anchor.diff:  -export([
     basic_op/1,
     update_doc/1,
  - async_update/1,
  +  async_update/1,
  +  revision_conflict/1,
     bad_doc/1,
     create_doc/1,
     docs_count/1,
  
positive.code:   {ok, <<"a">>, _RevId2} = barrel_local:delete(<<"testdb">>, <<"a">>, RevId2, []),
    {error, not_found} = barrel_local:get(<<"testdb">>, <<"a">>, []),
    {ok, <<"a">>, _RevId3} = barrel_local:put(<<"testdb">>, Doc, []).
  
  
  async_update(_Config) ->
  
negative.code:     basic_op,
      update_doc,
      async_update,
      revision_conflict,
      bad_doc,
      create_doc,
      docs_count,
  