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javajunitassertmockitoverify

Is there a way of having something like jUnit Assert message argument in Mockito's verify method?


Let's assume a snippet of testing code:

Observable model = Class.forName(fullyQualifiedMethodName).newInstance();
Observer view = Mockito.mock(Observer.class);
model.addObserver(view);
for (Method method : Class.forName(fullyQualifiedMethodName).getDeclaredMethods())
{
  method.invoke(model, composeParams(method));
  model.notifyObservers();
  Mockito.verify(
    view, Mockito.atLeastOnce()
  ).update(Mockito.<Observable>any(), Mockito.<Object>any());
}

Mockito.verify method throws an exception if a method in a model hasn't invoked Observable.setChanged() method.

Problem: without adding loggers/System.print.out I can't realize what's the current method that has failed the test. Is there a way of having something similar to jUnit Assert methods:

Assert.assertEquals(
  String.format("instances %s, %s should be equal", inst1, inst2),
  inst1.getParam(), 
  inst2.getParam()
);

SOLUTION:

verify(observer, new VerificationMode()
{
  @Override
  public void verify(VerificationData data)
  {
    assertTrue(
        format(
            "method %s doesn't call Observable#setChanged() after changing the state of the model",
            method.toString()
        ),
        data.getAllInvocations().size() > 0);
  }
}).update(Mockito.<Observable>any(), Mockito.<Object>any());

Solution

  • This question is ancient, but Mockito v2.1.0+ now has a built-in feature for this.

    verify(mock, description("This will print on failure")).someMethod("some arg");
    

    More examples included from @Lambart's comment below:

    verify(mock, times(10).description("This will print if the method isn't called 10 times")).someMethod("some arg");
    verify(mock, never().description("This will print if someMethod is ever called")).someMethod("some arg");
    verify(mock, atLeastOnce().description("This will print if someMethod is never called with any argument")).someMethod(anyString());