$ git clone -n https://src.fedoraproject.org/rpms/rust-fixedbitset0.4.git /var/lib/mock/f42-build-3262665-41241/root/chroot_tmpdir/scmroot/rust-fixedbitset0.4
Cloning into '/var/lib/mock/f42-build-3262665-41241/root/chroot_tmpdir/scmroot/rust-fixedbitset0.4'...
$ git fetch origin 4ff665b8852527ff4cba892bfc77955aaea0fbb2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-fixedbitset0.4
 * [new ref]         4ff665b8852527ff4cba892bfc77955aaea0fbb2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4ff665b Initial import (fixedbitset 0.4 compat package)