public void AccountService_Register_CanRegister_Success() { // Arrange IMember existedMember = null; UserToRegister user = GetUserToRegister(); _memberService.GetByEmail(user.Email).Returns(existedMember); // Act Result registrationResult = _accountService.Register(user); // Assert Assert.IsNotNull(registrationResult, Common.ShowResponseTypeMismatchMessage(typeof(Result))); Assert.IsTrue(registrationResult.IsSuccess, Common.ShowNotSatisfiedExpectationMessage(true, "registrationResult.IsSuccess")); _userRegistration.Received(1).Register(Arg.Is(RegistrationPredicate(user))); }