Increment on non-numeric string is deprecated, use str_increment() instead

Author: staabm

src/Analyser/MutatingScope.php

@@ -150,6 +150,7 @@
 use function array_values;
 use function count;
 use function explode;
+use function function_exists;
 use function get_class;
 use function implode;
 use function in_array;
@@ -160,6 +161,8 @@
 use function ltrim;
 use function md5;
 use function sprintf;
+use function str_decrement;
+use function str_increment;
 use function str_starts_with;
 use function strlen;
 use function strtolower;
@@ -1733,10 +1736,18 @@ static function (Node $node, Scope $scope) use ($arrowScope, &$arrowFunctionImpu
 				foreach ($varScalars as $varValue) {
 					if ($node instanceof Expr\PreInc) {
 						if (!is_bool($varValue)) {
-							++$varValue;
+							if (function_exists('str_increment')) {
+								$varValue = str_increment($varValue);
+							} else {
+								++$varValue;
+							}
 						}
 					} elseif (is_numeric($varValue)) {
-						--$varValue;
+						if (function_exists('str_decrement')) {
+							$varValue = str_decrement($varValue);
+						} else {
+							--$varValue;
+						}
 					}
 
 					$newTypes[] = $this->getTypeFromValue($varValue);