mockito, how to mock call by reference method on same class-CodePudding

Why i can not mock callReffMethod method (call method by refference) on below code ? the problem is real method of callReffMethod always being called.

public class ManageUserService {

public void callReffMethod(List<String> lsStr, boolean flag){
    if (flag){
        lsStr.add("one");
        lsStr.add("two");
    }

}

public void methodA(){
    List<String> lsStr = new ArrayList<>();
    lsStr.add("zero");
    this.callReffMethod(lsStr, true);
    for(String str : lsStr){
        System.out.println(str);
    }
}

}

//Unit Test:

public class ManageUserServiceTest {

@InjectMocks
private ManageUserService manageUserService;

private AutoCloseable closeable;

@BeforeEach
public void init() {
    closeable = MockitoAnnotations.openMocks(this);
}

@AfterEach
void closeService() throws Exception {
    closeable.close();
}

@Test
void methodATest(){
    List<String> lsData = new ArrayList<>();
    lsData.add("start");
    ManageUserService manageUserServiceA = new ManageUserService();
    ManageUserService userSpy = spy(manageUserServiceA);
    doNothing().when(userSpy).callReffMethod(lsData, true);
    userSpy.methodA();
    verify(userSpy).callReffMethod(ArgumentMatchers.any(ArrayList.class), ArgumentMatchers.any(Boolean.class));
}

}

//The result : zero one two

CodePudding user response：

The problem is the difference between the list you're creating in the test method, which is used to match the expected parameters when "doing nothing":

List<String> lsData = new ArrayList<>();
lsData.add("start");
...
doNothing().when(userSpy).callReffMethod(lsData, true);

and the list created in the tested method, passed to the spy object:

List<String> lsStr = new ArrayList<>();
lsStr.add("zero");
this.callReffMethod(lsStr, true);

You're telling Mockito to doNothing if the list is: ["start"], but such list is never passed to the callReffMethod. ["zero"] is passed there, which does not match the expected params, so actual method is called.

Mockito uses equals to compare the actual argument with an expected parameter value - see: the documentation. To work around that ArgumentMatchers can be used.

You can either fix the value added to the list in the test or match the expected parameter in a less strict way (e.g. using anyList() matcher).

CodePudding user response：

ok i did it by using : where manageUserServiceOne is spy of ManageUserService class

 void methodATest(){
        List<String> lsData = new ArrayList<>();
        lsData.add("start");
        doAnswer((invocation) -> {
            System.out.println(invocation.getArgument(0).toString());
            List<String> lsModify = invocation.getArgument(0);
            lsModify.add("mockA");
            lsModify.add("mockB");
            return null;
        }).when(manageUserServiceOne).callReffMethod(anyList(), anyBoolean());
        manageUserServiceOne.methodA();
        verify(manageUserServiceOne).callReffMethod(ArgumentMatchers.any(ArrayList.class), ArgumentMatchers.any(Boolean.class));
    }