anchor.diff:      ?assertMatch({Message, SendNode} when SendNode == FirstNode, ReplyFromSecondNode),
       ?assertMatch({Message, SendNode} when SendNode == SecondNode, ReplyFromLastNode).
   
  -terminate_gracefully_when_ring_nodes_receive_a_quit_message_test() ->
  +when_ring_nodes_receive_a_quit_message_then_they_terminate_gracefully_test() ->
       Message = initial_message,
       N = 3,
       Nodes = start(N, Message),
  
positive.code:     Reply = fetch_message(NodePid2),
      ?assertEqual({Message, NodePid}, Reply).
  
  node_send_quit_message_to_recv_node_then_recv_node_die_test() ->
      NodePid = spawn_node(),
      NodePid2 = spawn_node(),
  
  
negative.code: -include_lib("eunit/include/eunit.hrl").
  -import(ring, [start/2, spawn_node/0, send_message/3, fetch_message/1]).
  
  start_ring_n_nodes_test() ->
      N = 3,
      M = initial_message,
  
  