Url of sitemap file is not updated if redirection

[LeMoussel]

In the case of a redirection on the sitemap Url, Url is not updated with the new location.

For example http://cocon.se/sitemap.xml, 301 redirection to http://cocon.se/sitemap_index.xml

let sitemap = new sitemapper({
    url: 'http://cocon.se/sitemap.xml', 
    timeout: 5000 
  });
  sitemap.fetch()
    .then(({ url, sites }) => console.log(`url:${url}`, 'sites:', sites))
    .catch(function (error) {
        loggerConsole.warn(error);
    });

Display

url:http://cocon.se/sitemap.xml sites:
Array(124) ["http://cocon.se", "http://cocon.se/actus/vlc-2015.html", ....

url should be equal to http://cocon.se/sitemap_index.xml