Handle deserialization of datetime fields that are empty strings (#875)

Author: jlevers

src/Traits/Deserializes.php

@@ -92,7 +92,7 @@ protected static function deserializeValue(mixed $value, array|string $type): mi
             if (! class_exists($type) && ! interface_exists($type)) {
                 throw new InvalidAttributeTypeException("Neither the Class nor Interface `$type` exists");
             } elseif ($type == DateTimeInterface::class) {
-                if ($value === null) {
+                if ($value === null || $value === '') {
                     return null;
                 }
 

tests/Seller/FBAInventoryV1/Responses/GetInventorySummariesTest.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace SellingPartnerApi\Tests\Seller\FBAInboundV20240320\Responses;
+
+use DateTime;
+use DateTimeInterface;
+use PHPUnit\Framework\TestCase;
+use SellingPartnerApi\Seller\FBAInventoryV1\Responses\GetInventorySummariesResponse;
+
+class GetInventorySummariesTest extends TestCase
+{
+    public function test_deserialize_empty_string_datetime(): void
+    {
+        $result = GetInventorySummariesResponse::deserialize([
+            'payload' => [
+                'granularity' => [
+                    'granularityType' => 'Marketplace',
+                    'granularityId' => 'ATVPDKIKX0DER',
+                ],
+                'inventorySummaries' => [
+                    [
+                        'asin' => 'B000000000',
+                        'fnSku' => '1234567890',
+                        'sellerSku' => '1234567890',
+                        'condition' => 'New',
+                        'lastUpdatedTime' => '',
+                    ]
+                ]
+            ]
+        ]);
+        $this->assertNotNull($result);
+        $this->assertNull($result->payload->inventorySummaries[0]->lastUpdatedTime);
+    }
+}