public void GetCourseList_WhenCalledWithValidArguments_ReturnsANonEmptyArray() { IPrepareCoursesForInput prepareCoursesForInput = Substitute.For <IPrepareCoursesForInput>(); prepareCoursesForInput.When(p => p.GetCourseList()).Do(context => { throw new Exception("fake exception"); }); Assert.Throws <Exception>(() => prepareCoursesForInput.GetCourseList()); }