$ git clone -n https://src.fedoraproject.org/rpms/rust-rustcat.git /var/lib/mock/f40-build-2063531-49167/root/chroot_tmpdir/scmroot/rust-rustcat
Cloning into '/var/lib/mock/f40-build-2063531-49167/root/chroot_tmpdir/scmroot/rust-rustcat'...
$ git fetch origin c456f9cefdcb4d365571eee93a0deb09b30ca3b2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rustcat
 * [new ref]         c456f9cefdcb4d365571eee93a0deb09b30ca3b2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c456f9c Bump rustyline dependency to 12