public void ItShouldThrowExceptionWhenCreatingAnExistingPlan()
        {
            var dataService = new Mock <IForecastDataAccessService>();

            dataService.Setup(x => x.PlanExist("Plan")).Returns(true);

            var service = new ForecastService <decimal>(dataService.Object);

            Assert.Throws(typeof(ForecastServiceException), () => service.CreatePlan("Plan", "Plan", 1, "userName", 1, 12));
        }