$ git clone -n https://src.fedoraproject.org/rpms/rust-yaml-rust2.git /var/lib/mock/f45-build-46226-832/root/chroot_tmpdir/scmroot/rust-yaml-rust2
Cloning into '/var/lib/mock/f45-build-46226-832/root/chroot_tmpdir/scmroot/rust-yaml-rust2'...
$ git fetch origin e0e56b003507d90500dd64c554eaf20a829acf04:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-yaml-rust2
 * [new ref]         e0e56b003507d90500dd64c554eaf20a829acf04 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e0e56b0 Update to version 0.10.4