@RequiredArgsConstructor
@Service
public class UserServiceImpl implements UserService {

    private final UserMapper userMapper;

    @Transactional
    @Override
    public Long insertUser(UserSaveRequestDto userSaveRequestDto) {
        Long user_id = userMapper.insertUser(userSaveRequestDto);

        return user_id;
    }

}

我正在测试服务层。
我想知道哪一个应该进一步核实。
下面的代码只是验证是否调用了usermapper的insertuser，或者是否正确地包含了参数，应该进行什么额外的验证？

@ExtendWith(MockitoExtension.class)
public class UserServiceTest {

    @Mock
    UserMapper userMapper;

    @InjectMocks
    UserServiceImpl userService;

    UserSaveRequestDto userSaveRequestDto;

    UserResponseDto userResponseDto;

    @BeforeEach
    void setUp() {
        userSaveRequestDto = UserSaveRequestDto.builder()
            .userName("test")
            .userPhoneNumber("01026137832")
            .build();

        userResponseDto = UserResponseDto.builder()
            .userId(1L)
            .userName("test")
            .userPhoneNumber("01026137832")
            .build();
    }

    // Mockito 이용한 테스트 코드
    @DisplayName("Mock을 사용한 insertUser 테스트")
    @Test
    public void insertUser() {
        // given

        // when
        Long userId = userService.insertUser(userSaveRequestDto);

        // then
        ArgumentCaptor<UserSaveRequestDto> captor = ArgumentCaptor.forClass(UserSaveRequestDto.class);

        then(userMapper).should().insertUser(captor.capture());
        assertThat(captor.getValue()).isEqualTo(userSaveRequestDto);
    }

}