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StaticClosureRector

Changes Closure to be static when possible

-function () {
+static function () {
     if (rand(0, 1)) {
         return 1;
     }

     return 2;
 }

Configure your rector.php:

<?php

use Rector\CodingStyle\Rector\Closure\StaticClosureRector;
use Rector\Config\RectorConfig;

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