fix: backported #47914 (#47919)

Author: ImJustToNy

src/Illuminate/Http/Request.php

@@ -12,7 +12,6 @@
 use RuntimeException;
 use Symfony\Component\HttpFoundation\Exception\SessionNotFoundException;
 use Symfony\Component\HttpFoundation\InputBag;
-use Symfony\Component\HttpFoundation\ParameterBag;
 use Symfony\Component\HttpFoundation\Request as SymfonyRequest;
 use Symfony\Component\HttpFoundation\Session\SessionInterface;
 
@@ -404,7 +403,7 @@ public function get(string $key, mixed $default = null): mixed
     public function json($key = null, $default = null)
     {
         if (! isset($this->json)) {
-            $this->json = new ParameterBag((array) json_decode($this->getContent(), true));
+            $this->json = new InputBag((array) json_decode($this->getContent(), true));
         }
 
         if (is_null($key)) {
@@ -488,7 +487,7 @@ public static function createFromBase(SymfonyRequest $request)
         $newRequest->content = $request->content;
 
         if ($newRequest->isJson()) {
-            $newRequest->request = new InputBag($newRequest->json()->all());
+            $newRequest->request = $newRequest->json();
         }
 
         return $newRequest;

tests/Http/HttpRequestTest.php

@@ -1574,4 +1574,34 @@ public function testGeneratingJsonRequestFromParentRequestUsesCorrectType()
         $this->assertInstanceOf(InputBag::class, $request->getPayload());
         $this->assertSame('world', $request->getPayload()->get('hello'));
     }
+
+    public function testJsonRequestsCanMergeDataIntoJsonRequest()
+    {
+        if (! method_exists(SymfonyRequest::class, 'getPayload')) {
+            return;
+        }
+
+        $base = SymfonyRequest::create('/', 'POST', server: ['CONTENT_TYPE' => 'application/json'], content: '{"first":"Taylor","last":"Otwell"}');
+        $request = Request::createFromBase($base);
+
+        $request->merge([
+            'name' => $request->get('first').' '.$request->get('last'),
+        ]);
+
+        $this->assertSame('Taylor Otwell', $request->get('name'));
+    }
+
+    public function testItCanHaveObjectsInJsonPayload()
+    {
+        if (! method_exists(SymfonyRequest::class, 'getPayload')) {
+            return;
+        }
+
+        $base = SymfonyRequest::create('/', 'POST', server: ['CONTENT_TYPE' => 'application/json'], content: '{"framework":{"name":"Laravel"}}');
+        $request = Request::createFromBase($base);
+
+        $value = $request->get('framework');
+
+        $this->assertSame(['name' => 'Laravel'], $request->get('framework'));
+    }
 }