How to use InOrderContextImpl method of org.mockito.internal.invocation.InvocationsFinderTest class

Just use Mockito.matches(String), for example:

Mockito.verify(mockMyObject).
  myMethod(
    Mockito.matches("(.*apple.*banana.*)|(.*banana.*apple.*)"
  )
);

Perhaps I'm missing something, but why not just do this:

Map.Entry<Integer, Action> entrySet = <whatever you want it to return>
Map mockAvailableActions = mock(Map.class);
when(mockAvailableActions.entrySet()).thenReturn(entrySet);

Also consider whether you actually need a mock Map at all, wouldn't a real one do the job? Mocks are usually used to replace other pieces of your code which you don't want to be involved in your unit test, a Map is part of the core Java language and isn't usually mocked out.

To directly answer your question, yes, you can mock some methods without mocking others. This is called a partial mock. See the Mockito documentation on partial mocks for more information.

For your example, you can do something like the following, in your test:

Stock stock = mock(Stock.class);
when(stock.getPrice()).thenReturn(100.00);    // Mock implementation
when(stock.getQuantity()).thenReturn(200);    // Mock implementation
when(stock.getValue()).thenCallRealMethod();  // Real implementation

In that case, each method implementation is mocked, unless specify thenCallRealMethod() in the when(..) clause.

There is also a possibility the other way around with spy instead of mock:

Stock stock = spy(Stock.class);
when(stock.getPrice()).thenReturn(100.00);    // Mock implementation
when(stock.getQuantity()).thenReturn(200);    // Mock implementation
// All other method call will use the real implementations

In that case, all method implementation are the real one, except if you have defined a mocked behaviour with when(..).

There is one important pitfall when you use when(Object) with spy like in the previous example. The real method will be called (because stock.getPrice() is evaluated before when(..) at runtime). This can be a problem if your method contains logic that should not be called. You can write the previous example like this:

Stock stock = spy(Stock.class);
doReturn(100.00).when(stock).getPrice();    // Mock implementation
doReturn(200).when(stock).getQuantity();    // Mock implementation
// All other method call will use the real implementations

---

Another possibility may be to use org.mockito.Mockito.CALLS_REAL_METHODS, such as:

Stock MOCK_STOCK = Mockito.mock( Stock.class, CALLS_REAL_METHODS );

This delegates unstubbed calls to real implementations.

---

However, with your example, I believe it will still fail, since the implementation of getValue() relies on quantity and price, rather than getQuantity() and getPrice(), which is what you've mocked.

Another possibility is to avoid mocks altogether:

@Test
public void getValueTest() {
    Stock stock = new Stock(100.00, 200);
    double value = stock.getValue();
    assertEquals("Stock value not correct", 100.00*200, value, .00001);
}

You're nesting mocking inside of mocking. You're calling getSomeList(), which does some mocking, before you've finished the mocking for MyMainModel. Mockito doesn't like it when you do this.

Replace

@Test
public myTest(){
    MyMainModel mainModel =  Mockito.mock(MyMainModel.class);
    Mockito.when(mainModel.getList()).thenReturn(getSomeList()); --> Line 355
}

with

@Test
public myTest(){
    MyMainModel mainModel =  Mockito.mock(MyMainModel.class);
    List<SomeModel> someModelList = getSomeList();
    Mockito.when(mainModel.getList()).thenReturn(someModelList);
}

To understand why this causes a problem, you need to know a little about how Mockito works, and also be aware in what order expressions and statements are evaluated in Java.

Mockito can't read your source code, so in order to figure out what you are asking it to do, it relies a lot on static state. When you call a method on a mock object, Mockito records the details of the call in an internal list of invocations. The when method reads the last of these invocations off the list and records this invocation in the OngoingStubbing object it returns.

The line

Mockito.when(mainModel.getList()).thenReturn(someModelList);

causes the following interactions with Mockito:

• Mock method mainModel.getList() is called,
• Static method when is called,
• Method thenReturn is called on the OngoingStubbing object returned by the when method.

The thenReturn method can then instruct the mock it received via the OngoingStubbing method to handle any suitable call to the getList method to return someModelList.

In fact, as Mockito can't see your code, you can also write your mocking as follows:

mainModel.getList();
Mockito.when((List<SomeModel>)null).thenReturn(someModelList);

This style is somewhat less clear to read, especially since in this case the null has to be casted, but it generates the same sequence of interactions with Mockito and will achieve the same result as the line above.

However, the line

Mockito.when(mainModel.getList()).thenReturn(getSomeList());

causes the following interactions with Mockito:

1. Mock method mainModel.getList() is called,
2. Static method when is called,
3. A new mock of SomeModel is created (inside getSomeList()),
4. Mock method model.getName() is called,

At this point Mockito gets confused. It thought you were mocking mainModel.getList(), but now you're telling it you want to mock the model.getName() method. To Mockito, it looks like you're doing the following:

when(mainModel.getList());
// ...
when(model.getName()).thenReturn(...);

This looks silly to Mockito as it can't be sure what you're doing with mainModel.getList().

Note that we did not get to the thenReturn method call, as the JVM needs to evaluate the parameters to this method before it can call the method. In this case, this means calling the getSomeList() method.

Generally it is a bad design decision to rely on static state, as Mockito does, because it can lead to cases where the Principle of Least Astonishment is violated. However, Mockito's design does make for clear and expressive mocking, even if it leads to astonishment sometimes.

Finally, recent versions of Mockito add an extra line to the error message above. This extra line indicates you may be in the same situation as this question:

3: you are stubbing the behaviour of another mock inside before 'thenReturn' instruction if completed

Check this issue

This seems to happen when a mock is created at instantation time.

If I set up my mocks in an @Before method the issue goes away.

Even more meaningful :

import static org.mockito.Mockito.never;
import static org.mockito.Mockito.verify;

// ...

verify(dependency, never()).someMethod();

The documentation of this feature is there §4 "Verifying exact number of invocations / at least x / never", and the never javadoc is here.

I would strongly suggest that you avoid using System.currentTimeMillis (and new Date() etc) in your general code.

Instead, create a Clock interface representing "a service to give you the current time" and then create one implementation which does use System.currentTimeMillis or whatever, and a fake implementation that you can control explicitly.

Use dependency injection to make an instance of this service available to code which needs it. In production, use the System.currentTimeMillis version, and in testing use your fake.

This gives you the ability not just to stop time, but to set it to whatever you want - so you can have static test data which you know will never expire, and you can easily test tricky things around boundaries etc. I've used this approach very successfully in many projects, to the extent that in my Noda Time project it's the way of getting at "the current time".

Note that if you're doing any serious amount of time work in Java, I'd recommend using Joda Time, and making your Clock interface return an Instant:

public interface Clock {
    Instant now();
}

You could extract a method for doing the actual reading and then test that instead. That would mean you only have to mock a single reader. For example, your code would be something like this:

public void aMethod(){
    File f = map.get("key1")
    BuffereReader r = new BufferedReader(new FileReader(f));
    readStuff(r);
}

public void readStuff(BufferedReader r){
    String line=null;
    do {
        line=r.readLine();
    } while(r!=null);
}

then your test code would be more like the following:

BufferedReader bufferedReader = Mockito.mock(BufferedReader.class);
Mockito.when(bufferedReader.readLine()).thenReturn("line1", "line2", "line3");
objUnderTest.readStuff(bufferedReader);
//verify result

The two syntaxes for stubbing are roughly equivalent. However, you can always use doReturn/when for stubbing; but there are cases where you can't use when/thenReturn. Stubbing void methods is one such. Others include use with Mockito spies, and stubbing the same method more than once.

One thing that when/thenReturn gives you, that doReturn/when doesn't, is type-checking of the value that you're returning, at compile time. However, I believe this is of almost no value - if you've got the type wrong, you'll find out as soon as you run your test.

I strongly recommend only using doReturn/when. There is no point in learning two syntaxes when one will do.

You may wish to refer to my answer at Forming Mockito "grammars" - a more detailed answer to a very closely related question.