Introducing Composer Version-Based Sets

At the moment, we have to add sets manually one by one to rector.php:

return RectorConfig::configure()
    ->withSets([
        \Rector\Symfony\Set\TwigSetList::TWIG_112,
        \Rector\Symfony\Set\TwigSetList::TWIG_127,
        \Rector\Symfony\Set\TwigSetList::TWIG_134,
        \Rector\Symfony\Set\TwigSetList::TWIG_20,
        \Rector\Symfony\Set\TwigSetList::TWIG_24,
    ])

This doesn't seem right for a couple of reasons:

• we have to always check if there is a new set we should add here
• if we use Twig 2, there is no point in running Twig 1 set - they also may cause an error as syntax evolves
• if we use Twig 1.20, we don't want 1.40 sets to run as they might break the code

What should happen instead?#

• Rector should look into installed composer.json version of twig/twig
• then check all Twig sets and find those that make sense to apply
• run those

If we upgrade to Twig 3 later on, Rector should pick up sets for Twig 3 for us. So, we don't maintain the rector.php at all.

Introducing withComposerBased()#

return RectorConfig::configure()
    ->withComposerBased(twig: true);

You can drop all sets from above and use this single parameter. Currently, we support Twig, PHPUnit, and Doctrine. Support for Symfony and Laravel is coming soon.

How does it work?#

Rector will go through all Twig sets and check our installed version in vendor/composer/installed.json. Then, it finds all sets relevant to our specific version.

If you're writing your custom extension for your community, you'll want to create your own SetProvider to handle complexity for your users.

Let's look at a real example for TwigSetProvider from the rector-symfony package:

namespace Rector\Symfony\Set\SetProvider;

use Rector\Set\Contract\SetInterface;
use Rector\Set\Contract\SetProviderInterface;
use Rector\Set\ValueObject\ComposerTriggeredSet;
use Rector\Set\ValueObject\Set;

final class TwigSetProvider implements SetProviderInterface
{
    /**
     * @return SetInterface[]
     */
    public function provide(): array
    {
        return [
            new ComposerTriggeredSet(
                'twig',
                'twig/twig',
                '1.27',
                __DIR__ . '/../../../config/sets/twig/twig127.php'
            ),
            new ComposerTriggeredSet(
                'twig',
                'twig/twig',
                '2.0',
                __DIR__ . '/../../../config/sets/twig/twig20.php'
            ),
            // ...
        ];
    }
}

Setup is straightforward - define the version and path to the set:

namespace Rector\Set\ValueObject;

final class ComposerTriggeredSet
{
    public function __construct(
        private string $groupName,
        private string $packageName,
        private string $version,
        private string $setFilePath
    ) {
    }

    // ...
}

• The $groupName is key in ->withComposerBased():
• The $packageName is the composer package name.
• $version is the minimal version to trigger the set
• and $setFilePath is the path to the Rector config with rules as we know it

In the near future, community packages like Laravel will have their own SetProvider classes. To get their latest upgrade sets, all you'll have to do is add one param:

return RectorConfig::configure()
    ->withComposerBased(laravel: true);

Happy coding!