[Capability] Keep a Traversable passed to an iterable parameter

Author: chr-hertel

src/Capability/Registry/ReferenceHandler.php

@@ -247,7 +247,8 @@ private function castArgumentType(mixed $argument, \ReflectionParameter $paramet
                 'string' => (string) $argument,
                 'bool', 'boolean' => $this->castToBoolean($argument),
                 'float', 'double' => $this->castToFloat($argument),
-                'array', 'iterable' => $this->castToArray($argument),
+                'array' => $this->castToArray($argument),
+                'iterable' => $argument instanceof \Traversable ? $argument : $this->castToArray($argument),
                 default => $argument,
             };
         } catch (\TypeError $e) {

tests/Unit/Capability/Registry/ReferenceHandlerTest.php

@@ -174,6 +174,16 @@ public function testParameterTypeDecidesHowJsonObjectsAreDelivered(): void
         $this->assertSame($value, $handler->handle(new ElementReference(static fn ($value) => $value), $context));
     }
 
+    public function testIterableParameterKeepsATraversable(): void
+    {
+        $session = $this->createMock(SessionInterface::class);
+        $session->method('getId')->willReturn(Uuid::v4());
+        $value = new \ArrayIterator(['a' => 1]);
+        $context = ['_session' => $session, '_request' => new PingRequest(), 'value' => $value];
+
+        $this->assertSame($value, (new ReferenceHandler())->handle(new ElementReference(static fn (iterable $value): iterable => $value), $context));
+    }
+
     public function testHandleKeepsTheDefaultOfANonNullableParameterOnAnExplicitNull(): void
     {
         $session = $this->createMock(SessionInterface::class);