ApiPlatform\Core\Util\RequestParser::parseAndDuplicateRequest PHP Method

    public static function parseAndDuplicateRequest(Request $request) : Request
    {
        $query = self::parseRequestParams($request->getQueryString() ?? '');
        $body = self::parseRequestParams($request->getContent());
        return $request->duplicate($query, $body);
    }

 public function testParseAndDupplicateRequest()
 {
     $request = new Request(['toto=tata'], [], [], [], [], [], '{"gerard":"toto"}');
     $value = RequestParser::parseAndDuplicateRequest($request);
     $this->assertNotNull($value);
 }