$ git clone -n https://src.fedoraproject.org/rpms/dolfin.git /var/lib/mock/f42-build-864949-172672/root/chroot_tmpdir/scmroot/dolfin
Cloning into '/var/lib/mock/f42-build-864949-172672/root/chroot_tmpdir/scmroot/dolfin'...
$ git fetch origin 280c96a89b8d405cd853684db4f9cd2b7bcd8ac5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/dolfin
 * [new ref]         280c96a89b8d405cd853684db4f9cd2b7bcd8ac5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 280c96a Add missing runtime dependency