$ git clone -n https://src.fedoraproject.org/rpms/rust-group0.13.git /var/lib/mock/f45-build-42169-791/root/chroot_tmpdir/scmroot/rust-group0.13
Cloning into '/var/lib/mock/f45-build-42169-791/root/chroot_tmpdir/scmroot/rust-group0.13'...
$ git fetch origin 4e533b7cd70ff30e232dd53568ee8741e3c9047a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-group0.13
 * [new ref]         4e533b7cd70ff30e232dd53568ee8741e3c9047a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4e533b7 Initial compat package