Follow up to #5976

Packages that ship lot of versions, can have lot of sets to apply. E.g. twig/twig has 6 sets in Rector, couple for v1 and couple for v2. At the moment, those sets have to be added manually to run.

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 is wrong for couple 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 sets - they also may cause 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, 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. We should not maintain the rector.php at all.

Introducing withComposerBased() 🎉

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

Rector will go through all Twig sets, check our installed version and apply only sets relevant to our specific version ✔️