单元测试踩坑记录: 使用Mockito.when() 时mock总是不生效

@TestConfiguration
@Order
public class TestConfiguration {
    public TestConfiguration() {
    }

    @Bean
    @ConditionalOnMissingBean({ObjectMapper.class})
    ObjectMapper testObjectMapper() {
        return (new WebConfiguration()).objectMapper();
    }

    @Bean
    @ConditionalOnMissingBean({ConcurrentJobExecutor.class})
    ConcurrentJobExecutor testConCurrentExecutor() {
        return new ConcurrentTestExecutor();
    }

    @Bean
    @ConditionalOnMissingBean({SpringBeanUtil.class})
    SpringBeanUtil testSpringBeanUtil() {
        return new SpringBeanUtil();
    }

    @Bean
    @ConditionalOnMissingBean({ConversionService.class})
    public ConversionService conversionService() {
        return ApplicationConversionService.getSharedInstance();
    }
}

@ContextConfiguration(
    initializers = {ConfigFileApplicationContextInitializer.class},
    classes = {TestConfiguration.class}
)
@ExtendWith({SpringExtension.class})
@TestInstance(Lifecycle.PER_CLASS)
public class SpringTestExtension {
    @Autowired
    ApplicationContext ctx;

    public SpringTestExtension() {
    }

    @BeforeAll
    public void beforeAllTest() {
        SpringBeanUtil.setContext(this.ctx);
    }
}

@Component
public class CommonService {

    public List<String> a(Integer boo, List<String> strings) {
        xxxx
    }
}

@Component
public class ExecuteService {

    @Autowired
    private CommonService commonService;

    public void b() {
        commonService.a();
        xxx
    }
}


@Import({ExecuteService.class})
class Test extends SpringTestExtension{
   @Autowired
   private ExecuteService executeService;

   @MockBean
   private CommonService commonService;

   @Test
   public void test() {
      Mockito.when(commonService.a(any(), anyList())).thenReturn(Lists.newArrayList("test"));
   }
}

(1)问题
when(commonService.a(any(), anyList())).thenReturn(Lists.newArrayList("test"))
这一行代码mock一直不生效，实际调用commonService.a()时总是返回emptyList。

(2)原因
目前Mockito.when()方法只对any()生效 ，anyList(), anyMap()作为参数时，均会返回默认结果值：emptyList, "", null等。(⚠️但是jetbrains idea默认提示时对于List<T>, Map<K, V>这种参数都是提示anyList, anyMap, 这里需要特别注意)

(3)修改：
修改为 when(commonService.a(any(), any())).thenReturn(Lists.newArrayList("test")) 后， 返回结果正常： Lists.newArrayList("test")