improve no more middleware exception

Author: DavidBadura

src/Middleware/NoMoreMiddleware.php

@@ -7,11 +7,29 @@
 use Patchlevel\Hydrator\HydratorException;
 use RuntimeException;
 
+use function array_map;
+use function count;
+use function implode;
+use function sprintf;
+
 /** @experimental */
 final class NoMoreMiddleware extends RuntimeException implements HydratorException
 {
-    public function __construct()
+    /** @param list<Middleware> $middlewares */
+    public function __construct(array $middlewares)
     {
-        parent::__construct('no more middlewares');
+        if ($middlewares === []) {
+            parent::__construct('No middleware available.');
+
+            return;
+        }
+
+        parent::__construct(
+            sprintf(
+                'The next middleware in %s was requested, but no further middleware exists. The following middlewares were executed: %s',
+                $middlewares[count($middlewares) - 1]::class,
+                implode(', ', array_map(static fn (Middleware $middleware): string => $middleware::class, $middlewares)),
+            ),
+        );
     }
 }

src/Middleware/Stack.php

@@ -20,7 +20,7 @@ public function next(): Middleware
         $next = $this->middlewares[$this->index] ?? null;
 
         if ($next === null) {
-            throw new NoMoreMiddleware();
+            throw new NoMoreMiddleware($this->middlewares);
         }
 
         $this->index++;

tests/Unit/Fixture/DummyMiddleware.php

@@ -0,0 +1,36 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Patchlevel\Hydrator\Tests\Unit\Fixture;
+
+use Patchlevel\Hydrator\Metadata\ClassMetadata;
+use Patchlevel\Hydrator\Middleware\Middleware;
+use Patchlevel\Hydrator\Middleware\Stack;
+
+final class DummyMiddleware implements Middleware
+{
+    /**
+     * @param ClassMetadata<T>     $metadata
+     * @param array<string, mixed> $data
+     * @param array<string, mixed> $context
+     *
+     * @return T
+     *
+     * @template T of object
+     */
+    public function hydrate(ClassMetadata $metadata, array $data, array $context, Stack $stack): object
+    {
+        return $stack->next()->hydrate($metadata, $data, $context, $stack);
+    }
+
+    /**
+     * @param array<string, mixed> $context
+     *
+     * @return array<string, mixed>
+     */
+    public function extract(ClassMetadata $metadata, object $object, array $context, Stack $stack): array
+    {
+        return $stack->next()->extract($metadata, $object, $context, $stack);
+    }
+}

tests/Unit/Middleware/StackTest.php

@@ -4,9 +4,9 @@
 
 namespace Patchlevel\Hydrator\Tests\Unit\Middleware;
 
-use Patchlevel\Hydrator\Middleware\Middleware;
 use Patchlevel\Hydrator\Middleware\NoMoreMiddleware;
 use Patchlevel\Hydrator\Middleware\Stack;
+use Patchlevel\Hydrator\Tests\Unit\Fixture\DummyMiddleware;
 use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\TestCase;
 
@@ -16,19 +16,38 @@ final class StackTest extends TestCase
     public function testEmptyStack(): void
     {
         $this->expectException(NoMoreMiddleware::class);
+        $this->expectExceptionMessage('No middleware available.');
 
         $stack = new Stack([]);
         $stack->next();
     }
 
     public function testStack(): void
     {
-        $middleware1 = $this->createStub(Middleware::class);
-        $middleware2 = $this->createStub(Middleware::class);
+        $middleware1 = new DummyMiddleware();
+        $middleware2 = new DummyMiddleware();
 
         $stack = new Stack([$middleware1, $middleware2]);
 
         self::assertSame($middleware1, $stack->next());
         self::assertSame($middleware2, $stack->next());
     }
+
+    public function testStackThrowsExceptionWhenNoMoreMiddlewareIsAvailable(): void
+    {
+        $middleware1 = new DummyMiddleware();
+        $middleware2 = new DummyMiddleware();
+
+        $stack = new Stack([$middleware1, $middleware2]);
+
+        $stack->next();
+        $stack->next();
+
+        $this->expectException(NoMoreMiddleware::class);
+        $this->expectExceptionMessage(
+            'The next middleware in Patchlevel\Hydrator\Tests\Unit\Fixture\DummyMiddleware was requested, but no further middleware exists. The following middlewares were executed: Patchlevel\Hydrator\Tests\Unit\Fixture\DummyMiddleware, Patchlevel\Hydrator\Tests\Unit\Fixture\DummyMiddleware',
+        );
+
+        $stack->next();
+    }
 }