From e9c69b2097be39468b2be6a2dcf4a9867abaa884 Mon Sep 17 00:00:00 2001
From: Tomas Votruba <tomas.vot@gmail.com>
Date: Sat, 17 Oct 2026 17:21:24 +0200
Subject: [PATCH] skip NullToStrictString arg already cast to target type

Guard against nesting a redundant cast when the converter re-processes a value already cast or literal of the target type (or a ternary whose branches are). Structural check, immune to stale resolved types on re-printed nodes.
---
 .../NullToStrictStringIntConverter.php        | 25 +++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/rules/Php81/NodeManipulator/NullToStrictStringIntConverter.php b/rules/Php81/NodeManipulator/NullToStrictStringIntConverter.php
index 6a2c3454d66..862c5a48868 100644
--- a/rules/Php81/NodeManipulator/NullToStrictStringIntConverter.php
+++ b/rules/Php81/NodeManipulator/NullToStrictStringIntConverter.php
@@ -98,6 +98,11 @@ public function convertIfNull(
             return $funcCall;
         }
 
+        // already cast to the target type on a previous run, re-casting would nest a redundant cast
+        if ($this->isAlreadyCastToTargetType($argValue, $targetType)) {
+            return null;
+        }
+
         $wrapInParentheses = false;
         if ($argValue instanceof Ternary && $argValue->cond instanceof CastString_) {
             $wrapInParentheses = true;
@@ -118,6 +123,26 @@ public function convertIfNull(
         return $funcCall;
     }
 
+    /**
+     * Structural check (immune to stale resolved types on re-printed nodes): the value is already a
+     * cast/literal of the target type, or a ternary whose both branches are.
+     */
+    private function isAlreadyCastToTargetType(Expr $expr, string $targetType): bool
+    {
+        if ($expr instanceof Ternary) {
+            // short ternary "A ?: B" keeps the left value in cond; full ternary uses if
+            $left = $expr->if ?? $expr->cond;
+            return $this->isAlreadyCastToTargetType($left, $targetType)
+                && $this->isAlreadyCastToTargetType($expr->else, $targetType);
+        }
+
+        if ($targetType === 'string') {
+            return $expr instanceof CastString_ || $expr instanceof String_ || $expr instanceof InterpolatedString;
+        }
+
+        return $expr instanceof CastInt_ || $expr instanceof Int_;
+    }
+
     private function shouldSkipValue(Expr $expr, Scope $scope, bool $isTrait, string $targetType): bool
     {
         // array dim fetch value is mixed, null is not known - skip to avoid wrong (string) cast