Mocking for a Controller Unit-tests with ScalaTest + Play - scala

Question

I try to write a unit test for a small function in a controller using Play/ScalaTest+ Play. The function I want to test looks like this:
def functionToTest(id: String) = Action.async {
implicit request =>
lang
deeperFunction{ implicit context =>
...
}
}
The deeperFunction
def deeperFunction(block: Context => Future[Result])(implicit request: RequestHeader): Future[Result] = {
// returns Future.successful(Found("DummyUrltoRedirect"))
}
}
The deeperFunction is inherited from a trait and I don't want use the real one here because it's a unit test and so I want to use a matcher instead
val deeperMock = mock[Rainmaker]
val contextMock = mock[Context]
val controller = new Controller()(.....) // list of implicit arguments
"Controller" must {
"return something" in {
val request = FakeRequest("GET", "/something")
when(deeperMock.deeperFunction(anyObject)(anyObject)) thenReturn Future.successful(Found("DummyUrlToRedirect"))
val id = "id"
val result = controller.functionToTest(id).apply(request)
status(result) mustBe Ok
}
}
But when I run this, the line "val result = controller.functionToTest(id).apply(request)" still seems to call the real deeperFunction, not the fake one and therefore throws a null matcher at some point.
I also tried to use
when(controller.deeperFunction(anyObject)(anyObject)) thenReturn Future.successful(Found("DummyUrlToRedirect"))
instead, because the deeperFunction is inherited, but with the same result.
I tried to stick to theses instructions
ScalaTest+Play
dzone
but it seems I am still missing some basics/understanding. Thanks in advance.