$ git clone -n https://src.fedoraproject.org/rpms/ghc-js-chart.git /var/lib/mock/f38-build-side-42-init-devel-1090892-30049/root/chroot_tmpdir/scmroot/ghc-js-chart
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1090892-30049/root/chroot_tmpdir/scmroot/ghc-js-chart'...
$ git fetch origin 71dd28c9d229742f8fdbcbeae7fb21930d781fa2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-js-chart
 * [new ref]         71dd28c9d229742f8fdbcbeae7fb21930d781fa2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 71dd28c Added the README