Introduction

Rector requires PHP 7.2+. It can work with PHP 5.x and 8.x code. It works best with OOP, typed code with separated PHP and template layers.

Install

composer require rector/rector --dev

You can run it from your bin directory:

vendor/bin/rector

First Run

Rector works with rector.php config file. You can create it manually, or Rector handle it for you:

vendor/bin/rector

 No "rector.php" config found. Should we generate it for you? [yes]:
 > yes


 [OK] The config is added now. Re-run command to make Rector do the work!

In rector.php you can define paths, rules and sets you want to run on your code:

<?php

use Rector\Config\RectorConfig;
use Rector\Set\ValueObject\SetList;

return RectorConfig::configure()
    ->withPaths([
        __DIR__ . '/src',
        __DIR__ . '/tests',
    ])
    ->withPreparedSets(deadCode: true);

If you're on PHP 7.x, you can use withSets() instead, so for the deadCode set, you can define:
-   ->withPreparedSets(deadCode: true);
+   ->withSets([SetList::DEAD_CODE]);

To see preview of suggested changed, run process command with --dry-run option:

vendor/bin/rector process --dry-run

To make changes happen, run bare command:

vendor/bin/rector process