Hi Ben,
Loving the course so far, however in section 8 lecture 212, I’d have to disagree with your refactor step of the first test. Adding guards around the pins input parameter being between 0 and 10 is additional logic to the class and show have it’s own tests which check that passing invalid parameters into the method should throw an exception. At this point in the video we are breaking the rules of TDD as we should have written these tests before adding the guard clause. Just my 2 cents anyways.