						if ($result === false) {
+							return new ErrorType();
+						}
 						$constantArray = ConstantArrayTypeBuilder::createEmpty();
 						foreach ($result as $key => $value) {
 							if (is_array($value)) {