TicTacAAE folds do not need default bucket

[Bob-The-Marauder]

From https://www.tiot.jp/riak-docs/riak/kv/2.9.10/using/cluster-operations/tictac-aae-fold/object-stats/ the example for object stats of:

riak_client:aae_fold({
    object_stats,
    {<<"animals">>,<<"dogs">>},
    {<<"A">>,<<"N">>},
    {date,1640995200,1643673600}
    }, Client).

shows that we need both the bucket type of animals and the bucket name of dogs. However, when I tried this for an example where only the default bucket type had been used, it failed. By removing the bucket type though, it worked:

(riak@192.168.56.102)7> riak_client:aae_fold({object_stats, {<<"default">>,<<"car">>}, all, all}, Client).
{ok,[{total_count,0},
     {total_size,0},
     {sizes,[]},
     {siblings,[]}]}
(riak@192.168.56.102)8> riak_client:aae_fold({object_stats, <<"car">>, all, all}, Client).
{ok,[{total_count,1},
     {total_size,535},
     {sizes,[{2,1}]},
     {siblings,[{1,1}]}]}

Although I understand being able to omit the default bucket type would allow buckets of the default type to work with this, I am confused as to why it does not work when the default bucket type is specified as default.

For refrence:

curl http://192.168.56.101:8098/types/default/buckets/car/keys/viper
vroom
curl http://192.168.56.101:8098/buckets/car/keys/viper
vroom