anchor.diff:  interesting_ns_config_event(_) ->
       false.
   
  -interesting_mc_couch_event({set_vbucket, _, _, _}) ->
  +interesting_mc_couch_event({set_vbucket, _, _, _, _}) ->
       true;
   interesting_mc_couch_event({flush_all, _}) ->
       true;
  
positive.code: 
      {noreply, NewState};
  
  handle_info({set_vbucket, Bucket, VBucket, _VBucketState},
              #state{bucket=Bucket, bucket_config=BucketConfig, map=Map,
                     vbucket_states=OldStates} = State) ->
      VBucketState = get_vbucket_state(Bucket, VBucket),
  
negative.code: 
  do_get_vbucket_state(Bucket, VBucket) ->
      try
          {JsonState} = ?JSON_DECODE(mc_couch_vbucket:get_state(VBucket, Bucket)),
          State = proplists:get_value(<<"state">>, JsonState),
          erlang:binary_to_atom(State, latin1)
      catch
          throw:{open_db_error, _, _, {not_found, no_db_file}} ->
  