public void PostCredit_when_has_exception_in_credit_operation() { //Arrange var id = 1; var checkingAccount = new CheckingAccount(); var money = new Money(); _checkingAccountServiceMock.FindById(id).Returns(checkingAccount); _checkingAccountServiceMock .When(c => c.Credit(checkingAccount, money.Value)) .Do(x => { throw new Exception(); }); //Act var result = _checkingAccountController.PostCredit(id, money); //Assert Assert.IsType <BadRequestObjectResult>(result); }