feat: Add state machine dumpers

composer.json

@@ -35,7 +35,8 @@
         "symfony/stopwatch": ">=5.4,<8",
         "symfony/twig-bundle": ">=5.4,<8",
         "symfony/browser-kit": ">=5.4,<8",
-        "symfony/css-selector": ">=5.4,<8"
+        "symfony/css-selector": ">=5.4,<8",
+        "symfony/console": ">=5.4,<8"
     },
     "autoload": {
         "psr-4": {

src/Dumper/Dumper.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Finite\Dumper;
+
+use Finite\State;
+
+interface Dumper
+{
+    /**
+     * @param enum-string<State> $stateEnum
+     */
+    public function dump(string $stateEnum): string;
+}

src/Dumper/MermaidDumper.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace Finite\Dumper;
+
+use Finite\State;
+
+class MermaidDumper implements Dumper
+{
+    /**
+     * @param enum-string<State> $stateEnum
+     */
+    public function dump(string $stateEnum): string
+    {
+        $output = [
+            '---',
+            'title: ' . $stateEnum,
+            '---',
+            'stateDiagram-v2',
+        ];
+
+        foreach ($stateEnum::getTransitions() as $transition) {
+            foreach ($transition->getSourceStates() as $state) {
+                $output[] = sprintf(
+                    '    %s --> %s: %s',
+                    $state->value,
+                    $transition->getTargetState()->value,
+                    $transition->getName()
+                );
+            }
+        }
+
+        return implode(PHP_EOL, $output);
+    }
+}

src/Extension/Symfony/Bundle/FiniteBundle.php

@@ -3,8 +3,14 @@
 
 namespace Finite\Extension\Symfony\Bundle;
 
+use Finite\Extension\Symfony\Command\DumpStateMachineCommand;
+use Symfony\Component\Console\Application;
 use Symfony\Component\HttpKernel\Bundle\Bundle;
 
 final class FiniteBundle extends Bundle
 {
+    public function registerCommands(Application $application): void
+    {
+        $application->add(new DumpStateMachineCommand);
+    }
 }

src/Extension/Symfony/Command/DumpStateMachineCommand.php

@@ -0,0 +1,53 @@
+<?php
+
+namespace Finite\Extension\Symfony\Command;
+
+use Finite\Dumper\MermaidDumper;
+use Finite\State;
+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 Symfony\Component\Console\Style\SymfonyStyle;
+
+final class DumpStateMachineCommand extends Command
+{
+    private const FORMAT_MERMAID = 'mermaid';
+    private const FORMATS = [self::FORMAT_MERMAID];
+
+    protected function configure(): void
+    {
+        $this
+            ->setName('finite:state-machine:dump')
+            ->setDescription('Dump the state machine graph into requested format')
+            ->addArgument('state_enum', InputArgument::REQUIRED, 'The state enum to use')
+            ->addArgument('format', InputArgument::REQUIRED, 'The format to dump the graph in');
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output);
+        $stateEnum = (string)$input->getArgument('state_enum');
+
+        if (!(enum_exists($stateEnum) && is_subclass_of($stateEnum, State::class))) {
+            $io->error('The state enum "' . $stateEnum . '" does not exist.');
+
+            return self::FAILURE;
+        }
+
+        $format = (string)$input->getArgument('format');
+        switch ($format) {
+            case self::FORMAT_MERMAID:
+                /** @psalm-suppress ArgumentTypeCoercion Type is enforced upper but not detected by psalm */
+                $output->writeln((new MermaidDumper)->dump($stateEnum));
+
+                break;
+            default:
+                $output->writeln('Unknown format "' . $format . '". Supported formats are: ' . implode(', ', self::FORMATS));
+
+                return self::FAILURE;
+        }
+
+        return self::SUCCESS;
+    }
+}

src/Transition/Transition.php

@@ -14,9 +14,9 @@ class Transition implements TransitionInterface
 {
     public function __construct(
         public readonly string $name,
-        /** @var State[] */
+        /** @var array<int,State&\BackedEnum> */
         public readonly array $sourceStates,
-        public readonly State $targetState,
+        public readonly State&\BackedEnum $targetState,
         /** @var array<string, string> */
         public readonly array $properties = []
     )
@@ -28,7 +28,7 @@ public function getSourceStates(): array
         return $this->sourceStates;
     }
 
-    public function getTargetState(): State
+    public function getTargetState(): State&\BackedEnum
     {
         return $this->targetState;
     }

src/Transition/TransitionInterface.php

@@ -12,11 +12,11 @@
 interface TransitionInterface
 {
     /**
-     * @return State[]
+     * @return array<int, \BackedEnum&State>
      */
     public function getSourceStates(): array;
 
-    public function getTargetState(): State;
+    public function getTargetState(): State&\BackedEnum;
 
     public function process(object $object): void;
 

tests/Dumper/MermaidDumperTest.php

@@ -0,0 +1,29 @@
+<?php
+
+namespace Finite\Tests\Dumper;
+
+use Finite\Dumper\MermaidDumper;
+use Finite\Tests\E2E\SimpleArticleState;
+use PHPUnit\Framework\TestCase;
+
+class MermaidDumperTest extends TestCase
+{
+    public function test_it_dumps(): void
+    {
+        $this->assertSame(
+            <<<MERMAID
+            ---
+            title: Finite\Tests\E2E\SimpleArticleState
+            ---
+            stateDiagram-v2
+                draft --> published: publish
+                reported --> published: clear
+                disabled --> published: clear
+                published --> reported: report
+                reported --> disabled: disable
+                published --> disabled: disable
+            MERMAID,
+            (new MermaidDumper)->dump(SimpleArticleState::class)
+        );
+    }
+}

tests/Extension/Symfony/Command/DumpStateMachineCommandTest.php

@@ -0,0 +1,59 @@
+<?php
+
+namespace Finite\Tests\Extension\Symfony\Command;
+
+use Finite\Tests\Extension\Symfony\Fixtures\State\DocumentState;
+use Symfony\Bundle\FrameworkBundle\Console\Application;
+use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
+use Symfony\Component\Console\Tester\CommandTester;
+
+class DumpStateMachineCommandTest extends KernelTestCase
+{
+    private ?CommandTester $commandTester = null;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $kernel = self::bootKernel();
+        $application = new Application($kernel);
+
+        $command = $application->find('finite:state-machine:dump');
+        $this->commandTester = new CommandTester($command);
+    }
+
+    public function test_it_returns_mermaid_dump(): void
+    {
+        $this->commandTester->execute([
+            'state_enum' => DocumentState::class,
+            'format' => 'mermaid',
+        ]);
+
+        $this->commandTester->assertCommandIsSuccessful();
+    }
+
+    public function test_it_fails_with_unknown_state_enum(): void
+    {
+        $this->commandTester->execute([
+            'state_enum' => 'UnknownStateEnum',
+            'format' => 'mermaid',
+        ]);
+
+        $this->assertSame(1, $this->commandTester->getStatusCode());
+    }
+
+    public function test_it_fails_with_unknown_format(): void
+    {
+        $this->commandTester->execute([
+            'state_enum' => DocumentState::class,
+            'format' => 'blobfish',
+        ]);
+
+        $this->assertSame(1, $this->commandTester->getStatusCode());
+    }
+
+    protected static function getKernelClass(): string
+    {
+        return \AppKernel::class;
+    }
+}

tests/Transition/TransitionTest.php

@@ -4,6 +4,7 @@
 namespace Finite\Tests\Transition;
 
 use Finite\State;
+use Finite\Tests\E2E\SimpleArticleState;
 use Finite\Transition\Transition;
 use PHPUnit\Framework\TestCase;
 
@@ -13,12 +14,10 @@ class TransitionTest extends TestCase
 
     protected function setUp(): void
     {
-        $targetState = $this->createMock(State::class);
-
         $this->object = new Transition(
             'name',
-            ['source'],
-            $targetState,
+            [SimpleArticleState::DRAFT],
+            SimpleArticleState::PUBLISHED,
             ['property' => 'value', 'property2' => 'value2'],
         );
     }