public void SearchReturnsListOfPatients() { //Arrange repository.Setup(r => r.SearchDoctors(It.IsAny <DoctorSearchModel>())).ReturnsAsync(new List <Doctor>() as IEnumerable <Doctor>); //Act var result = controller.Search(new DoctorSearchModel()).Result; //Assert Assert.IsInstanceOfType(result, typeof(IEnumerable <Doctor>)); }