anchor.diff:  -spec validate_default_bucket(props(), props()) -> {props(), errors()}.
   validate_default_bucket(Existing, New) ->
       {Good, Bad} = validate(New, [], []),
  -    {merge(Good, Existing), Bad}.
  +    validate_post_merge(merge(Good, Existing), Bad).
   
   %% @private properties in new overwrite those in old
   -spec merge(props(), props()) -> props().
  
positive.code:                                      has_w1c(New), valid_w1c(New),
                                       has_consistent(New), valid_consistent(New)])
                     end,
                     collect(with_title("{has_datatype, valid_datatype, allow_mult, has_w1c, valid_w1c, has_consistent, valid_consistent}"),
                             {has_datatype(New), valid_datatype(New), allow_mult(New), has_w1c(New), valid_w1c(New),
                             has_consistent(New), valid_consistent(New)},
                             only_create_if_valid(Result, New)))
              end).
  
  
negative.code: 
  merges_props_test_() ->
      {timeout, ?TEST_TIME_SECS+5, [?_assert(test_merges() =:= true)]}.
  
  -define(LAST_WRITE_WINS, {last_write_wins, true}).
  -define(DVV_ENABLED, {dvv_enabled, true}).
  -define(LWW_DVV, [?LAST_WRITE_WINS, ?DVV_ENABLED]).
  validate_create_bucket_type_test() ->
      {Validated, Errors} = validate_create_bucket_type(?LWW_DVV),
      ?assertEqual([{last_write_wins, true}], Validated),
      ?assertMatch([{dvv_enabled, _Message}], Errors).
  
  validate_update_bucket_type_test() ->
      {Validated, Errors} = validate_update_bucket_type([], ?LWW_DVV),
      ?assertEqual([{last_write_wins, true}], Validated),
      ?assertMatch([{dvv_enabled, _Message}], Errors).
  
  validate_update_typed_bucket_test() ->
      {Validated, Errors} = validate_update_typed_bucket([], ?LWW_DVV),
      ?assertEqual([{last_write_wins, true}], Validated),
      ?assertMatch([{dvv_enabled, _Message}], Errors).
  
  validate_default_bucket_test() ->
      {Validated, Errors} = validate_default_bucket([], ?LWW_DVV),
      ?assertEqual([{last_write_wins, true}], Validated),
      ?assertMatch([{dvv_enabled, _Message}], Errors).
  
  validate_last_write_wins_implies_not_dvv_enabled_test() ->
      {Validated, Errors} = validate_last_write_wins_implies_not_dvv_enabled({?LWW_DVV, []}),
      ?assertEqual([{last_write_wins, true}], Validated),
      ?assertMatch([{dvv_enabled, _Message}], Errors).
  
  test_immutable() ->
     test_immutable(?TEST_TIME_SECS).
  