anchor.diff:  -include_lib("eunit/include/eunit.hrl").
   
   get_values_test() ->
  -    [?assertEqual(get_values(Keys, List), Expected)
  +    [?assertEqual(Expected, get_values(Keys, List))
        || {Keys, List, Expected}
               <- [{[a], [{a, 1}, {b, 2}], {ok, [1]}},
                   {[b], [{a, 1}, {b, 2}], {ok, [2]}},
  
positive.code:                ]].
  
  to_query_string_test() ->
    [?assertEqual(to_query_string(Props), Expected)
     || {Props, Expected}
        <- [
            { [{a, <<"1234">>}], <<"a=1234&">> },
  
negative.code: -spec oauth_for(provider | email, binary(), [proplists:property()]) ->
      {ok, {ClientID :: string, ClientSecret :: string}} | {error, _}.
  oauth_for(provider, Provider, Providers) ->
      lager:warning("Providers: ~p", [Providers]),
      case proplists:get_value(Provider, Providers) of
        undefined ->
          {error, {no_provider_oauth, Provider}}; 
  