[TypeDeclaration] Ensure return $node only when changed on AddParamTy…

…peDeclarationRector (#2399)

rules/TypeDeclaration/Rector/ClassMethod/AddParamTypeDeclarationRector.php

@@ -34,6 +34,8 @@ final class AddParamTypeDeclarationRector extends AbstractRector implements Conf
      */
     private array $addParamTypeDeclarations = [];
 
+    private bool $hasChanged = false;
+
     public function __construct(
         private readonly TypeComparator $typeComparator,
         private readonly PhpVersionProvider $phpVersionProvider,
@@ -99,6 +101,10 @@ public function refactor(Node $node): ?Node
             $this->refactorClassMethodWithTypehintByParameterPosition($node, $addParamTypeDeclaration);
         }
 
+        if (! $this->hasChanged) {
+            return null;
+        }
+
         return $node;
     }
 
@@ -157,7 +163,6 @@ private function refactorClassMethodWithTypehintByParameterPosition(
 
     private function refactorParameter(Param $param, AddParamTypeDeclaration $addParamTypeDeclaration): void
     {
-
         // already set → no change
         if ($param->type !== null) {
             $currentParamType = $this->staticTypeMapper->mapPhpParserNodePHPStanType($param->type);
@@ -171,6 +176,8 @@ private function refactorParameter(Param $param, AddParamTypeDeclaration $addPar
             TypeKind::PARAM
         );
 
+        $this->hasChanged = true;
+
         // remove it
         if ($addParamTypeDeclaration->getParamType() instanceof MixedType) {
             if ($this->phpVersionProvider->isAtLeastPhpVersion(PhpVersionFeature::MIXED_TYPE)) {