$ git clone -n https://src.fedoraproject.org/rpms/rust-sinit.git /var/lib/mock/f45-build-44983-820/root/chroot_tmpdir/scmroot/rust-sinit
Cloning into '/var/lib/mock/f45-build-44983-820/root/chroot_tmpdir/scmroot/rust-sinit'...
$ git fetch origin 3c8c0e36f06447397d07b1402683e577e64bf6a3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-sinit
 * [new ref]         3c8c0e36f06447397d07b1402683e577e64bf6a3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3c8c0e3 Regenerate with rust2rpm v28