SpringBoot 테스트 : OutputCaptureRule - 출력되는 Log까지 테스트가 가능하다.

@Slf4j
@RestController
public class GoodGidController {

    @GetMapping("/")
    public String goodGid(){
        log.info("Slf4j");
        System.out.println("System Out");
        return "Heelo goodGid";
    }
}

@RunWith(SpringRunner.class)
@WebMvcTest(GoodGidController.class)
public class GoodGidControllerTest_OutputCaptureRule {

    @Rule
    public OutputCaptureRule outputCaptureRule = new OutputCaptureRule();

    @Autowired
    MockMvc mockMvc;

    @Test
    public void goodGid() throws Exception {
  
        mockMvc.perform(get("/"))
               .andExpect(status().isOk())
               .andExpect(content().string("Hello goodGid"));

        assertThat(outputCaptureRule.toString().contains("Slf4j"));
        assertThat(outputCaptureRule.toString().contains("System Out"));
    }
}