[Php81] Skip param reassign on ReadOnlyPropertyRector (#2498)

* [Php81] Skip param reassign on ReadOnlyPropertyRector

* Fixed 🎉

* clean up

* final touch: eol

* [ci-review] Rector Rectify

Co-authored-by: GitHub Action <action@github.com>

rules-tests/Php81/Rector/Property/ReadOnlyPropertyRector/Fixture/skip_param_reassign.php.inc

@@ -0,0 +1,13 @@
+<?php
+
+namespace Rector\Tests\Php81\Rector\Property\ReadOnlyPropertyRector\Fixture;
+
+final class SkipParamReassign
+{
+    public function __construct(private string $foo)
+    {
+        $foo = 'bar';
+
+        $this->foo = $foo;
+    }
+}

rules/Php81/Rector/Property/ReadOnlyPropertyRector.php

@@ -8,6 +8,7 @@
 use PhpParser\Node\Expr;
 use PhpParser\Node\Param;
 use PhpParser\Node\Stmt\Property;
+use Rector\Core\NodeAnalyzer\ParamAnalyzer;
 use Rector\Core\NodeManipulator\PropertyFetchAssignManipulator;
 use Rector\Core\NodeManipulator\PropertyManipulator;
 use Rector\Core\Rector\AbstractRector;
@@ -29,6 +30,7 @@ final class ReadOnlyPropertyRector extends AbstractRector implements MinPhpVersi
     public function __construct(
         private readonly PropertyManipulator $propertyManipulator,
         private readonly PropertyFetchAssignManipulator $propertyFetchAssignManipulator,
+        private readonly ParamAnalyzer $paramAnalyzer,
         private readonly VisibilityManipulator $visibilityManipulator,
     ) {
     }
@@ -156,6 +158,10 @@ private function refactorParam(Param $param): Param | null
             return null;
         }
 
+        if ($this->paramAnalyzer->isParamReassign($param)) {
+            return null;
+        }
+
         $this->visibilityManipulator->makeReadonly($param);
         return $param;
     }

src/NodeAnalyzer/ParamAnalyzer.php

@@ -5,6 +5,7 @@
 namespace Rector\Core\NodeAnalyzer;
 
 use PhpParser\Node;
+use PhpParser\Node\Expr\Assign;
 use PhpParser\Node\Expr\CallLike;
 use PhpParser\Node\Expr\Closure;
 use PhpParser\Node\Expr\ConstFetch;
@@ -19,8 +20,10 @@
 use PhpParser\NodeTraverser;
 use Rector\Core\NodeManipulator\FuncCallManipulator;
 use Rector\Core\PhpParser\Comparing\NodeComparator;
+use Rector\Core\PhpParser\Node\BetterNodeFinder;
 use Rector\Core\PhpParser\Node\Value\ValueResolver;
 use Rector\NodeNameResolver\NodeNameResolver;
+use Rector\NodeTypeResolver\Node\AttributeKey;
 use Symplify\Astral\NodeTraverser\SimpleCallableNodeTraverser;
 
 final class ParamAnalyzer
@@ -31,6 +34,7 @@ public function __construct(
         private readonly NodeNameResolver $nodeNameResolver,
         private readonly FuncCallManipulator $funcCallManipulator,
         private readonly SimpleCallableNodeTraverser $simpleCallableNodeTraverser,
+        private readonly BetterNodeFinder $betterNodeFinder
     ) {
     }
 
@@ -101,6 +105,30 @@ public function hasDefaultNull(Param $param): bool
         return $param->default instanceof ConstFetch && $this->valueResolver->isNull($param->default);
     }
 
+    public function isParamReassign(Param $param): bool
+    {
+        $classMethod = $param->getAttribute(AttributeKey::PARENT_NODE);
+
+        if (! $classMethod instanceof ClassMethod) {
+            return false;
+        }
+
+        $paramName = (string) $this->nodeNameResolver->getName($param->var);
+        return (bool) $this->betterNodeFinder->findFirstInFunctionLikeScoped($classMethod, function (Node $node) use (
+            $paramName
+        ): bool {
+            if (! $node instanceof Assign) {
+                return false;
+            }
+
+            if (! $node->var instanceof Variable) {
+                return false;
+            }
+
+            return $this->nodeNameResolver->isName($node->var, $paramName);
+        });
+    }
+
     private function isVariableInClosureUses(Closure $closure, Variable $variable): bool
     {
         foreach ($closure->uses as $use) {