anchor.diff:      case proplists:get_value(bucket, Opts) of
           undefined ->
               fold_all(fold_objects, FoldObjectsFun, Acc, Opts, State,
  -                    fun default_backend_filter/4);
  +                    fun default_backend_filter/5);
           Bucket ->
               fold_in_bucket(Bucket, fold_objects, FoldObjectsFun, Acc, Opts, State)
       end.
  
positive.code:               }
        end,
        fun(_) ->
                {"start error with invalid backend test",
                 fun() ->
                         %% Attempt to start the backend with a
  
negative.code: -define(CAPABILITIES, [async_fold, index_reformat]).
  -define(ANY_CAPABILITIES, [indexes, iterator_refresh]).
  
  -record (state, {backends :: [{atom(), atom(), term()}], % [{BackendName, BackendModule, SubState}]
                   default_backend :: atom()}).
  
  -type state() :: #state{}.
  