$ git clone -n https://src.fedoraproject.org/rpms/rust-gio0.19.git /var/lib/mock/f42-build-side-1-3586830-46926/root/chroot_tmpdir/scmroot/rust-gio0.19
Cloning into '/var/lib/mock/f42-build-side-1-3586830-46926/root/chroot_tmpdir/scmroot/rust-gio0.19'...
$ git fetch origin 1669870156eca5b0be0aae28a5af7e831a10d19e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gio0.19
 * [new ref]         1669870156eca5b0be0aae28a5af7e831a10d19e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1669870 compat package no longer needed