Apply rector, phpstan and php-cs-fixer

.drone.yml

@@ -9,22 +9,29 @@ steps:
   - composer install
 
 - name: phpstan
-  image: php:8
+  image: php:8.1
   depends_on:
   - install
   commands:
   - vendor/bin/phpstan analyse
 
+- name: rector
+  image: php:8.1
+  depends_on:
+    - install
+  commands:
+    - vendor/bin/rector process --dry-run
+
 - name: phpunit
-  image: php:8
+  image: php:8.1
   depends_on:
   - install
   commands:
   - vendor/bin/phpunit
 
 - name: style check
-  image: php:8
+  image: php:8.1
   depends_on:
   - install
   commands:
-  - PHP_CS_FIXER_IGNORE_ENV=true vendor/bin/php-cs-fixer fix
+  - vendor/bin/php-cs-fixer fix

.php-cs-fixer.php

@@ -14,7 +14,6 @@ return $config
         'phpdoc_order' => true,
         'ordered_class_elements' => true,
         'multiline_whitespace_before_semicolons' => false,
-        'no_superfluous_phpdoc_tags' => false,
         'phpdoc_annotation_without_dot' => false,
         'phpdoc_types_order' => [
             'null_adjustment' => 'always_last',

Taskfile.yaml

@@ -0,0 +1,54 @@
+# https://taskfile.dev
+
+version: '3'
+
+vars:
+  PHP_IMAGE: php:8.1
+
+tasks:
+  default:
+    cmds:
+      - task --list-all
+    silent: true
+
+  check:
+    cmds:
+      - task: echo_title
+        vars: {TITLE: Running php-cs-fixer...}
+      - task: style
+      - task: echo_title
+        vars: {TITLE: Running phpstan...}
+      - task: phpstan
+      - task: echo_title
+        vars: { TITLE: Running rector... }
+      - task: rector
+      - task: echo_title
+        vars: {TITLE: Running phpunit}
+      - task: phpunit
+
+  style:
+    cmds:
+      - php vendor/bin/php-cs-fixer fix
+    silent: true
+
+  phpstan:
+    cmds:
+      - php vendor/bin/phpstan --configuration=./phpstan.neon analyse
+    silent: true
+
+  rector:
+    cmds:
+      - php vendor/bin/rector process
+    silent: true
+
+  phpunit:
+    cmds:
+      - php vendor/bin/phpunit
+    silent: true
+
+  echo_title:
+    silent: true
+    cmds:
+      - echo ------------------------
+      - echo {{.TITLE}}
+      - echo ------------------------

aoc

@@ -7,11 +7,15 @@ use Symfony\Component\Console\Application;
 use trizz\AdventOfCode\ExecuteDay;
 use trizz\AdventOfCode\Puzzle;
 
-(new CollisionProvider)->register();
+(new CollisionProvider())->register();
 
-$application = new Application();
+$application = new Application('Advent of Code by trizz');
 
 $application->add(new Puzzle());
 $application->add(new ExecuteDay());
 
-$application->run();
+try {
+    $application->run();
+} catch (Exception $e) {
+    echo $e->getMessage();
+}

composer.json

@@ -12,16 +12,17 @@
     "require": {
         "php": "^8.1",
         "ext-mbstring": "*",
-        "symfony/console": "^5",
+        "cebe/markdown": "^1.2",
-        "cebe/markdown": "^1.2"
         "phppkg/cli-markdown": "^2.0",
+        "symfony/console": "^6"
     },
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^3.3",
         "jetbrains/phpstorm-attributes": "^1.0",
-        "nunomaduro/collision": "^5.10",
+        "nunomaduro/collision": "^6",
         "phpstan/phpstan": "^1.2",
         "phpunit/phpunit": "^9.5",
+        "rector/rector": "^0.14.8",
         "symfony/var-dumper": "^6.0"
     },
     "autoload": {
@@ -34,11 +35,6 @@
             "Tests\\": "tests/"
         }
     },
-    "scripts": {
-        "test": "vendor/bin/phpunit",
-        "style": "PHP_CS_FIXER_IGNORE_ENV=true vendor/bin/php-cs-fixer fix",
-        "phpstan": "vendor/bin/phpstan analyse"
-    },
     "config": {
         "sort-packages": true,
         "optimize-autoloader": true

phpstan-baseline.neon

@@ -0,0 +1,56 @@
+parameters:
+	ignoreErrors:
+		-
+			message: "#^Method trizz\\\\AdventOfCode\\\\Y21\\\\Day4\\:\\:arrayHasSingleValue\\(\\) has parameter \\$array with no value type specified in iterable type array\\.$#"
+			count: 1
+			path: src/Y21/Day4.php
+
+		-
+			message: "#^Method trizz\\\\AdventOfCode\\\\Y21\\\\Day4\\:\\:checkCards\\(\\) has parameter \\$cards with no value type specified in iterable type array\\.$#"
+			count: 1
+			path: src/Y21/Day4.php
+
+		-
+			message: "#^Method trizz\\\\AdventOfCode\\\\Y21\\\\Day4\\:\\:checkCards\\(\\) has parameter \\$finishedCards with no value type specified in iterable type array\\.$#"
+			count: 1
+			path: src/Y21/Day4.php
+
+		-
+			message: "#^Parameter \\#1 \\$array of function array_values expects array, array\\<mixed, int\\|false\\>\\|string given\\.$#"
+			count: 1
+			path: src/Y21/Day4.php
+
+		-
+			message: "#^Parameter \\#1 \\$numberList of method trizz\\\\AdventOfCode\\\\Y21\\\\Day4\\:\\:explodeNumbers\\(\\) expects string, array\\<mixed, int\\|false\\>\\|string given\\.$#"
+			count: 1
+			path: src/Y21/Day4.php
+
+		-
+			message: "#^Method trizz\\\\AdventOfCode\\\\Y21\\\\Day6\\:\\:processDay\\(\\) return type has no value type specified in iterable type array\\.$#"
+			count: 1
+			path: src/Y21/Day6.php
+
+		-
+			message: "#^Parameter \\#1 \\$state of method trizz\\\\AdventOfCode\\\\Y21\\\\Day6\\:\\:processDay\\(\\) expects array\\{int\\: int\\}, array given\\.$#"
+			count: 1
+			path: src/Y21/Day6.php
+
+		-
+			message: "#^Method trizz\\\\AdventOfCode\\\\Y21\\\\Day7\\:\\:calculateFuel\\(\\) should return int but returns int\\<0, max\\>\\|false\\.$#"
+			count: 1
+			path: src/Y21/Day7.php
+
+		-
+			message: "#^Method trizz\\\\AdventOfCode\\\\Y21\\\\Day8\\:\\:mapDigits\\(\\) has parameter \\$patterns with no value type specified in iterable type array\\.$#"
+			count: 1
+			path: src/Y21/Day8.php
+
+		-
+			message: "#^Property trizz\\\\AdventOfCode\\\\Y21\\\\Day8\\:\\:\\$digitPatterns type has no value type specified in iterable type array\\.$#"
+			count: 1
+			path: src/Y21/Day8.php
+
+		-
+			message: "#^Property trizz\\\\AdventOfCode\\\\Y21\\\\Day8\\:\\:\\$patternDigits type has no value type specified in iterable type array\\.$#"
+			count: 1
+			path: src/Y21/Day8.php

phpstan.neon

@@ -3,3 +3,6 @@ parameters:
   paths:
     - src
     - tests
+
+includes:
+  - phpstan-baseline.neon

rector.php

@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\CodeQuality\Rector\Class_\InlineConstructorDefaultToPropertyRector;
+use Rector\Config\RectorConfig;
+use Rector\Set\ValueObject\LevelSetList;
+use Rector\Set\ValueObject\SetList;
+
+return static function (RectorConfig $rectorConfig): void {
+    $rectorConfig->paths(
+        [
+            __DIR__.'/src',
+            __DIR__.'/tests',
+        ]
+    );
+
+    // register a single rule
+    $rectorConfig->rule(InlineConstructorDefaultToPropertyRector::class);
+
+    // define sets of rules
+    $rectorConfig->sets(
+        [
+            LevelSetList::UP_TO_PHP_81,
+            SetList::CODE_QUALITY,
+            SetList::CODING_STYLE,
+            SetList::TYPE_DECLARATION_STRICT,
+            SetList::NAMING,
+            SetList::PRIVATIZATION,
+            SetList::EARLY_RETURN,
+        ]
+    );
+};

src/ExecuteDay.php

@@ -7,19 +7,14 @@ use Symfony\Component\Console\Input\InputArgument;
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Output\OutputInterface;
 
-class ExecuteDay extends Command
+final class ExecuteDay extends Command
 {
-    protected int $day;
+    private int $day;
+
+    private int $year;
 
-    protected int $year;
-    /**
-     * @var string The title.
-     */
     private string $title;
 
-    /**
-     * Configure the command.
-     */
     protected function configure(): void
     {
         $this
@@ -29,10 +24,6 @@ class ExecuteDay extends Command
             ->addArgument('year', InputArgument::OPTIONAL, 'The year', date('y'));
     }
 
-    /**
-     * Initializes the command after the input has been bound and before the input
-     * is validated.
-     */
     protected function initialize(InputInterface $input, OutputInterface $output): void
     {
         $this->day = $input->getArgument('day');
@@ -45,14 +36,10 @@ class ExecuteDay extends Command
         $output->writeln(str_repeat('-', strlen($this->title)));
     }
 
-    /**
-     * Executes the current command.
-     *
-     * @return int 0 if everything went fine, or an exit code
-     */
     protected function execute(InputInterface $input, OutputInterface $output): int
     {
         $className = sprintf('%s\\Y%d\\Day%d', __NAMESPACE__, $this->year, $this->day);
+
         /** @var Solution $class */
         $class = new $className();
         $class->loadData();

src/Puzzle.php

@@ -2,25 +2,23 @@
 
 namespace trizz\AdventOfCode;
 
+use PhpPkg\CliMarkdown\CliMarkdown;
 use Symfony\Component\Console\Command\Command;
 use Symfony\Component\Console\Input\InputArgument;
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Output\OutputInterface;
-use trizz\AdventOfCode\Utils\SymfonyConsoleMarkdown;
 
-class Puzzle extends Command
+final class Puzzle extends Command
 {
     protected function configure(): void
     {
         $this
             ->setName('puzzle')
+            ->setDescription('Show the puzzle description.')
             ->addArgument('day', InputArgument::REQUIRED, 'The day number.')
             ->addArgument('year', InputArgument::OPTIONAL, 'The year', date('y'));
     }
 
-    /**
-     * @return int
-     */
     protected function execute(InputInterface $input, OutputInterface $output): int
     {
         $contents = file_get_contents(
@@ -31,7 +29,14 @@ class Puzzle extends Command
                 (int) $input->getArgument('day')
             )
         );
-        $rendered = (new SymfonyConsoleMarkdown())->render($contents);
+
+        if (!$contents) {
+            $output->writeln('Can not read puzzle.');
+
+            return Command::FAILURE;
+        }
+
+        $rendered = (new CliMarkdown())->render($contents);
 
         $output->writeln($rendered);
 

src/Solution.php

@@ -16,12 +16,14 @@ abstract class Solution
 
     /**
      * @var string[] The data to use.
+     *
      * @psalm-suppress PropertyNotSetInConstructor
      */
     public ?array $data = null;
 
     /**
      * @var string[] The example data.
+     *
      * @psalm-suppress PropertyNotSetInConstructor
      */
     public ?array $exampleData = null;
@@ -50,7 +52,7 @@ abstract class Solution
         return 'n/a';
     }
 
-    public function loadData()
+    public function loadData(): void
     {
         $dataFile = sprintf('%s/../data/Y%d/day%d/data.txt', __DIR__, $this->year(), $this->day());
         $dataExampleFile = sprintf('%s/../data/Y%d/day%d/example.txt', __DIR__, $this->year(), $this->day());
@@ -80,16 +82,19 @@ abstract class Solution
         return (int) substr(explode('\\', static::class)[3], 3);
     }
 
-    public function hasData()
+    public function hasData(): bool
     {
         return !empty($this->data);
     }
 
-    public function hasExampleData()
+    public function hasExampleData(): bool
     {
         return !empty($this->exampleData);
     }
 
+    /**
+     * @return array{part1: int|string, part2: int|string}
+     */
     #[ArrayShape(['part1' => 'int|string', 'part2' => 'int|string'])]
     public function results(bool $useExampleData = true): array
     {

src/Utils/Arr.php

@@ -2,7 +2,7 @@
 
 namespace trizz\AdventOfCode\Utils;
 
-class Arr
+final class Arr
 {
     /**
      * Flatten a multi-dimensional array into a single level.
@@ -11,12 +11,11 @@ class Arr
      *
      * @see https://github.com/laravel/framework/blob/c16367a1af68d8f3a1addc1a819f9864334e2c66/src/Illuminate/Collections/Arr.php#L221-L249
      *
-     * @param iterable  $array
+     * @param array<mixed> $array
-     * @param float|int $depth
      *
-     * @return array
+     * @return array<mixed>
      */
-    public static function flatten(iterable $array, float|int $depth = INF)
+    public static function flatten(iterable $array, float|int $depth = INF): array
     {
         $result = [];
 

src/Utils/Str.php

@@ -2,7 +2,7 @@
 
 namespace trizz\AdventOfCode\Utils;
 
-class Str
+final class Str
 {
     /**
      * Check if the entirety of string two matches string one.

src/Y21/Day1.php

@@ -4,12 +4,14 @@ namespace trizz\AdventOfCode\Y21;
 
 use trizz\AdventOfCode\Solution;
 
-class Day1 extends Solution
+final class Day1 extends Solution
 {
     public static int|string|null $part1ExampleResult = 7;
+
     public static int|string|null $part1Result = 1688;
 
     public static int|string|null $part2ExampleResult = 5;
+
     public static int|string|null $part2Result = 1728;
 
     /**

src/Y21/Day2.php

@@ -4,13 +4,15 @@ namespace trizz\AdventOfCode\Y21;
 
 use trizz\AdventOfCode\Solution;
 
-class Day2 extends Solution
+final class Day2 extends Solution
 {
     public static int|string|null $part1ExampleResult = 150;
-    public static int|string|null $part1Result = 1654760;
+
+    public static int|string|null $part1Result = 1_654_760;
 
     public static int|string|null $part2ExampleResult = 900;
-    public static int|string|null $part2Result = 1956047400;
+
+    public static int|string|null $part2Result = 1_956_047_400;
 
     /**
      * {@inheritdoc}

src/Y21/Day3.php

@@ -4,10 +4,11 @@ namespace trizz\AdventOfCode\Y21;
 
 use trizz\AdventOfCode\Solution;
 
-class Day3 extends Solution
+final class Day3 extends Solution
 {
     public static int|string|null $part1ExampleResult = 198;
-    public static int|string|null $part1Result = 3309596;
+
+    public static int|string|null $part1Result = 3_309_596;
 
     /**
      * {@inheritdoc}
@@ -27,9 +28,9 @@ class Day3 extends Solution
         $gammaRate = '';
         $epsilonRate = '';
 
-        foreach ($bits as $values) {
+        foreach ($bits as $bit) {
-            $zeros = array_filter($values, static fn ($value) => $value === '0');
+            $zeros = array_filter($bit, static fn ($value) => $value === '0');
-            $ones = array_filter($values, static fn ($value) => $value === '1');
+            $ones = array_filter($bit, static fn ($value) => $value === '1');
 
             $gammaRate .= ($ones > $zeros) ? '1' : '0';
             $epsilonRate .= ($ones < $zeros) ? '1' : '0';

src/Y21/Day4.php

@@ -4,12 +4,14 @@ namespace trizz\AdventOfCode\Y21;
 
 use trizz\AdventOfCode\Solution;
 
-class Day4 extends Solution
+final class Day4 extends Solution
 {
     public static int|string|null $part1ExampleResult = 4512;
+
     public static int|string|null $part1Result = 60368;
 
     public static int|string|null $part2ExampleResult = 1924;
+
     public static int|string|null $part2Result = 17435;
 
     /**
@@ -30,15 +32,13 @@ class Day4 extends Solution
 
     /**
      * @param int[] $winningCard
-     * @param int   $number
-     * @psalm-param array<int, array<array-key, bool|int>|string> $winningCard
      *
-     * @return int
+     * @psalm-param array<int, array<array-key, bool|int>|string> $winningCard
      */
-    protected function calculateScore(array $winningCard, int $number): int
+    private function calculateScore(array $winningCard, int $number): int
     {
         $return = [];
-        array_walk_recursive($winningCard, static function (bool $value, int $key) use (&$return) {
+        array_walk_recursive($winningCard, static function (bool $value, int $key) use (&$return): void {
             $return[$key] = $value;
         });
         $unusedNumbers = array_keys(array_filter($return, static fn (bool $value) => !$value));
@@ -47,14 +47,13 @@ class Day4 extends Solution
     }
 
     /**
-     * @param string $numberList
+     * @param non-empty-string $separator
-     * @param string $separator
      *
      * @return int[]
      *
      * @psalm-return array<int, int>
      */
-    protected function explodeNumbers(string $numberList, string $separator): array
+    private function explodeNumbers(string $numberList, string $separator): array
     {
         return array_map(
             static fn ($value) => (int) $value,
@@ -67,13 +66,10 @@ class Day4 extends Solution
 
     /**
      * @param string[] $data
-     * @param bool     $firstWins
-     *
-     * @return int|string
      */
-    protected function playBingo(array $data, bool $firstWins = true): int|string
+    private function playBingo(array $data, bool $firstWins = true): int|string
     {
-        $numbers = $this->explodeNumbers(array_shift($data), ',');
+        $numbers = $this->explodeNumbers(array_shift($data) ?? '', ',');
         $cards = $this->setupCards($data);
         $finishedCards = [];
 
@@ -129,7 +125,7 @@ class Day4 extends Solution
      *
      * @psalm-return array<int, array<int, array<false|int>|string>>
      */
-    protected function setupCards(array $data): array
+    private function setupCards(array $data): array
     {
         $cards = array_chunk($data, 5);
         foreach ($cards as $card => $rows) {
@@ -148,7 +144,7 @@ class Day4 extends Solution
      *
      * @psalm-return list<int>
      */
-    protected function checkCards(array $cards, array $finishedCards): array
+    private function checkCards(array $cards, array $finishedCards): array
     {
         $winningCards = [];
         // Check rows
@@ -191,7 +187,7 @@ class Day4 extends Solution
         return $winningCards;
     }
 
-    protected function arrayHasSingleValue(array $array, bool $value): bool
+    private function arrayHasSingleValue(array $array, bool $value): bool
     {
         return count(array_unique($array)) === 1 && end($array) === $value;
     }

src/Y21/Day6.php

@@ -5,20 +5,22 @@ namespace trizz\AdventOfCode\Y21;
 use JetBrains\PhpStorm\Immutable;
 use trizz\AdventOfCode\Solution;
 
-class Day6 extends Solution
+final class Day6 extends Solution
 {
     public static int|string|null $part1ExampleResult = 5934;
+
     public static int|string|null $part1Result = 350917;
 
-    public static int|string|null $part2ExampleResult = 26984457539;
+    public static int|string|null $part2ExampleResult = 26_984_457_539;
-    public static int|string|null $part2Result = 1592918715629;
+
+    public static int|string|null $part2Result = 1_592_918_715_629;
 
     /**
      * @var int[]
+     *
      * @psalm-param array{int: int}
      */
-    #[Immutable]
+    #[Immutable] private array $startState = [
-    protected array $startState = [
         8 => 0,
         7 => 0,
         6 => 0,
@@ -48,11 +50,10 @@ class Day6 extends Solution
 
     /**
      * @param int[] $state
-     * @psalm-param array{int: int} $state
      *
-     * @return array
+     * @psalm-param array{int: int} $state
      */
-    protected function processDay(array $state): array
+    private function processDay(array $state): array
     {
         $newState = $state;
 
@@ -75,11 +76,11 @@ class Day6 extends Solution
         return $newState;
     }
 
-    protected function processPuzzle(int $numberOfDays, string $data): int
+    private function processPuzzle(int $numberOfDays, string $data): int
     {
         $state = $this->startState;
 
-        array_map(static function (string $stateValue) use (&$state) {
+        array_map(static function (string $stateValue) use (&$state): void {
             ++$state[(int) $stateValue];
         }, explode(',', $data));
 

src/Y21/Day7.php

@@ -4,13 +4,15 @@ namespace trizz\AdventOfCode\Y21;
 
 use trizz\AdventOfCode\Solution;
 
-class Day7 extends Solution
+final class Day7 extends Solution
 {
     public static int|string|null $part1ExampleResult = 37;
+
     public static int|string|null $part1Result = 344297;
 
     public static int|string|null $part2ExampleResult = 168;
-    public static int|string|null $part2Result = 97164301;
+
+    public static int|string|null $part2Result = 97_164_301;
 
     /**
      * {@inheritdoc}
@@ -28,15 +30,10 @@ class Day7 extends Solution
         return $this->calculateFuel($data[0], forPart2: true);
     }
 
-    /**
+    private function calculateFuel(string $data, bool $forPart2 = false): int
-     * @param string $data
-     * @param bool   $forPart2
-     *
-     * @return int
-     */
-    protected function calculateFuel(string $data, bool $forPart2 = false): int
     {
         $crabs = array_map(static fn (string $crab) => (int) $crab, explode(',', $data));
+
         /** @psalm-param array{int: int} $fuelPerPosition */
         $fuelPerPosition = [];
 

src/Y21/Day8.php

@@ -6,7 +6,7 @@ use trizz\AdventOfCode\Solution;
 use trizz\AdventOfCode\Utils\Arr;
 use trizz\AdventOfCode\Utils\Str;
 
-class Day8 extends Solution
+final class Day8 extends Solution
 {
     public static int|string|null $part1ExampleResult = 26;
 
@@ -14,7 +14,7 @@ class Day8 extends Solution
 
     public static int|string|null $part2ExampleResult = 61229;
 
-    public static int|string|null $part2Result = 1027422;
+    public static int|string|null $part2Result = 1_027_422;
 
     private array $digitPatterns;
 
@@ -26,7 +26,7 @@ class Day8 extends Solution
     public function part1(array $data): int
     {
         $values = array_map(
-            static fn ($item) => strlen($item),
+            static fn ($item) => strlen((string) $item),
             Arr::flatten(
                 array_map(
                     static fn ($item) => explode(' ', $item),
@@ -48,8 +48,8 @@ class Day8 extends Solution
         foreach ($data as $line) {
             $item = explode(' | ', $line);
             $sequences[] = [
-                'patterns' => array_map([Str::class, 'sort'], explode(' ', $item[0])),
+                'patterns' => array_map(Str::sort(...), explode(' ', $item[0])),
-                'shown' => array_map([Str::class, 'sort'], explode(' ', $item[1])),
+                'shown' => array_map(Str::sort(...), explode(' ', $item[1])),
             ];
         }
 

tests/SolutionsTest.php

@@ -2,56 +2,84 @@
 
 namespace Tests;
 
-use trizz\AdventOfCode\ExecuteDay;
 use PHPUnit\Framework\TestCase;
 use trizz\AdventOfCode\Solution;
 
-class SolutionsTest extends TestCase
+/**
+ * @internal
+ */
+final class SolutionsTest extends TestCase
 {
     /**
      * @dataProvider loadSolutions
      */
-    public function testSolutionPart1Example(Solution $class): void
+    public function testSolutionPart1Example(Solution $solution): void
     {
-        $this->runPart($class, part: 1, testExample: true);
+        $this->runPart($solution, part: 1, testExample: true);
     }
 
     /**
      * @dataProvider loadSolutions
+     *
      * @depends testSolutionPart1Example
      */
-    public function testSolutionPart1(Solution $class): void
+    public function testSolutionPart1(Solution $solution): void
     {
-        $this->runPart($class, part: 1, testExample: false);
+        $this->runPart($solution, part: 1, testExample: false);
     }
 
     /**
      * @dataProvider loadSolutions
+     *
      * @depends testSolutionPart1
      */
-    public function testSolutionPart2Example(Solution $class): void
+    public function testSolutionPart2Example(Solution $solution): void
     {
-        $this->runPart($class, part: 2, testExample: true);
+        $this->runPart($solution, part: 2, testExample: true);
     }
 
     /**
      * @dataProvider loadSolutions
+     *
      * @depends testSolutionPart2Example
      */
-    public function testSolutionPart2(Solution $class): void
+    public function testSolutionPart2(Solution $solution): void
     {
-        $this->runPart($class, part: 2, testExample: false);
+        $this->runPart($solution, part: 2, testExample: false);
     }
 
-    private function runPart(Solution $class, int $part, bool $testExample): void
+    /**
+     * @return array<string, array<int, Solution>>
+     */
+    public function loadSolutions(): array
+    {
+        $classes = [];
+        for ($year = 15; $year <= date('y'); ++$year) {
+            if (is_dir(__DIR__.'/../src/Y'.$year)) {
+                for ($day = 1; $day < 26; ++$day) {
+                    $className = sprintf('trizz\\AdventOfCode\\Y%d\\Day%d', $year, $day);
+                    if (class_exists($className)) {
+                        /** @var Solution $class */
+                        $class = new $className();
+                        $class->loadData();
+                        $classes["Year '".$year.' / Day '.$day] = [$class];
+                    }
+                }
+            }
+        }
+
+        return $classes;
+    }
+
+    private function runPart(Solution $solution, int $part, bool $testExample): void
     {
         if (
-            ($testExample && $class->hasExampleData())
+            ($testExample && $solution->hasExampleData())
-            || (!$testExample && $class->hasData())
+            || (!$testExample && $solution->hasData())
         ) {
-            $expectedResult = $class::${'part'.$part.($testExample ? 'Example' : null).'Result'};
+            $expectedResult = $solution::${'part'.$part.($testExample ? 'Example' : null).'Result'};
             if ($expectedResult) {
-                $result = $class->{'part'.$part.'Data'}(useExampleData: $testExample);
+                $result = $solution->{'part'.$part.'Data'}(useExampleData: $testExample);
                 self::assertSame($expectedResult, $result);
             } else {
                 $this->markTestSkipped('No '.($testExample ? 'example' : 'expected').' data for part '.$part.'.');
@@ -60,23 +88,4 @@ class SolutionsTest extends TestCase
             $this->markTestSkipped('No example and expected data for part '.$part.'.');
         }
     }
-
-    public function loadSolutions(): array
-    {
-        $classes = [];
-        for ($year = 15; $year <= date('y'); $year++) {
-            if (is_dir(__DIR__.'/../src/Y'.$year)) {
-                for ($day = 1; $day < 26; $day++) {
-                    $className = sprintf("trizz\\AdventOfCode\\Y%d\\Day%d", $year, $day);
-                    if (class_exists($className)) {
-                        $class = new $className();
-                        $class->loadData();
-                        $classes['Year \''.$year.' / Day '.$day] = [$class];
-                    }
-                }
-            }
-        }
-
-        return $classes;
-    }
 }