Comment # 3 on bug 1159195 from Michael Andres

(In reply to Andreas Stieger from comment #2)
> lstat("/var/tmp/zypp.lbz0Ti/zypp-general-krS2i2H9", 0x7fffd1bbada0) = -1
> ENOENT (No such file or directory)
> lstat("/var/tmp/zypp.lbz0Ti/zypp-trusted-kr7jMeie", 0x7fffd1bbada0) = -1
> ENOENT (No such file or directory)

Then please proviede a zypper.log as it happens flawless in my environment.
> zypp-s15sp1:~ (0) $ zypper mr -G Leap15.1-update
> GPG check has been disabled for repository 'Leap15.1-update'.
> zypp-s15sp1:~ (0) $ zypper ref -f Leap15.1-update
> Forcing raw metadata refresh
> Retrieving repository 'Leap15.1-update' metadata [done]
> Forcing building of repository cache
> Building repository 'Leap15.1-update' cache [done]
> Specified repositories have been refreshed.
> 
> zypp-s15sp1:~ (0) $ zypper mr -g Leap15.1-update
> GPG check has been enabled for repository 'Leap15.1-update'.
> zypp-s15sp1:~ (0) $ zypper ref -f Leap15.1-update
> Forcing raw metadata refresh
> Retrieving repository 'Leap15.1-update' metadata [done]
> Forcing building of repository cache
> Building repository 'Leap15.1-update' cache [done]
> Specified repositories have been refreshed.