$ git clone -n https://src.fedoraproject.org/rpms/rust-cargo_metadata0.18.git /var/lib/mock/f42-build-3253026-41225/root/chroot_tmpdir/scmroot/rust-cargo_metadata0.18
Cloning into '/var/lib/mock/f42-build-3253026-41225/root/chroot_tmpdir/scmroot/rust-cargo_metadata0.18'...
$ git fetch origin 1062d538d0acfd80156afc796c5a63c375c44d63:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-cargo_metadata0.18
 * [new ref]         1062d538d0acfd80156afc796c5a63c375c44d63 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1062d53 Initial import (cargo_metadata 0.18 compat package)