anchor.diff:         N == send_short_avp_length;
          N == send_zero_avp_length;
          N == send_invalid_avp_length;
  -       N == send_invalid_reject ->
  +       N == send_invalid_reject;
  +       N == send_unknown_short_mandatory ->
       Rec;
   answer(Rec, [], _) ->
       Rec.
  
positive.code:          send_protocol_error/1,
           send_arbitrary/1,
           send_unknown/1,
           send_unknown_mandatory/1,
           send_noreply/1,
           send_unsupported/1,
           send_unsupported_app/1,
  
negative.code:                    is_mandatory = true,
                     data = <<17>>}]
          = As.
  
  %% Ditto, and point the AVP length past the end of the message. Expect
  %% 5014 instead of 5001.
  send_unknown_short_mandatory(Config) ->
      send_unknown_short(Config, true, ?INVALID_AVP_LENGTH).
  
  %% Send an STR that the server ignores.
  send_noreply(Config) ->
  