使用@WebMvcTest 和 Mockito BDDMockito 测试 SpringBoot RestController

Question

I am quite new to testing and recently i encounter something weird, or maybe not weird, for the initiated.

SpringBoot version: 2.2.4.RELEASE
Mockito core: 3.1.0

Use Case: RestController test using @WebMvcTest slice, MockBean, MockMvc & BDDMockito:

@WebMvcTest(Controller.class)
@AutoConfigureMockMvc(addFilters = false)
public class ControllerTest {

    @Autowired
    private MockMvc mockMvc;

    @MockBean
    private Service service;

    @Test
    @DisplayName("Some meaningful name")
    public void getXXXShouldBeSuccessful() throws Exception {
        ...
        //NOTE: I know creating objectDto here is useless, but i would like to understand 
        //why it doesn't work when it is passed in the method
        //ObjectDto objectDto = new ObjectDto();
        //objectDto.someSetter(id);
        ...
        given(service.methodName((ObjectDto) any(Object.class))).willReturn(true);   // This works
        //given(service.methodName(objectDto)).willReturn(true);                     //This doesn't work

        this.mockMvc.perform(post(some endpoint)...

And my controller:

    @PostMapping(value = "/{id}")
    public ResponseEntity<JsonResponse> someMethod(
            @PathVariable String id,
            @Valid @RequestBody ObjectDto objectDto) {

        objectDto.someSetter(id);

        if(service.methodName(objectDto)) // <============ Returns false
        //Expected true, but if(service.methodName(objectDto)) is false when testing, 
        //although both objectDto(in my test, and here in the 
        //controller, has the same exact property values)

I found the solution by using (ObjectDto) any(Object.class) , but it would be great to understand why //given(service.methodName(objectDto)).willReturn(true); doesn't work.

Is it because since i am mocking the service method, Mockito doesn't care about what object is being passed in the method?

NOTE 1: objectDTO is just a POJO.
NOTE 2: if objectDTO is replaced by a Map , it works!!!

Answer 1

Try this:

when(service.methodName(any(ObjectDto.class)).thenReturn(true);