Try Rector Online | Rector - Automated Way to Instantly Upgrade and Refactor any PHP code

Run Rector on your code to see what it can do for you:

 <?php
 
 final class DemoFile
 {
-    /**
-     * @return Iterator<DemoFile>
-     */
-    public function run(): Iterator
+    /**
+     * @return \ArrayIterator<DemoFile>
+     */
+    public function run(): \ArrayIterator
     {
         $arr = [new DemoFile];
         return new ArrayIterator($arr);
     }
 }

PHP snippet to change

<?php

final class DemoFile
{
    /**
     * @return Iterator<DemoFile>
     */
    public function run(): Iterator
    {
        $arr = [new DemoFile];
        return new ArrayIterator($arr);
    }
}

Applied Rules:

NarrowObjectReturnTypeRector

Not a change you expect?

Create an issue on GitHub
...or to speed up fix – add a test fixture

Config rector.php

<?php

use Rector\Config\RectorConfig;
use Rector\TypeDeclaration\Rector\ClassMethod\NarrowObjectReturnTypeRector;
use Rector\ValueObject\PhpVersion;

return RectorConfig::configure()
    ->withRules([
        NarrowObjectReturnTypeRector::class
    ])
    // demonstrate specific PHP version
    ->withPhpVersion(PhpVersion::PHP_84);

Rector version: 51d617 - released at 2026-07-12 20:08