anchor.diff:    {ok, <<"a">>, _RevId2} = barrel_httpc:delete(db(Config), <<"a">>, [{rev, RevId2}]),
     {error, not_found} = barrel_httpc:get(db(Config), <<"a">>, []),
     {ok, <<"a">>, _RevId3} = barrel_httpc:post(db(Config), Doc, []).
  +
  +
  +delete_doc_without_revision(Config) ->
  +  Doc = #{ <<"id">> => <<"a">>, <<"v">> => 1},
  +  {error, not_found} = barrel_httpc:get(db(Config), <<"a">>, []),
  +  {ok, <<"a">>, RevId} = barrel_httpc:post(db(Config), Doc, []),
  +  {ok, Doc, _Meta} = barrel_httpc:get(db(Config), <<"a">>, []),
  +  {ok, _, _} = barrel_httpc:delete(db(Config), <<"a">>, []),
  +  {error, not_found} = barrel_httpc:get(db(Config), <<"a">>, []).
   
   update_with(Config) ->
     Doc = #{ <<"id">> => <<"a">>, <<"v">> => 1},
  
positive.code:   db_ops/1,
    basic_op/1,
    update_doc/1,
    update_with/1,
    async_update/1,
    bad_doc/1,
  
negative.code:     db_ops,
      basic_op,
      update_doc,
      delete_doc_without_revision,
      update_with,
      async_update,
      bad_doc,
  