This repository is intended to help explain some of the caveats you will run into when attempting to use Mockito in a Scala project. It also contains a few helpful patterns for more extended uses of Mockito.
The examples are all written as tests: ScalaMockitoSpec
The examples cover the following scenarios
- Implicits and how they interact with matchers
- Custom matchers and utilizing
matchexpressions - Stubbing methods with a function that depends on matched values
This repository uses a macro to test that a specific line of Scala will not typecheck. The implementation was copied from Slick.
Unfortunately, Scala will not allow you to compile a macro and a file that uses it, in the same pass.
To solve this, I could convert this into a multi-project SBT build, but I feel like that
is overkill. As a hack, If you want to try and run these tests locally, you'll have to comment out
the test that uses ShouldNotTypecheck. It turns out that once your macro has compiled, you can then
use it in the rest of your code (so you could uncomment afterwards to see it in action).
A common caveat you will run into when using Mockito with Scala is that when you stub a method, if you pass in matchers for the arguments (versus using exact values), then all of the arguments need to be matchers. This gets hairy when you have a method with implicits, because Scala will automatically plug in an exact value, implicitly, and Mockito will complain because it wants a matcher. See the examples for clarification on how to deal with this.