improve no more middleware exception

Author: DavidBadura

phpstan-baseline.neon

@@ -132,6 +132,12 @@ parameters:
 			count: 2
 			path: src/MetadataHydrator.php
 
+		-
+			message: '#^Strict comparison using \=\=\= between non\-empty\-list\<Patchlevel\\Hydrator\\Middleware\\Middleware\> and array\{\} will always evaluate to false\.$#'
+			identifier: identical.alwaysFalse
+			count: 1
+			path: src/Middleware/Stack.php
+
 		-
 			message: '#^Method Patchlevel\\Hydrator\\Middleware\\TransformMiddleware\:\:hydrate\(\) should return T of object but returns mixed\.$#'
 			identifier: return.type
@@ -186,6 +192,12 @@ parameters:
 			count: 1
 			path: src/Normalizer/ReflectionTypeUtil.php
 
+		-
+			message: '#^Parameter \#2 \$middlewares of class Patchlevel\\Hydrator\\StackHydrator constructor expects non\-empty\-list\<Patchlevel\\Hydrator\\Middleware\\Middleware\>, list\<Patchlevel\\Hydrator\\Middleware\\Middleware\> given\.$#'
+			identifier: argument.type
+			count: 1
+			path: src/StackHydratorBuilder.php
+
 		-
 			message: '#^Property Patchlevel\\Hydrator\\Tests\\Unit\\Extension\\Cryptography\\Fixture\\ChildWithSensitiveDataWithIdentifierDto\:\:\$email is never read, only written\.$#'
 			identifier: property.onlyWritten
@@ -240,6 +252,12 @@ parameters:
 			count: 1
 			path: tests/Unit/MetadataHydratorTest.php
 
+		-
+			message: '#^Parameter \#1 \$middlewares of class Patchlevel\\Hydrator\\Middleware\\Stack constructor expects non\-empty\-list\<Patchlevel\\Hydrator\\Middleware\\Middleware\>, array\{\} given\.$#'
+			identifier: argument.type
+			count: 1
+			path: tests/Unit/Middleware/StackTest.php
+
 		-
 			message: '#^Cannot cast mixed to int\.$#'
 			identifier: cast.int

src/Middleware/MissingMiddlewares.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Patchlevel\Hydrator\Middleware;
+
+use Patchlevel\Hydrator\HydratorException;
+use RuntimeException;
+
+/** @experimental */
+final class MissingMiddlewares extends RuntimeException implements HydratorException
+{
+    public function __construct()
+    {
+        parent::__construct('No middleware available.');
+    }
+}

src/Middleware/NoMoreMiddleware.php

@@ -7,11 +7,23 @@
 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 non-empty-list<Middleware> $middlewares */
+    public function __construct(array $middlewares)
     {
-        parent::__construct('no more middlewares');
+        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

@@ -9,18 +9,21 @@ final class Stack
 {
     private int $index = 0;
 
-    /** @param list<Middleware> $middlewares */
+    /** @param non-empty-list<Middleware> $middlewares */
     public function __construct(
         private readonly array $middlewares,
     ) {
+        if ($middlewares === []) {
+            throw new MissingMiddlewares();
+        }
     }
 
     public function next(): Middleware
     {
         $next = $this->middlewares[$this->index] ?? null;
 
         if ($next === null) {
-            throw new NoMoreMiddleware();
+            throw new NoMoreMiddleware($this->middlewares);
         }
 
         $this->index++;

src/StackHydrator.php

@@ -24,7 +24,7 @@ final class StackHydrator implements HydratorWithContext
     /** @var array<class-string, ClassMetadata> */
     private array $classMetadata = [];
 
-    /** @param list<Middleware> $middlewares */
+    /** @param non-empty-list<Middleware> $middlewares */
     public function __construct(
         private readonly MetadataFactory $metadataFactory = new AttributeMetadataFactory(),
         private readonly array $middlewares = [new TransformMiddleware()],

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 +4,10 @@
 
 namespace Patchlevel\Hydrator\Tests\Unit\Middleware;
 
-use Patchlevel\Hydrator\Middleware\Middleware;
+use Patchlevel\Hydrator\Middleware\MissingMiddlewares;
 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;
 
@@ -15,20 +16,39 @@ final class StackTest extends TestCase
 {
     public function testEmptyStack(): void
     {
-        $this->expectException(NoMoreMiddleware::class);
+        $this->expectException(MissingMiddlewares::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();
+    }
 }

tests/Unit/Middleware/TransformerMiddlewareTest.php

@@ -30,7 +30,7 @@ public function testHydrate(): void
             $this->classMetadata(ProfileCreated::class),
             ['profileId' => '1', 'email' => 'info@patchlevel.de'],
             [],
-            new Stack([]),
+            new Stack([$middleware]),
         );
 
         self::assertEquals($expected, $event);
@@ -49,7 +49,7 @@ public function testExtract(): void
                 Email::fromString('info@patchlevel.de'),
             ),
             [],
-            new Stack([]),
+            new Stack([$middleware]),
         );
 
         self::assertEquals($expected, $data);