Add a Rector config

.gitignore

@@ -15,4 +15,5 @@ Thumbs.db
 /vendor/**/.git
 /.phpunit.cache
 /.phpstan-tmp
+/.rector-tmp
 /.tools/

phpstan.neon

@@ -25,6 +25,7 @@ parameters:
       - plugins/**/tests/*
       - plugins/*/vendor/intervention/*
       - plugins/*/vendor/psr/log/*
+      - rector.php
       - vendor/**/*
    paths:
       - .

rector.php

@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\Caching\ValueObject\Storage\FileCacheStorage;
+use Rector\Config\RectorConfig;
+
+return RectorConfig::configure()
+	// TODO: use the 'composer.json' approach instead
+	->withPhpSets(php82: true)
+	->withCache(__DIR__ . '/.rector-tmp', FileCacheStorage::class)
+	->withPaths([__DIR__])
+	->withSkip([
+		__DIR__ . '/lib',
+		__DIR__ . '/plugins.local',
+		__DIR__ . '/vendor',
+		// not a fan
+		Rector\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector::class,
+		// noisy at the moment (needs more review)
+		Rector\Php81\Rector\FuncCall\NullToStrictStringFuncCallArgRector::class,
+	]);