anchor.diff:      true = ensure_new_tx(N2, NewTx).
   
   ensure_tx_pools_empty(Config) ->
  +    ensure_tx_pools_n_txs_(Config, 0).
  +
  +ensure_tx_pools_one_tx(Config) ->
  +    ensure_tx_pools_n_txs_(Config, 1).
  +
  +ensure_tx_pools_n_txs_(Config, TxsCount) ->
       Ns = [N || {_,N} <- ?config(nodes, Config)],
       retry(
         fun() ->
  -              Results = lists:map(
  -                          fun(N) ->
  -                                  {ok, Pool} = get_pool(N),
  -                                  ct:log("Pool (~p) = ~p", [N, Pool]),
  -                                  Pool
  -                          end, Ns),
  -              lists:all(fun([]) -> true;
  -                           (_)  -> false
  -                        end, Results)
  -      end, {?LINE, ensure_tx_pools_empty, Ns}).
  +              [APool | RestPools] =
  +                  lists:map(
  +                    fun(N) ->
  +                            case get_pool(N) of
  +                                {ok, Pool} when is_list(Pool) ->
  +                                    ct:log("Pool (~p) = ~p", [N, Pool]),
  +                                    Pool
  +                            end
  +                    end, Ns),
  +              if
  +                  length(APool) =:= TxsCount ->
  +                      lists:all(fun(P) when P =:= APool -> true;
  +                                   (_) -> false
  +                                end, RestPools);
  +                  true ->
  +                      false
  +              end
  +      end, {?LINE, ensure_tx_pools_n_txs_, TxsCount, Ns}).
   
   no_system_metrics_logged(Config) ->
       %% a user config filter is applied in init_per_suite, which turns off
  
positive.code:     [
       {all_nodes, [sequence], [{group, two_nodes},
                                {group, three_nodes},
                                {group, one_blocked}]},
       {two_nodes, [sequence],
        [start_first_node,
  
negative.code:        mine_on_third,
         restart_third,
         no_system_metrics_logged]},
       {semantically_invalid_tx, [sequence],
        [start_first_node,
         start_second_node,
         ensure_tx_pools_empty,
         tx_first_pays_second_more_it_can_afford,
         mine_on_second,
         ensure_tx_pools_one_tx]},
       {one_blocked, [sequence],
        [start_first_node,
         mine_on_first,
         start_blocked_second]}
      ].
  
  suite() ->
  