public User(String name) {
        this.name = name;
        this.roles = null;
    }
@Test
    void testUser() {
        Set<String> roles = new HashSet<>();
        roles.add("userRole1");
        roles.add("userRole2");
        User user = new User("userName", roles);

        assertThat(user.getName()).isEqualTo("userName");
        assertThat(user.getRoles()).hasSize(2).contains("userRole1", "userRole2");
        assertThat(user.getId()).isNotNegative().isLessThan(100);

        User secondUser = new User("secondUser");
        assertThat(secondUser.getRoles()).isNull();
    }