bug#25020: guix refresh does not discover updates if URLs are "non-standard"

[Glenn Morris <rgm@gnu.org>]

This was sent to submit@debbugs with no Package: specified and so ended
up on the help-debbugs list. I have reassigned it to guix.

Hartmut Goebel wrote:

> Hi,
>
> I just updated kde-frameworks to 5.28 and found that not all updates
> have been discovered.
>
> Those where the URL is following the standard schema where found:
> "mirror://kde/stable/frameworks/" (version-major+minor version) "/" name
> "-" version ".tar.xz"))
>
> Those having a different name of the archive or having an additional
> directory behind the first version-part have not been found.
>
> Update found for:
>
>     (name "extra-cmake-modules")
>     (version "5.27.0")
>     (source (origin
>               (method url-fetch)
>               (uri (string-append
>                     "mirror://kde/stable/frameworks/"
>                     (version-major+minor version) "/"
>                     name "-" version ".tar.xz"))
>
> Update not found for (archive-name has "5" appended):
>
>     (name "oxygen-icons")
>     (version "5.27.0")
>     (source (origin
>               (method url-fetch)
>               (uri (string-append
>                     "mirror://kde/stable/frameworks/"
>                     (version-major+minor version) "/"
>                     name "5" "-" version ".tar.xz"))
>
> Update not found for (additional directory level):
>
>     (name "kross")
>     (version "5.27.0")
>     (source
>      (origin
>        (method url-fetch)
>        (uri (string-append
>              "mirror://kde/stable/frameworks/"
>              (version-major+minor version) "/portingAids/"
>              name "-" version ".tar.xz"))