$ git clone -n https://src.fedoraproject.org/rpms/rust-smallvec.git /var/lib/mock/f45-build-45048-820/root/chroot_tmpdir/scmroot/rust-smallvec
Cloning into '/var/lib/mock/f45-build-45048-820/root/chroot_tmpdir/scmroot/rust-smallvec'...
$ git fetch origin 59c637af536889bd1319f27fa87a805f61a69123:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-smallvec
 * [new ref]         59c637af536889bd1319f27fa87a805f61a69123 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 59c637a Update to version 1.16.1; Fixes RHBZ#2531887