public async Task GetTopVolunteerData_WhenDataExist_ShouldReturnTopEnrollments() { //Arrange var dict = new Dictionary <string, List <decimal> >(); dict.Add("key1", new List <decimal> { 1, 2 }); _enrollmentProcessorMock.Setup(p => p.GetTopVolunteerData(null)).ReturnsAsync(dict); var controller = new EnrollmentController(_enrollmentProcessorMock.Object); //Act var response = await controller.GetTopVolunteerData(); //Assert var okResult = Assert.IsType <OkObjectResult>(response); var returnValue = Assert.IsType <Dictionary <string, List <decimal> > >(okResult.Value); Assert.NotEmpty(returnValue); }