Spring Boot TDD 工作流

针对具有 80% 以上覆盖率（单元测试 + 集成测试）的 Spring Boot 服务的 TDD 指南。

适用场景

• 新功能或 API 端点开发
• Bug 修复或重构
• 添加数据访问逻辑或安全规则

工作流

1. 先写测试（测试应当失败）
2. 实现通过测试的最简代码
3. 在测试通过的情况下重构代码
4. 强制执行覆盖率检查 (JaCoCo)

单元测试 (JUnit 5 + Mockito)

@ExtendWith(MockitoExtension.class)
class MarketServiceTest {
  @Mock MarketRepository repo;
  @InjectMocks MarketService service;

  @Test
  void createsMarket() {
    CreateMarketRequest req = new CreateMarketRequest("name", "desc", Instant.now(), List.of("cat"));
    when(repo.save(any())).thenAnswer(inv -> inv.getArgument(0));

    Market result = service.create(req);

    assertThat(result.name()).isEqualTo("name");
    verify(repo).save(any());
  }
}

模式：

• 准备-执行-断言 (Arrange-Act-Assert)
• 避免部分 Mock；优先使用显式打桩 (Stubbing)
• 使用 @ParameterizedTest 处理用例变体

Web 层测试 (MockMvc)

@WebMvcTest(MarketController.class)
class MarketControllerTest {
  @Autowired MockMvc mockMvc;
  @MockBean MarketService marketService;

  @Test
  void returnsMarkets() throws Exception {
    when(marketService.list(any())).thenReturn(Page.empty());

    mockMvc.perform(get("/api/markets"))
        .andExpect(status().isOk())
        .andExpect(jsonPath("$.content").isArray());
  }
}

集成测试 (SpringBootTest)

@SpringBootTest
@AutoConfigureMockMvc
@ActiveProfiles("test")
class MarketIntegrationTest {
  @Autowired MockMvc mockMvc;

  @Test
  void createsMarket() throws Exception {
    mockMvc.perform(post("/api/markets")
        .contentType(MediaType.APPLICATION_JSON)
        .content("""
          {"name":"Test","description":"Desc","endDate":"2030-01-01T00:00:00Z","categories":["general"]}
        """))
      .andExpect(status().isCreated());
  }
}

持久层测试 (DataJpaTest)

@DataJpaTest
@AutoConfigureTestDatabase(replace = AutoConfigureTestDatabase.Replace.NONE)
@Import(TestContainersConfig.class)
class MarketRepositoryTest {
  @Autowired MarketRepository repo;

  @Test
  void savesAndFinds() {
    MarketEntity entity = new MarketEntity();
    entity.setName("Test");
    repo.save(entity);

    Optional<MarketEntity> found = repo.findByName("Test");
    assertThat(found).isPresent();
  }
}

Testcontainers

• 使用可重用的 Postgres/Redis 容器来镜像生产环境
• 通过 @DynamicPropertySource 将 JDBC URL 注入到 Spring 上下文中

测试覆盖率 (JaCoCo)

Maven 配置片段：

<plugin>
  <groupId>org.jacoco</groupId>
  <artifactId>jacoco-maven-plugin</artifactId>
  <version>0.8.14</version>
  <executions>
    <execution>
      <goals><goal>prepare-agent</goal></goals>
    </execution>
    <execution>
      <id>report</id>
      <phase>verify</phase>
      <goals><goal>report</goal></goals>
    </execution>
  </executions>
</plugin>

断言 (Assertions)

• 为了提高可读性，优先使用 AssertJ (assertThat)
• 对于 JSON 响应，使用 jsonPath
• 对于异常：assertThatThrownBy(...)

测试数据生成器 (Test Data Builders)

class MarketBuilder {
  private String name = "Test";
  MarketBuilder withName(String name) { this.name = name; return this; }
  Market build() { return new Market(null, name, MarketStatus.ACTIVE); }
}

CI 命令

• Maven: mvn -T 4 test 或 mvn verify
• Gradle: ./gradlew test jacocoTestReport

记住：保持测试快速、隔离且具有确定性。测试行为，而不是实现细节。