How to mock an array containing objects using mockito?

Question

In my Mockito unit test I am trying to mock an array containing instances of the object Message. To do this I try to mock it like normal objects so like:

private var messagesMock = mock(Array<Message>::class.java)

This gives the following error/exception:

org.mockito.exceptions.base.MockitoException: 
Cannot mock/spy class [Lrobot.fsrt.robotguest.common.data.Message;
Mockito cannot mock/spy because :
 - VM does not not support modification of given type

How to mock an array the right way using Mockito?

Answer 1

A distinct non-answer: you (almost) never mock objects that represent containers!

An array is just that: a container.

You create the container with the size you need, and then you put your mocked objects into that ordinary container, and make sure that container with your prepared content gets used by your production code.

It is as simple as that: you don't mock arrays, or lists, or maps: you create them as is, and manipulate their content!