Scala test fw

First attempt to use the inhouse Scala testing framework with one test for checking the picture overlay functionality. Keep in mind that I am a beginner Scala dev so code will likely look very "Javaish"
Well the thing is that, in most cases, the existAndDisplayed method is supposed to fail the test and contain error messages for why it is failing. If I change that to return something then everywhere this method is called, which is in many ps, would have to make a check and then fail the test explicitly. That is ugly and something I want to avoid and RuntimeExceptions are se