Symfony\Component\DomCrawler\Form::getFiles PHP Method

    public function getFiles()
    {
        if (!in_array($this->getMethod(), array('POST', 'PUT', 'DELETE', 'PATCH'))) {
            return array();
        }

        $files = array();

        foreach ($this->fields->all() as $name => $field) {
            if ($field->isDisabled()) {
                continue;
            }

            if ($field instanceof Field\FileFormField) {
                $files[$name] = $field->getValue();
            }
        }

        return $files;
    }

 protected function makeRequestUsingForm(Form $form)
 {
     $files = [];
     $plainFiles = $form->getFiles();
     foreach ($plainFiles as $key => $file) {
         $files[$key] = new UploadedFile($file['tmp_name'], $file['name'], $file['type'], $file['size'], $file['error'], true);
     }
     return $this->makeRequest($form->getMethod(), $form->getUri(), $form->getValues(), [], $files);
 }