public void DeactivateAdminUser_does_not_deactivate_admin_user_without_confirmation() { // Given var adminUserId = UserTestHelper.GetDefaultAdminUser().Id; const string expectedErrorMessage = "You must confirm before deactivating this account"; var deactivateViewModel = Builder <DeactivateAdminViewModel> .CreateNew().With(vm => vm.Confirm = false).Build(); administratorController.ModelState.AddModelError(nameof(DeactivateAdminViewModel.Confirm), expectedErrorMessage); // When var result = administratorController.DeactivateAdmin(adminUserId, deactivateViewModel); // Then result.Should().BeViewResult().WithDefaultViewName().ModelAs <DeactivateAdminViewModel>(); administratorController.ModelState[nameof(DeactivateAdminViewModel.Confirm)].Errors[0].ErrorMessage.Should() .BeEquivalentTo(expectedErrorMessage); A.CallTo(() => userDataService.DeactivateAdmin(adminUserId)).MustNotHaveHappened(); }