NarrowParamUnionToCollectionRector

Narrow union param docblock type to Collection type in class method

 use Doctrine\Common\Collections\Collection;

 class SomeClass
 {
     /**
-     * @param Collection|array $items
+     * @param Collection $items
      */
     public function run($items)
     {
     }
 }

Configure your rector.php:

<?php

use Rector\Config\RectorConfig;
use Rector\Doctrine\TypedCollections\Rector\ClassMethod\NarrowParamUnionToCollectionRector;

return RectorConfig::configure()
    ->withRules([
        NarrowParamUnionToCollectionRector::class,
    ]);