anchor.diff:  quit_per_testcase(_Function) -> ok.
   
   -spec init_per_round(atom(), [binary()]) -> ok.
  -init_per_round(append, Keys) ->
  +init_per_round(Fun, Keys) when Fun =:= append;
  +                               Fun =:= get ->
     [{ok, Deleted} | OkKeys] =
       edis_db:run(
         edis_db:process(0),
  
positive.code: -export([all/0,
           init/0, init_per_testcase/1, init_per_round/2,
           quit/0, quit_per_testcase/1, quit_per_round/2]).
  -export([append/1, decr/1, decrby/1]).
  
  %% ====================================================================
  %% External functions
  
negative.code:     #edis_command{cmd = <<"APPEND">>, args = [<<"test-string">>, Key],
                    group = strings, result_type = number}).
  
  -spec decr([binary()]) -> integer().
  decr(_) ->
    edis_db:run(
      edis_db:process(0),
      #edis_command{cmd = <<"DECR">>, args = [<<"test-string">>],
                    group = strings, result_type = number}).
  
  -spec decrby([binary()]) -> integer().
  decrby(Keys) ->
    edis_db:run(
      edis_db:process(0),
      #edis_command{cmd = <<"DECRBY">>, args = [<<"test-string">>, length(Keys)],
                    group = strings, result_type = number}).
  
  -spec get([binary()]) -> binary().
  get(_) ->
    edis_db:run(
      edis_db:process(0),
      #edis_command{cmd = <<"GET">>, args = [<<"test-string">>],
                    group = strings, result_type = bulk}).
  