Previously, 'guix refresh --update' would do actually rewrite the file with
the same version/hash information when the target version was the same as the
current version:
guix refresh --update idutils=4.6
idutils.scm: warning: downgrading 'idutils' from 4.6 to 4.6
[...]
idutils.scm: idutils: updating from version 4.6 to version 4.6...
This changes handles this case so that it does and prints nothing.
* guix/upstream.scm (package-update): Use `version-compare' to distinguish the
equal versions case.
Change-Id: I079e030d573f5968725ef13b3f626e2f8d02cb2f
Signed-off-by: Christopher Baines <mail@cbaines.net>