Fixed multipart request formatting to preserve array order.

Author: leobedrosian

src/Codeception/Lib/Connector/Guzzle.php

@@ -292,7 +292,7 @@ protected function formatMultipart(mixed $parts, string $key, mixed $value): arr
     {
         if (is_array($value)) {
             foreach ($value as $subKey => $subValue) {
-                $parts = array_merge($this->formatMultipart([], $key . sprintf('[%s]', $subKey), $subValue), $parts);
+                $parts = array_merge($parts, $this->formatMultipart([], $key . sprintf('[%s]', $subKey), $subValue));
             }
 
             return $parts;

tests/data/rest/index.php

@@ -47,6 +47,11 @@
         return [
             'uploaded' => isset($_FILES['file']['tmp_name']) && file_exists($_FILES['file']['tmp_name']),
         ];
+    },
+    'multipart-collections' => function () {
+        return [
+            'body' => $_POST,
+        ];
     }
 ];
 

tests/unit/Codeception/Module/PhpBrowserRestTest.php

@@ -270,6 +270,35 @@ public function testFileUploadWithFilesArray(): void
         ]);
     }
 
+    public function testMultipartPostPreservesArrayOrder(): void
+    {
+        $tmpFileName = tempnam('/tmp', 'test_');
+        file_put_contents($tmpFileName, 'test data');
+        $body = [
+            'users' => [
+                ['id' => 0, 'name' => 'John Doe'],
+                ['id' => 1, 'name' => 'Jane Doe'],
+            ]
+        ];
+        $files = [
+            'file' => [
+                'name' => 'file.txt',
+                'type' => 'text/plain',
+                'size' => 9,
+                'tmp_name' => $tmpFileName,
+            ]
+        ];
+        $this->rest->sendPOST('/rest/multipart-collections', $body, $files);
+        $this->rest->seeResponseEquals(json_encode([
+            'body' => [
+                'users' => [
+                    '0' => ['id' => '0', 'name' => 'John Doe'],
+                    '1' => ['id' => '1', 'name' => 'Jane Doe'],
+                ],
+            ],
+        ]));
+    }
+
     public function testCanInspectResultOfPhpBrowserRequest(): void
     {
         $this->phpBrowser->amOnPage('/rest/user/');