Refactor the code using Rector

composer.json

@@ -13,6 +13,7 @@
         "phpstan/phpstan": "^1.8",
         "phpstan/phpstan-symfony": "^1.2",
         "phpunit/phpunit": "^10.3",
+        "rector/rector": "^0.18.4",
         "slevomat/coding-standard": ">=6.3.11",
         "squizlabs/php_codesniffer": "^3.5",
         "symfony/process": "^6.0"

rector.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\Config\RectorConfig;
+use Rector\PHPUnit\Set\PHPUnitLevelSetList;
+use Rector\Set\ValueObject\LevelSetList;
+use Rector\Set\ValueObject\SetList;
+use Rector\Symfony\Set\SymfonySetList;
+
+return static function (RectorConfig $rectorConfig): void {
+    $rectorConfig->paths([
+        __DIR__ . '/src',
+        __DIR__ . '/tests',
+    ]);
+
+    $rectorConfig->importNames();
+
+    // register a single rule
+    // $rectorConfig->rule(InlineConstructorDefaultToPropertyRector::class);
+
+    $rectorConfig->sets([
+        LevelSetList::UP_TO_PHP_81,
+        SymfonySetList::ANNOTATIONS_TO_ATTRIBUTES,
+        SetList::CODE_QUALITY,
+        PHPUnitLevelSetList::UP_TO_PHPUNIT_100,
+    ]);
+};

src/ConsoleUnusedStepDefinitionsPrinter.php

@@ -11,19 +11,16 @@
 
 final class ConsoleUnusedStepDefinitionsPrinter implements UnusedStepDefinitionsPrinter
 {
-    private OutputInterface $output;
-
-    public function __construct(OutputInterface $output)
+    public function __construct(private readonly OutputInterface $output)
     {
-        $this->output = $output;
     }
 
     /**
      * @inheritDoc
      */
     public function printUnusedStepDefinitions(array $unusedDefinitions): void
     {
-        if (count($unusedDefinitions) === 0) {
+        if ($unusedDefinitions === []) {
             return;
         }
 

src/UnusedStepDefinitionsChecker.php

@@ -17,29 +17,17 @@
 
 final class UnusedStepDefinitionsChecker implements EventSubscriberInterface
 {
-    private DefinitionFinder $definitionFinder;
-
-    private DefinitionRepository $definitionRepository;
-
-    private UnusedStepDefinitionsPrinter $printer;
-
-    private ?string $filter;
-
     /**
      * @var array<Definition>
      */
     private array $usedDefinitions = [];
 
     public function __construct(
-        DefinitionFinder $definitionFinder,
-        DefinitionRepository $definitionRepository,
-        UnusedStepDefinitionsPrinter $printer,
-        ?string $filter
+        private readonly DefinitionFinder $definitionFinder,
+        private readonly DefinitionRepository $definitionRepository,
+        private readonly UnusedStepDefinitionsPrinter $printer,
+        private readonly ?string $filter
     ) {
-        $this->definitionFinder = $definitionFinder;
-        $this->definitionRepository = $definitionRepository;
-        $this->printer = $printer;
-        $this->filter = $filter;
     }
 
     /**
@@ -76,9 +64,10 @@ public function checkUnusedStepDefinitions(AfterSuiteTested $event): void
         $unusedDefinitions = array_diff($definitions, $this->usedDefinitions);
 
         if ($this->filter) {
-            $unusedDefinitions = array_filter($unusedDefinitions, function (Definition $definition): bool {
-                return (bool) preg_match((string) $this->filter, $definition->getPath());
-            });
+            $unusedDefinitions = array_filter(
+                $unusedDefinitions,
+                fn(Definition $definition): bool => (bool) preg_match((string) $this->filter, $definition->getPath())
+            );
         }
 
         $this->printer->printUnusedStepDefinitions($unusedDefinitions);