Hi! I just published this post: https://medium.com/@orogersilva/helping-androiddev-to-mock-tests-in-kotlin-ab3be5204559#.vfyojx4fm

orogersilva: I haven't found it useful to mock classes in Kotlin. Can you show me a reference to some example code how and why do you use this feature?

I just updated the post with a link for an open source project that implements unit tests with the mocks support.

@orogersilva So if you just change both params of

PubRepository::getInstance

to

PubDataSource

type everything will still compile you won't have a need for class mocking support.

@mg6maciej Unit tests requires mocks for classes to be tested in isolation. That is, without the influence of dependencies. This can be done via dependency injection.

I usually have interfaces or function types as dependencies for things I unit test. In your example it's also possible to easily change the code to depend on interfaces instead of classes.

@mg6maciej I agree with you (again). But, depending on context, it is not good practice to introduce interfaces exclusively to make unit testing possible. For the example context it is a good idea. However, there are contexts that do not.

Well, let me know if you have an example that shows this.