Converts arrow function and closures to first class callable
-function ($parameter) {
-    return Call::to($parameter);
-}
+Call::to(...);
                        Configure your rector.php:
<?php
use Rector\CodingStyle\Rector\FunctionLike\FunctionLikeToFirstClassCallableRector;
use Rector\Config\RectorConfig;
return RectorConfig::configure()
    ->withRules([
        FunctionLikeToFirstClassCallableRector::class,
    ]);