public void When_He_Is_A_Very_Important_Client_Then_Return_True() { // Arrange var customerInfo = new Customer() { Firstname = "Thanh", Surname = "Doan", EmailAddress = "*****@*****.**", DateOfBirth = _dateOfBirth, CompanyId = 1 }; var mockCompany = new Company() { Id = 1, Classification = Classification.Gold, Name = "VeryImportantClient" }; _companyRepository.Stub(x => x.GetById(Arg <int> .Is.Anything)).Return(mockCompany); _clientHelpers.Stub(x => x.IsVipClient(Arg <Company> .Is.Equal(mockCompany))).Return(true); _customerDataAccess.Expect(x => x.AddCustomer(Arg <Customer> .Is.Anything)); // Act var result = _mockCustomerService.AddCustomer(customerInfo); // Assert Assert.AreEqual(true, result); }