src/Http/RequestStaticTrait.php
public static function hasFile($key = null)
    {
        return func_num_args() ? Arr::has($_FILES, $key) : (bool) $_FILES;
    }
public static function hasFile($key = null)
    {
        return func_num_args() ? Arr::has($_FILES, $key) : (bool) $_FILES;
    }
$_FILES