$ git clone -n https://src.fedoraproject.org/rpms/rust-cairo-rs0.19.git /var/lib/mock/f42-build-side-1-3504285-45983/root/chroot_tmpdir/scmroot/rust-cairo-rs0.19
Cloning into '/var/lib/mock/f42-build-side-1-3504285-45983/root/chroot_tmpdir/scmroot/rust-cairo-rs0.19'...
$ git fetch origin 8d539fdc4a67b4e6a024928bb048a04c6e6a78dd:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-cairo-rs0.19
 * [new ref]         8d539fdc4a67b4e6a024928bb048a04c6e6a78dd -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8d539fd compat package no longer needed