$ git clone -n https://src.fedoraproject.org/rpms/ghc-formatting.git /var/lib/mock/f41-build-839413-160145/root/chroot_tmpdir/scmroot/ghc-formatting
Cloning into '/var/lib/mock/f41-build-839413-160145/root/chroot_tmpdir/scmroot/ghc-formatting'...
$ git fetch origin ae37609cd5d96e46e1055091677c061c728c9de1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-formatting
 * [new ref]         ae37609cd5d96e46e1055091677c061c728c9de1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ae37609 disable double-conversion