anchor.diff:      float_to_binary(Val);
   binary_from_term(Val) when is_atom(Val) ->
       atom_to_binary(Val, utf8).
  +
  +
  +combinations([]) ->
  +    [[]];
  +combinations([Item]) ->
  +    [[Item], []];
  +combinations([Item | Items]) ->
  +    ItemsCombinations = combinations(Items),
  +    ItemsCombinations ++ lists:map(fun(Comb) ->
  +        lists:sort([Item | Comb])
  +    end, ItemsCombinations).
  
positive.code:     ErrorForbidden = rest_test_utils:get_rest_error(?ERROR_FORBIDDEN),
  
      try
          initializer:testmaster_mock_space_user_privileges([Worker], SpaceId, User, SpacePrivs),
          {ok, Code1, _, Resp1} = rest_test_utils:request(Worker, URL, delete, Headers, []),
          ?assertMatch(ErrorForbidden, {Code1, json_utils:decode(Resp1)}),
  
          initializer:testmaster_mock_space_user_privileges([Worker], SpaceId, User, SpacePrivs ++ RequiredPrivs),
          case rest_test_utils:request(Worker, URL, delete, Headers, []) of
  
negative.code:                 RequiredPrivs = case TransferType of
                      replication -> [?SPACE_CANCEL_REPLICATION];
                      eviction -> [?SPACE_CANCEL_EVICTION];
                      migration -> lists:sort([?SPACE_CANCEL_REPLICATION, ?SPACE_CANCEL_EVICTION])
                  end,
                  SpacePrivs = AllSpacePrivs -- RequiredPrivs,
                  ErrorForbidden = rest_test_utils:get_rest_error(?ERROR_FORBIDDEN),
  
                  lists:foreach(fun
                      (PrivsToAdd) when PrivsToAdd =:= RequiredPrivs ->
                          % success will be checked later
                          ok;
                      (PrivsToAdd) ->
                          initializer:testmaster_mock_space_user_privileges([Worker], SpaceId, CancelingUser, SpacePrivs ++ PrivsToAdd),
                          {ok, Code, _, Resp} = rest_test_utils:request(Worker, HTTPPath, delete, Headers, []),
                          ?assertMatch(ErrorForbidden, {Code, json_utils:decode(Resp)})
                  end, combinations(RequiredPrivs)),
  
                  initializer:testmaster_mock_space_user_privileges([Worker], SpaceId, CancelingUser, SpacePrivs ++ RequiredPrivs),
                  ?assertMatch(
  