anchor.diff:      {[{failover, b}], _} = process_frame([a,b,c], [b], State2).
   
   other_down_test() ->
  -    State0 = init_state(3),
  +    State0 = init_state(3+?DOWN_GRACE_PERIOD),
       {[], State1} = process_frame([a,b,c], [b], State0),
       State2 = process_frame_no_action(3, [a,b,c], [b], State1),
       {[{mail_down_warning, _}], State3} = process_frame([a,b,c], [b,c], State2),
  
positive.code:     process_frame_no_action(Times-1, Nodes, DownNodes, NewState).
  
  basic_1_test() ->
      State0 = init_state(3),
      {[], State1} = process_frame([a,b,c], [], State0),
      State2 = process_frame_no_action(4, [a,b,c], [b], State1),
      {[{failover, b}], _} = process_frame([a,b,c], [b], State2).
  
  basic_2_test() ->
      State0 = init_state(4),
      {[], State1} = process_frame([a,b,c], [b], State0),
      State2 = process_frame_no_action(4, [a,b,c], [b], State1),
      {[{failover, b}], _} = process_frame([a,b,c], [b], State2).
  
  min_size_test_body(Threshold) ->
      State0 = init_state(Threshold),
      {[], State1} = process_frame([a,b], [b], State0),
      State2 = process_frame_no_action(Threshold, [a,b], [b], State1),
      {[{mail_too_small, _}], State3} = process_frame([a,b], [b], State2),
  
negative.code: 
  % Test if mail_down_warning is sent again if node was up in between
  mail_down_warning_down_up_down_test() ->
      State0 = init_state(3+?DOWN_GRACE_PERIOD),
      {[], State1} = process_frame([a,b,c], [b], State0),
      State2 = process_frame_no_action(2, [a,b,c], [b], State1),
      {[{mail_down_warning, b}], State3} = process_frame([a,b,c], [b,c], State2),
  