Fixed empty string value for LabelFormat enum property

src/AmazonPHP/SellingPartner/ObjectSerializer.php

@@ -2,6 +2,8 @@
 
 namespace AmazonPHP\SellingPartner;
 
+use AmazonPHP\SellingPartner\Model\MerchantFulfillment\LabelFormat;
+
 final class ObjectSerializer
 {
     private static string $dateTimeFormat = \DateTimeInterface::ATOM;
@@ -374,11 +376,29 @@ public static function deserialize(Configuration $configuration, $data, string $
             }
 
             if (isset($data->{$instance::attributeMap()[$property]})) {
-                $propertyValue = $data->{$instance::attributeMap()[$property]};
+                $propertyValue = self::castEmptyStringToNull($data->{$instance::attributeMap()[$property]}, $type);
+
                 $instance->{$propertySetter}(self::deserialize($configuration, $propertyValue, $type, null));
             }
         }
 
         return $instance;
     }
+
+    /**
+     * @note amazon returns empty string here, which is not a valid enum value
+     * https://github.com/amzn/selling-partner-api-models/issues/226#issuecomment-1075640380
+     *
+     * @param null|array|string $value value that needs to be parsed
+     *
+     * @return null|array|string parsed object property
+     */
+    private static function castEmptyStringToNull($value, string $type)
+    {
+        if ('' === $value && \is_a(LabelFormat::class, $type, true)) {
+            $value = null;
+        }
+
+        return $value;
+    }
 }

tests/AmazonPHP/SellingPartner/Tests/Unit/ObjectSerializerTest.php

@@ -14,6 +14,7 @@
 use AmazonPHP\SellingPartner\Model\FulfillmentInbound\UnitOfMeasurement;
 use AmazonPHP\SellingPartner\Model\FulfillmentInbound\UnitOfWeight;
 use AmazonPHP\SellingPartner\Model\FulfillmentInbound\Weight;
+use AmazonPHP\SellingPartner\Model\MerchantFulfillment\ShippingServiceOptions;
 use AmazonPHP\SellingPartner\ObjectSerializer;
 use PHPUnit\Framework\TestCase;
 
@@ -88,4 +89,24 @@ public function test_serialization_of_object_with_enums(): void
             ObjectSerializer::deserialize($config, $jsonObject, PutTransportDetailsRequest::class)
         );
     }
+
+    public function test_deserialize_label_format_enum_with_an_empty_string(): void
+    {
+        $response = <<<JSON
+{
+    "DeliveryExperience": "DeliveryConfirmationWithoutSignature",
+    "CarrierWillPickUp": false,
+    "LabelFormat": ""
 }
+JSON;
+
+        $object = ObjectSerializer::deserialize(
+            Configuration::forIAMUser('clientId', 'clientSecret', 'accessKey', 'secretKey'),
+            $response,
+            ShippingServiceOptions::class
+        );
+
+        $this->assertInstanceOf(ShippingServiceOptions::class, $object);
+        $this->assertNull($object->getLabelFormat());
+    }
+}