$ git clone -n https://src.fedoraproject.org/rpms/rust-zcheapstr.git /var/lib/mock/f45-build-46343-833/root/chroot_tmpdir/scmroot/rust-zcheapstr
Cloning into '/var/lib/mock/f45-build-46343-833/root/chroot_tmpdir/scmroot/rust-zcheapstr'...
$ git fetch origin e5dc4a85d2e22ff5be4618f155ba984782f562d9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-zcheapstr
 * [new ref]         e5dc4a85d2e22ff5be4618f155ba984782f562d9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e5dc4a8 Initial import (RHBZ#2538706)