$ git clone -n https://src.fedoraproject.org/rpms/rust-ref-cast.git /var/lib/mock/f45-build-44429-813/root/chroot_tmpdir/scmroot/rust-ref-cast
Cloning into '/var/lib/mock/f45-build-44429-813/root/chroot_tmpdir/scmroot/rust-ref-cast'...
$ git fetch origin a2624f0584768000499e479fe022cfe4a8c2135e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-ref-cast
 * [new ref]         a2624f0584768000499e479fe022cfe4a8c2135e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a2624f0 Update to version 1.0.27; Fixes RHBZ#2502112