$ git clone -n https://src.fedoraproject.org/rpms/perl-JSON-PP.git /var/lib/mock/f43-perl-60964547-6587000/root/chroot_tmpdir/scmroot/perl-JSON-PP
Cloning into '/var/lib/mock/f43-perl-60964547-6587000/root/chroot_tmpdir/scmroot/perl-JSON-PP'...
$ git fetch origin 80c772a1f73292ddde8dc5bda1caf430c6a1f611:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-JSON-PP
 * [new ref]         80c772a1f73292ddde8dc5bda1caf430c6a1f611 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 80c772a Perl 5.42 re-rebuild of bootstrapped packages