$ git clone -n https://src.fedoraproject.org/rpms/ghc-NumInstances.git /var/lib/mock/f31-build-53935-27924/root/chroot_tmpdir/scmroot/ghc-NumInstances
Cloning into '/var/lib/mock/f31-build-53935-27924/root/chroot_tmpdir/scmroot/ghc-NumInstances'...
$ git reset --hard fa3c7123cbfa52313d630f9671e6610f8a607395
HEAD is now at fa3c712 refresh to cabal-rpm-0.13