    @Test
    public void userDTOsToUsersMapWithNullAuthoritiesStringShouldReturnUserWithEmptyAuthorities() {

        userDto.setAuthorities(null);

        List<UserDTO> usersDto = new ArrayList<>();
        usersDto.add(userDto);

        List<User> users = userMapper.userDTOsToUsers(usersDto);

        assertThat(users).isNotEmpty();
        assertThat(users).size().isEqualTo(1);
        assertThat(users.get(0).getAuthorities()).isNotNull();
        assertThat(users.get(0).getAuthorities()).isEmpty();
    }