anchor.diff:                    join(["foo"], ",")),
       ?assertEqual("foobarbaz",
                     join(["foo", "bar", "baz"], "")),
  +    ?assertEqual("foo" ++ [<<>>] ++ "bar" ++ [<<>>] ++ "baz",
  +                 join(["foo", "bar", "baz"], <<>>)),
  +    ?assertEqual("foobar" ++ [<<"baz">>],
  +                 join(["foo", "bar", <<"baz">>], "")),
  +    ?assertEqual("",
  +                 join([], "any")),
       ok.
   
   quote_plus_test() ->
  
positive.code:             cmd_loop(Port, [Data | Acc])
      end.
  
  %% @spec join([string()], Separator) -> string()
  %% @doc Deprecated, use string:join/2.
  join(Strings, Separator) when is_integer(Separator) ->
      lists:flatten(string:join(Strings, [Separator]));
  join(Strings, Separator) when is_list(Separator) ->
      lists:flatten(string:join(Strings, Separator)).
  
  %% @spec quote_plus(atom() | integer() | float() | string() | binary()) -> string()
  %% @doc URL safe encoding of the given term.
  
negative.code: 
  cmd_port_test_spool(Port, Acc) ->
      receive
          {Port, eof} ->
              Acc;
          {Port, {data, {eol, Data}}} ->
              cmd_port_test_spool(Port, ["\n", Data | Acc]);
          {Port, Unknown} ->
              throw({unknown, Unknown})
  