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TDD - Am I doing it correctly?

I have a class that deals with Account stuff. It provides methods to login, reset password and create new accounts so far.
I inject the dependencies through the constructor. I have tests that validates each dependency's reference, if the reference is null it throws an ArgumentNullException.
The Account class exposes each of these dependencies through read only properties, I then have tests that validates if the reference passed on the constructor is the same that the property returns. I do this to make sure the references are being held by the class. (I don't know if this is a good practice too.)
First question: Is this a good practice in TDD? I ask this because this class has 6 dependencies so far, and it gets very repetitive and also the tests get pretty long as I have to mock all the dependencies for each test. What I do is just a copy and paste every time and just change the dependency's reference being tested.
Second question: my account creation method does things like validating the model passed, inserting data in 3 different tables or a forth table if a certain set of values are present and sending an email. What should I test here? I have so far a test that checks if the model validation gets executed, if the Add method of each repository gets called, and in this case, I use the Moq's Callback method of the mocked repository to compare each property being added to the repository against the ones I passed by the model.
Something like:
userRepository
.Setup(r => r.Add(It.IsAny<User>()))
.Callback<User>(u =>
{
Assert.AreEqual(model.Email, u.Email);
Assert.IsNotNull(u.PasswordHash);
//...
})
.Verifiable();
As I said, these tests are getting longer, I think that it doesn't hurt to test anything I can, but I don't know if it's worth it as it it's taking time to write the tests.

The purpose of testing is to find bugs.
Are you really going to have a bug where the property exists but is not initialized to the value from the constructor?
public class NoNotReally {
private IMyDependency1 _myDependency;
public IMyDependency1 MyDependency {get {return _myDependency;}}
public NoNotReally(IMyDependency dependency) {
_myDependency = null; // instead of dependency. Really?
}
}
Also, since you're using TDD, you should write the tests before you write the code, and the code should exist only to make the tests pass. Instead of your unnecessary tests of the properties, write a test that demonstrates that your injected dependency is being used. In order or such a test to pass, the dependency will need to exist, it will need to be of the correct type, and it will need to be used in the particular scenario.
In my example, the dependency will come to exist because it's needed, not because some artificial unit test required it to be there.

You say writing these tests feels repetitive. I say you feel the major benefit of TDD. Which is in fact not writing software with less bugs and not writing better software, because TDD doesn't guarantee either (at least not inherently). TDD forces you to think about design decisions and make design decisions all. The. Time. (And reduce debugging time.) If you feel pain while doing TDD, it's usually because a design decision is coming back to bite you. Then it's time to switch to your refactoring hat and improve the design.
Now in this particular case it's just the design of your tests, but you have to make design decisions for those as well.
As for testing whether properties are set. If I understand you correctly, you exposed those properties just for the sake of testing? In that case I'd advise against that. Assume you have a class with a constructor parameter and have a test that asserts the construtor should throw on null arguments:
public class MyClass
{
public MyClass(MyDependency dependency)
{
if (dependency == null)
{
throw new ArgumentNullException("dependency");
}
}
}
[Test]
public void ConstructorShouldThrowOnNullArgument()
{
Assert.Catch<ArgumentNullException>(() => new MyClass(null));
}
(TestFixture class omitted)
Now when you start to write a test for an actual business method of the class under test, the parts will start to fit together.
[Test]
public void TestSomeBusinessFunctionality()
{
MyDependency mockedDependency;
// setup mock
// mock calls on mockedDependency
MyClass myClass = new MyClass(mockedDependency);
var result = myClass.DoSomethingOrOther();
// assertions on result
// if necessary assertion on calls on mockedDependency
}
At that point, you will have to assign the injected dependency from the constructor to a field so you can use it in the method later. And if you manage to get the test to pass without using the dependency... well, heck, obviously you didn't need it to begin with. Or, maybe, you'll only start to need it for the next test.
About the other point. When it becomes a hassle to test all the reponsibilities of a method or class, TDD is telling you that the method/class is doing to much and would maybe like to be split up into parts that are easy to test. E.g. one class for verification, one for mapping and one for executing the storage calls.
That can very well lead to over-engineering, though! So watch out for that and you'll develop a feeling for when to resist the urge for more indirection. ;)
To test if properties are mapped properly, I'd suggest to use stubs or self-made fake objects which have simple properties. That way you can simply compare the source and target properties and don't have to make lengthy setups like the one you posted.

Normally in unit tests (especially in TDD), you are not going to test every single statement in the class that you are testing. The main purpose of the TDD unit tests is to test the business logic of the class, not the initialization stuff.
In other words, you give scenarios (remember to include edge cases too) as input and check the results, which can either be the final values of the properties and/or the return values of the methods.
The reason you don't want to test every single possible code path in your classes is because should you ever decide to refactor your classes later on, you only need to make minimal changes to your TDD unit tests, as they are supposed to be agnostic to the actual implementation (as much as possible).
Note: There are other types of unit tests, such as code coverage tests, that are meant to test every single code path in your classes. However, I personally find these tests impractical, and certainly not encouraged in TDD.

Unit testing a class that tracks state

I am abstracting the history tracking portion of a class of mine so that it looks like this:
private readonly Stack<MyObject> _pastHistory = new Stack<MyObject>();
internal virtual Boolean IsAnyHistory { get { return _pastHistory.Any(); } }
internal virtual void AddObjectToHistory(MyObject myObject)
{
if (myObject == null) throw new ArgumentNullException("myObject");
_pastHistory.Push(myObject);
}
internal virtual MyObject RemoveLastObject()
{
if(!IsAnyHistory) throw new InvalidOperationException("There is no previous history.");
return _pastHistory.Pop();
}
My problem is that I would like to unit test that Remove will return the last Added object.
AddObjectToHistory
RemoveObjectToHistory -> returns what was put in via AddObjectToHistory
However, it isn't really a unit test if I have to call Add first? But, the only way that I can see to do this in a true unit test way is to pass in the Stack object in the constructor OR mock out IsAnyHistory...but mocking my SUT is odd also. So, my question is, from a dogmatic view is this a unit test? If not, how do I clean it up...is constructor injection my only way? It just seems like a stretch to have to pass in a simple object? Is it ok to push even this simple object out to be injected?

There are two approaches to those scenarios:
Interfere into design, like making _pastHistory internal/protected or injecting stack
Use other (possibly unit tested) methods to perform verification
As always, there is no golden rule, although I'd say you generally should avoid situations where unit tests force design changes (as those changes will most likely introduce ambiguity/unnecessary questions to code consumers).
Nonetheless, in the end it is you who has to weigh how much you want unit test code interfere into design (first case) or bend the perfect unit test definition (second case).
Usually, I find second case much more appealing - it doesn't clutter original class code and you'll most likely have Add already tested - it's safe to rely on it.

I think it's still a unit test, assuming MyObject is a simple object. I often construct input parameters to unit test methods.
I use Michael Feather's unit test criteria:
A test is not a unit test if:
It talks to the database
It communicates across the network
It touches the file system
It can't run at the same time as any of your other unit tests
You have to do special things to your environment (such as editing config files) to run it.
Tests that do these things aren't bad. Often they are worth writing, and they can be written in a unit test harness. However, it is important to be able to separate them from true unit tests so that we can keep a set of tests that we can run fast whenever we make our changes.

My 2 cents... how would the client know if remove worked or not ? How is a 'client' supposed to interact with this object? Are clients going to push in a stack to the history tracker? Treat the test as just another user/consumer/client of the test subject.. using exactly the same interaction as in real production.
I haven't heard of any rule stating that you're not allowed to call multiple methods on the object under test.
To simulate, stack is not empty. I'd just call Add - 99% case. I'd refrain from destroying the encapsulation of that object.. Treat objects like people (I think I read that in Object Thinking). Tell them to do stuff.. don't break-in and enter.
e.g. If you want someone to have some money in their wallet,
the simple way is to give them the money and let them internally put it into their wallet.
throw their wallet away and stuff in a wallet in their pocket.
I like Option1. Also see how it frees you from implementation details (which induce brittleness in tests). Let's say tomorrow the person decides to use an online wallet. The latter approach will break your tests - they will need to be updated for pushing in an online wallet now - even though the object behavior is not broken.
Another example I've seen is for testing Repository.GetX() where people break-in to the DB to inject records with SQL now in the unit test.. where it would have be considerably cleaner and easier to call Repository.AddX(x) first. Isolation is desired but not to the extent that it overrides pragmatism.
I hope I didn't come on too strong here.. it just pains me to see object APIs being 'contorted for testability' to the point where it no longer resembles the 'simplest thing that could work'.

I think you're trying to be a little overly specific with your definition of a unit test. You should be testing the public behavior of your class, not the minute implementation details.
From your code snippet, it looks like all you really need to care about is whether a) calling AddObjectToHistory causes IsAnyHistory to return true and b) RemoveLastObject eventually causes IsAnyHistory to return false.

As stated in the other answers I think your options can be broken down like so.
You take a dogmatic approach to your testing methodology and add constructor injection for the stack object so you can inject your own fake stack object and test your methods.
You write a separate test for add and remove, the remove test will use the add method but consider it a part of the test setup. As long as your add test passes, your remove should be too.

How test code with lots of dependencies

I am working on a large codebase with basically no unit test coverage. We are about to start moving toward a more test-driven approach, so I thought I would try to write a unit test for a very simple function I added, basically
class ClassUnderTest {
public void SetNoMatchingImage() {
currentState.State = FSMState.NoMatchingImage;
... // Some more logic
NotifyViews();
}
public ViewStatus GetStatus() {
...
if (currentState.State == FSMState.NoMatchingImage)
return ViewStatus.EmptyScreen;
...
}
...
}
Ok, so test this, I would just like to do:
[Test]
public void TestSetNoMatchingImage() {
ClassUnderTest view = new ClassUnderTest(...);
view.SetNoMatchingImage();
Assert.AreEqual(ViewStatus.EmptyScreen, view.Status);
}
But my problem here is that the ClassUnderTest constructor takes 3 arguments to non-interfaces that cannot be null, so I cannot easily create a ClassUnderTest. I can try to either create instances of these classes or stub them, but the problem is the same for them: each of the contructors take arguments that has to be created. And the problem is the same for... and so on. The result is of course a very large overhead and a lot of code needed even for very simple tests.
Is there a good way of dealing with cases like this to make the test cases easier to write?

You'll have lots of situations like this when you start refactoring a project without tests if it wasn't design with Dependency Injection in mind and the mocking framework you use cannot mock concrete classes (such as NMock).
As Andriys just mentioned, Typemock (and moq too) can mock concrete classes as long as it got virtual members.
Personally, I would extract an interface from each of those three classes and inject the interfaces as part of some refactoring to make the class easy to test. I can't remember if VS has a refactor to extract an interface in 2 clicks, which wouldn't take too long.

I would recommend looking at Typemock Isolator framework. According to Art of Unit Testing book by Roy Osherove, it's your best bet when writing unit tests for legacy code:
...it’s the only one [framework] that allows you to create stubs and mocks of dependencies in production code without needing to refactor it at all, saving valuable time in bringing a component under test.
Cheers!

I'd second the recommendation for Typemock, and the solutions suggested in the other answers. In addition to what's already being said Michael Feathers has written a book dealing with the patterns that you're bumping up against called 'Working Effectively With Legacy Code' -
http://www.amazon.com/Working-Effectively-Legacy-Michael-Feathers/dp/0131177052/ref=sr_1_1?ie=UTF8&qid=1313835584&sr=8-1
There's a PDF extract here - http://www.objectmentor.com/resources/articles/WorkingEffectivelyWithLegacyCode.pdf

Need ideas for a TDD Approach

We have just released a re-written(for the 3rd time) module for our proprietary system. This module, which we call the Load Manager, is by far the most complicated of all the modules in our system to date. We are trying to get a comprehensive test suite because every time we make any kind of significant change to this module there is hell to pay for weeks in sorting out bugs and quirks. However, developing a test suite has proven to be quite difficult so we are looking for ideas.
The Load Manager's guts reside in a class called LoadManagerHandler, this is essentially all of the logic behind the module. This handler calls upon multiple controllers to do the CRUD methods in the database. These controllers are essentially the top layer of the DAL that sits on top and abstracts away our LLBLGen generated code.
So it is easy enough to mock these controllers, which we are doing using the Moq framework. However the problem comes in the complexity of the Load Manager and the issues that we receive aren't in dealing with the simple cases but the cases where there is a substantial amount of data contained within the handler.
To briefly explain the load manager contains a number of "unloaded" details, sometimes in the hundreds, that are then dropped into user created loads and reship pools. During the process of creating and populating these loads there is a multitude of deletes, changes, and additions that eventually cause issues to appear. However, because when you mock a method of an object the last mock wins, ie:
jobDetailControllerMock.Setup(mock => mock.GetById(1)).Returns(jobDetail1);
jobDetailControllerMock.Setup(mock => mock.GetById(2)).Returns(jobDetail2);
jobDetailControllerMock.Setup(mock => mock.GetById(3)).Returns(jobDetail3);
No matter what I send to jobDetailController.GetById(x) I will always get back jobDetail3. This makes testing almost impossible because we have to make sure that when changes are made all points are affected that should be affected.
So, I resolved to using the test database and just allowing the reads and writes to occur as normal. However, because you can't(read: should not) dictate the order of your tests, tests that are run earlier could cause tests that run later to fail.
TL/DR: I am essentially looking for testing strategies for data oriented code that is quite complex in nature.

As noted by Seb, you can indeed use a range matching:
controller.Setup(x => x.GetById(It.IsInRange<int>(1, 3, Range.Inclusive))))).Returns<int>(i => jobs[i]);
This code uses the argument passed to the method to calculate which value to return.

To get around the "last mock wins" with Moq, you could use the technique from this blog:
Moq Triqs - Successive Expectations
EDIT:
Actually you don't even need that. Based on your example, Moq will return different values based on the method argument.
public interface IController
{
string GetById(int id);
}
class Program
{
static void Main(string[] args)
{
var mockController = new Mock<IController>();
mockController.Setup(x => x.GetById(1)).Returns("one");
mockController.Setup(x => x.GetById(2)).Returns("two");
mockController.Setup(x => x.GetById(3)).Returns("three");
IController controller = mockController.Object;
Console.WriteLine(controller.GetById(1));
Console.WriteLine(controller.GetById(3));
Console.WriteLine(controller.GetById(2));
Console.WriteLine(controller.GetById(3));
Console.WriteLine(controller.GetById(99) == null);
}
}
Output is:
one
three
two
three
True

It sounds like LoaderManagerHandler does... quite a bit of work. "Manager" in a class name always somewhat worries me... from a TDD standpoint, it might be worth thinking about breaking the class up appropriately if possible.
How long is this class?

I've never used Moq, but it seems that it should be able to match a mock invocation by argument(s) supplied.
A quick look at the Quick Start documentation has the following excerpt:
//Matching Arguments
// any value
mock.Setup(foo => foo.Execute(It.IsAny<string>())).Returns(true);
// matching Func<int>, lazy evaluated
mock.Setup(foo => foo.Add(It.Is<int>(i => i % 2 == 0))).Returns(true);
// matching ranges
mock.Setup(foo => foo.Add(It.IsInRange<int>(0, 10, Range.Inclusive))).Returns(true);
I think you should be able to use the second example above.

A simple testing technique is to make sure everytime a bug is logged against a system, make sure a unit test is written covering that case. You can build up a pretty solid set of tests just from that technique. And even better you won't run into the same thing twice.

No matter what I send to jobDetailController.GetById(x) I will always get back jobDetail3
You should spend more time debugging your tests because what is happening is not how Moq behaves. There is a bug in your code or tests causing something to misbehave.
If you want to make repeated calls with the same inputs but different outputs you could also use a different mocking framework. RhinoMocks supports the record/playback idiom. You're right this is not always what you want with regards to enforcing call order. I do prefer Moq myself for its simplicity.

How do you know what to test when writing unit tests? [closed]

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Using C#, I need a class called User that has a username, password, active flag, first name, last name, full name, etc.
There should be methods to authenticate and save a user. Do I just write a test for the methods? And do I even need to worry about testing the properties since they are .Net's getter and setters?

Many great responses to this are also on my question: "Beginning TDD - Challenges? Solutions? Recommendations?"
May I also recommend taking a look at my blog post (which was partly inspired by my question), I have got some good feedback on that. Namely:
I Don’t Know Where to Start?
Start afresh. Only think about writing tests when you are writing new
code. This can be re-working of old
code, or a completely new feature.
Start simple. Don’t go running off and trying to get your head round
a testing framework as well as being
TDD-esque. Debug.Assert works fine.
Use it as a starting point. It doesn’t
mess with your project or create
dependencies.
Start positive. You are trying to improve your craft, feel good about
it. I have seen plenty of developers
out there that are happy to stagnate
and not try new things to better
themselves. You are doing the right
thing, remember this and it will help
stop you from giving up.
Start ready for a challenge. It is quite hard to start getting into
testing. Expect a challenge, but
remember – challenges can be overcome.
Only Test For What You Expect
I had real problems when I first
started because I was constantly sat
there trying to figure out every
possible problem that could occur and
then trying to test for it and fix.
This is a quick way to a headache.
Testing should be a real YAGNI
process. If you know there is a
problem, then write a test for it.
Otherwise, don’t bother.
Only Test One Thing
Each test case should only ever test
one thing. If you ever find yourself
putting “and” in the test case name,
you’re doing something wrong.
I hope this means we can move on from "getters and setters" :)

Test your code, not the language.
A unit test like:
Integer i = new Integer(7);
assert (i.instanceOf(integer));
is only useful if you are writing a compiler and there is a non-zero chance that your instanceof method is not working.
Don't test stuff that you can rely on the language to enforce. In your case, I'd focus on your authenticate and save methods - and I'd write tests that made sure they could handle null values in any or all of those fields gracefully.

This got me into unit testing and it made me very happy
We just started to do unit testing.
For a long time I knew it would be good to start doing it but I had no idea how to start and more importantly what to test.
Then we had to rewrite an important piece of code in our accounting program.
This part was very complex as it involved a lot of different scenarios.
The part I'm talking about is a method to pay sales and/or purchase invoices already entered into the accounting system.
I just didn't know how to start coding it, as there were so many different payment options.
An invoice could be $100 but the customer only transferred $99.
Maybe you have sent sales invoices to a customer but you have also purchased from that customer.
So you sold him for $300 but you bought for $100. You can expect your customer to pay you $200 to settle the balance.
And what if you sold for $500 but the customer pays you only $250?
So I had a very complex problem to solve with many possibilities that one scenario would work perfectly but would be wrong on an other type of invocie/payment combination.
This is where unit testing came to the rescue.
I started to write (inside the test code) a method to create a list of invoices, both for sales and purchases.
Then I wrote a second method to create the actual payment.
Normally a user would enter that information through a user interface.
Then I created the first TestMethod, testing a very simple payment of a single invoice without any payment discounts.
All the action in the system would happen when a bankpayment would be saved to the database.
As you can see I created an invoice, created a payment (a bank transaction) and saved the transaction to disk.
In my asserts I put what should be the correct numbers ending up in the Bank transaction and in the linked Invoice.
I check for the number of payments, the payment amounts, the discount amount and the balance of the invoice after the transaction.
After the test ran I would go to the database and double check if what I expected was there.
After I wrote the test, I started coding the payment method (part of the BankHeader class).
In the coding I only bothered with code to make the first test pass. I did not yet think about the other, more complex, scenarios.
I ran the first test, fixed a small bug until my test would pass.
Then I started to write the second test, this time working with a payment discount.
After I wrote the test I modified the payment method to support discounts.
While testing for correctness with a payment discount, I also tested the simple payment.
Both tests should pass of course.
Then I worked my way down to the more complex scenarios.
1) Think of a new scenario
2) Write a test for that scenario
3) Run that single test to see if it would pass
4) If it didn't I'd debug and modify the code until it would pass.
5) While modifying code I kept on running all tests
This is how I managed to create my very complex payment method.
Without unit testing I did not know how to start coding, the problem seemed overwhelming.
With testing I could start with a simple method and extend it step by step with the assurance that the simpler scenarios would still work.
I'm sure that using unit testing saved me a few days (or weeks) of coding and is more or less guaranteeing the correctness of my method.
If I later think of a new scenario, I can just add it to the tests to see if it is working or not.
If not I can modify the code but still be sure the other scenarios are still working correctly.
This will save days and days in the maintenance and bug fixing phase.
Yes, even tested code can still have bugs if a user does things you did not think of or prevented him from doing
Below are just some of tests I created to test my payment method.
public class TestPayments
{
InvoiceDiaryHeader invoiceHeader = null;
InvoiceDiaryDetail invoiceDetail = null;
BankCashDiaryHeader bankHeader = null;
BankCashDiaryDetail bankDetail = null;
public InvoiceDiaryHeader CreateSales(string amountIncVat, bool sales, int invoiceNumber, string date)
{
......
......
}
public BankCashDiaryHeader CreateMultiplePayments(IList<InvoiceDiaryHeader> invoices, int headerNumber, decimal amount, decimal discount)
{
......
......
......
}
[TestMethod]
public void TestSingleSalesPaymentNoDiscount()
{
IList<InvoiceDiaryHeader> list = new List<InvoiceDiaryHeader>();
list.Add(CreateSales("119", true, 1, "01-09-2008"));
bankHeader = CreateMultiplePayments(list, 1, 119.00M, 0);
bankHeader.Save();
Assert.AreEqual(1, bankHeader.BankCashDetails.Count);
Assert.AreEqual(1, bankHeader.BankCashDetails[0].Payments.Count);
Assert.AreEqual(119M, bankHeader.BankCashDetails[0].Payments[0].PaymentAmount);
Assert.AreEqual(0M, bankHeader.BankCashDetails[0].Payments[0].PaymentDiscount);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[0].InvoiceHeader.Balance);
}
[TestMethod]
public void TestSingleSalesPaymentDiscount()
{
IList<InvoiceDiaryHeader> list = new List<InvoiceDiaryHeader>();
list.Add(CreateSales("119", true, 2, "01-09-2008"));
bankHeader = CreateMultiplePayments(list, 2, 118.00M, 1M);
bankHeader.Save();
Assert.AreEqual(1, bankHeader.BankCashDetails.Count);
Assert.AreEqual(1, bankHeader.BankCashDetails[0].Payments.Count);
Assert.AreEqual(118M, bankHeader.BankCashDetails[0].Payments[0].PaymentAmount);
Assert.AreEqual(1M, bankHeader.BankCashDetails[0].Payments[0].PaymentDiscount);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[0].InvoiceHeader.Balance);
}
[TestMethod]
[ExpectedException(typeof(ApplicationException))]
public void TestDuplicateInvoiceNumber()
{
IList<InvoiceDiaryHeader> list = new List<InvoiceDiaryHeader>();
list.Add(CreateSales("100", true, 2, "01-09-2008"));
list.Add(CreateSales("200", true, 2, "01-09-2008"));
bankHeader = CreateMultiplePayments(list, 3, 300, 0);
bankHeader.Save();
Assert.Fail("expected an ApplicationException");
}
[TestMethod]
public void TestMultipleSalesPaymentWithPaymentDiscount()
{
IList<InvoiceDiaryHeader> list = new List<InvoiceDiaryHeader>();
list.Add(CreateSales("119", true, 11, "01-09-2008"));
list.Add(CreateSales("400", true, 12, "02-09-2008"));
list.Add(CreateSales("600", true, 13, "03-09-2008"));
list.Add(CreateSales("25,40", true, 14, "04-09-2008"));
bankHeader = CreateMultiplePayments(list, 5, 1144.00M, 0.40M);
bankHeader.Save();
Assert.AreEqual(1, bankHeader.BankCashDetails.Count);
Assert.AreEqual(4, bankHeader.BankCashDetails[0].Payments.Count);
Assert.AreEqual(118.60M, bankHeader.BankCashDetails[0].Payments[0].PaymentAmount);
Assert.AreEqual(400, bankHeader.BankCashDetails[0].Payments[1].PaymentAmount);
Assert.AreEqual(600, bankHeader.BankCashDetails[0].Payments[2].PaymentAmount);
Assert.AreEqual(25.40M, bankHeader.BankCashDetails[0].Payments[3].PaymentAmount);
Assert.AreEqual(0.40M, bankHeader.BankCashDetails[0].Payments[0].PaymentDiscount);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[1].PaymentDiscount);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[2].PaymentDiscount);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[3].PaymentDiscount);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[0].InvoiceHeader.Balance);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[1].InvoiceHeader.Balance);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[2].InvoiceHeader.Balance);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[3].InvoiceHeader.Balance);
}
[TestMethod]
public void TestSettlement()
{
IList<InvoiceDiaryHeader> list = new List<InvoiceDiaryHeader>();
list.Add(CreateSales("300", true, 43, "01-09-2008")); //Sales
list.Add(CreateSales("100", false, 6453, "02-09-2008")); //Purchase
bankHeader = CreateMultiplePayments(list, 22, 200, 0);
bankHeader.Save();
Assert.AreEqual(1, bankHeader.BankCashDetails.Count);
Assert.AreEqual(2, bankHeader.BankCashDetails[0].Payments.Count);
Assert.AreEqual(300, bankHeader.BankCashDetails[0].Payments[0].PaymentAmount);
Assert.AreEqual(-100, bankHeader.BankCashDetails[0].Payments[1].PaymentAmount);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[0].InvoiceHeader.Balance);
Assert.AreEqual(0, bankHeader.BankCashDetails[0].Payments[1].InvoiceHeader.Balance);
}

If they really are trivial, then don't bother testing. Eg, if they are implemented like this;
public class User
{
public string Username { get; set; }
public string Password { get; set; }
}
If, on the other hand, you are doing something clever, (like encrypting and decrypting the password in the getter/setter) then give it a test.

The rule is that you have to test every piece of logic you write. If you implemented some specific functionality in the getters and setters I think they are worth testing. If they only assign values to some private fields, don't bother.

This question seems to be a question of where does one draw the line on what methods get tested and which don't.
The setters and getters for value assignment have been created with consistency and future growth in mind, and foreseeing that some time down the road the setter/getter may evolve into more complex operations. It would make sense to put unit tests of those methods in place, also for the sake of consistency and future growth.
Code reliability, especially while undergoing change to add additional functionality, is the primary goal. I am not aware of anyone ever getting fired for including setters/getters in the testing methodology, but I am certain there exists people who wished they had tested methods which last they were aware or can recall were simple set/get wrappers but that was no longer the case.
Maybe another member of the team expanded the set/get methods to include logic that now needs tested but didn't then create the tests. But now your code is calling these methods and you aren't aware they changed and need in-depth testing, and the testing you do in development and QA don't trigger the defect, but real business data on the first day of release does trigger it.
The two teammates will now debate over who dropped the ball and failed to put in unit tests when the set/gets morphed to include logic that can fail but isn't covered by a unit test. The teammate that originally wrote the set/gets will have an easier time coming out of this clean if the tests were implemented from day one on the simple set/gets.
My opinion is that a few minutes of "wasted" time covering ALL methods with unit tests, even trivial ones, might save days of headache down the road and loss of money/reputation of the business and loss of someone's job.
And the fact that you did wrap trivial methods with unit tests might be seen by that junior team mate when they change the trivial methods into non-trivial ones and prompt them to update the test, and now nobody is in trouble because the defect was contained from reaching production.
The way we code, and the discipline that can be seen from our code, can help others.

Another canonical answer. This, I believe, from Ron Jeffries:
Only test the code that you want to work.

Testing boilerplate code is a waste of time, but as Slavo says, if you add a side effect to your getters/setters, then you should write a test to accompany that functionality.
If you're doing test-driven development, you should write the contract (eg interface) first, then write the test(s) to exercise that interface which document the expected results/behaviour. Then write your methods themselves, without touching the code in your unit tests. Finally, grab a code coverage tool and make sure your tests exercise all the logic paths in your code.

Really trivial code like getters and setters that have no extra behaviour than setting a private field are overkill to test. In 3.0 C# even has some syntactic sugar where the compiler takes care of the private field so you don't have to program that.
I usually write lots of very simple tests verifying behaviour I expect from my classes. Even if it's simple stuff like adding two numbers. I switch a lot between writing a simple test and writing some lines of code. The reason for this is that I then can change around code without being afraid I broke things I didn't think about.

You should test everything. Right now you have getters and setters, but one day you might change them somewhat, maybe to do validation or something else. The tests you write today will be used tomorrow to make sure everything keeps on working as usual.
When you write test, you should forget considerations like "right now it's trivial". In an agile or test-driven context you should test assuming future refactoring.
Also, did you try putting in really weird values like extremely long strings, or other "bad" content? Well you should... never assume how badly your code can be abused in the future.
Generally I find that writing extensive user tests is on one side, exhausting. On the other side, though it always gives you invaluable insight on how your application should work and helps you throw away easy (and false) assumptions (like: the user name will always be less than 1000 characters in length).

For simple modules that may end up in a toolkit, or in an open source type of project, you should test as much as possible including the trivial getters and setters. The thing you want to keep in mind is that generating a unit test as you write a particular module is fairly simple and straight forward. Adding getters and setters is minimal code and can be handled without much thought. However, once your code is placed in a larger system, this extra effort can protect you against changes in the underlying system, such as type changes in a base class. Testing everthing is the best way to have a regression that is complete.

It doesn't hurt to write unit tests for your getters and setters. Right now, they may just be doing field get/sets under the hood, but in the future you may have validation logic, or inter-property dependencies that need to be tested. It's easier to write it now while you're thinking about it then remembering to retrofit it if that time ever comes.

in general, when a method is only defined for certain values, test for values on and over the border of what is acceptable. In other words, make sure your method does what it's supposed to do, but nothing more. This is important, because when you're going to fail, you want to fail early.
In inheritance hierarchies, make sure to test for LSP compliance.
Testing default getters and setters doesn't seem very useful to me, unless you're planning to do some validation later on.

well if you think it can break, write a test for it. I usually don't test setter/getter, but lets says you make one for User.Name, which concatenate first and last name, I would write a test so if someone change the order for last and first name, at least he would know he changed something that was tested.

The canonical answer is "test anything that can possibly break." If you are sure the properties won't break, don't test them.
And once something is found to have broken (you find a bug), obviously it means you need to test it. Write a test to reproduce the bug, watch it fail, then fix the bug, then watch the test pass.

As I understand unit tests in the context of agile development, Mike, yes, you need to test the getters and setters (assuming they're publicly visible). The whole concept of unit testing is to test the software unit, which is a class in this case, as a black box. Since the getters and setters are externally visible you need to test them along with Authenticate and Save.

If the Authenticate and Save methods use the properties, then your tests will indirectly touch the properties. As long as the properties are just providing access to data, then explicit testing should not be necessary (unless you are going for 100% coverage).

I would test your getters and setters. Depending on who's writing the code, some people change the meaning of the getter/setter methods. I've seen variable initialization and other validation as part of getter methods. In order to test this sort of thing, you'd want unit tests covering that code explicitly.

Personally I would "test anything that can break" and simple getter (or even better auto properties) will not break. I have never had a simple return statement fail and therefor never have test for them. If the getters have calculation within them or some other form of statements, I would certainly add tests for them.
Personally I use Moq as a mock object framework and then verify that my object calls the surrounding objects the way it should.

You have to cover the execution of every method of the class with UT and check the method return value. This includes getters and setters, especially in case the members(properties) are complex classes, which requires large memory allocation during their initialization. Call the setter with some very large string for example (or something with greek symbols) and check the result is correct (not truncated, encoding is good e.t.c.)
In case of simple integers that also applies - what happens if you pass long instead of integer? That's the reason you write UT for :)

I wouldn't test the actual setting of properties. I would be more concerned about how those properties get populated by the consumer, and what they populate them with. With any testing, you have to weigh the risks with the time/cost of testing.

You should test "every non-trivial block of code" using unit tests as far as possible.
If your properties are trivial and its unlikely that someone will introduce a bug in it, then it should be safe to not unit test them.
Your Authenticate() and Save() methods look like good candidates for testing.

Ideally, you would have done your unit tests as you were writing the class. This is how you're meant to do it when using Test Driven Development. You add the tests as you implement each function point, making sure that you cover the edge-cases with test too.
Writing the tests afterwards is much more painful, but doable.
Here's what I'd do in your position:
Write a basic set of tests that test the core function.
Get NCover and run it on your tests. Your test coverage will probably be around 50% at this point.
Keep adding tests that cover your edge-cases until you get coverage of around 80%-90%
This should give you a nice working set of unit tests that will act as a good buffer against regressions.
The only problem with this approach is that code has to be designed to be testable in this fashion. If you made any coupling mistakes early on, you won't be able to get high coverage very easily.
This is why it is really important to write the tests before you write the code. It forces you to write code that is loosely coupled.

Don't test obviously working (boilerplate) code. So if your setters and getters are just "propertyvalue = value" and "return propertyvalue" it makes no sense to test it.

Even get / set can have odd consequences, depending upon how they have been implemented, so they should be treated as methods.
Each test of these will need to specify sets of parameters for the properties, defining both acceptable and unacceptable properties to ensure the calls return / fail in the expected manner.
You also need to be aware of security gotchas, as an example SQL injection, and test for these.
So yes, you do need to worry about testing the properties.

I believe it's silly to test getters & setters when they only make a simple operation. Personally I don't write complex unit tests to cover any usage pattern. I try to write enough tests to ensure I have handled the normal execution behavior and as much error cases I can think of. I will write more unit tests as a response to bug reports. I use unit test to ensure the code meets the requirements and to make future modification easier. I feel a lot more willing to change code when I know that if I break something a test will fail.

I would write a test for anything that you are writing code for that is testable outside of the GUI interface.
Typically, any logic that I write that has any business logic I place inside another tier or business logic layer.
Then writing tests for anything that does something is easy to do.
First pass, write a unit test for each public method in your "Business Logic Layer".
If I had a class like this:
public class AccountService
{
public void DebitAccount(int accountNumber, double amount)
{
}
public void CreditAccount(int accountNumber, double amount)
{
}
public void CloseAccount(int accountNumber)
{
}
}
The first thing I would do before I wrote any code knowing that I had these actions to perform would be to start writing unit tests.
[TestFixture]
public class AccountServiceTests
{
[Test]
public void DebitAccountTest()
{
}
[Test]
public void CreditAccountTest()
{
}
[Test]
public void CloseAccountTest()
{
}
}
Write your tests to validate the code you've written to do something. If you iterating over a collection of things, and changing something about each of them, write a test that does the same thing and Assert that actually happened.
There's a lot of other approaches you can take, namely Behavoir Driven Development (BDD), that's more involved and not a great place to start with your unit testing skills.
So, the moral of the story is, test anything that does anything you might be worried about, keep the unit tests testing specific things that are small in size, a lot of tests are good.
Keep your business logic outside of the User Interface layer so that you can easily write tests for them, and you'll be good.
I recommend TestDriven.Net or ReSharper as both easily integrate into Visual Studio.

I would recommend writing multiple tests for your Authenticate and Save methods. In addition to the success case (where all parameters are provided, everything is correctly spelled, etc), it's good to have tests for various failure cases (incorrect or missing parameters, unavailable database connections if applicable, etc). I recommend Pragmatic Unit Testing in C# with NUnit as a reference.
As others have stated, unit tests for getters and setters are overkill, unless there's conditional logic in your getters and setters.

Whilst it is possible to correctly guess where your code needs testing, I generally think you need metrics to back up this guess. Unit testing in my view goes hand in hand with code-coverage metrics.
Code with lots of tests but a small coverage hasn't been well tested. That said, code with 100% coverage but not testing the boundry and error cases is also not great.
You want a balance between high coverage (90% minimum) and variable input data.
Remember to test for "garbage in"!
Also, a unit-test is not a unit-test unless it checks for a failure. Unit-tests that don't have asserts or are marked with known exceptions will simply test that the code doesn't die when run!
You need to design your tests so that they always report failures or unexpected/unwanted data!

It makes our code better... period!
One thing us software developers forget about when doing test driven development is the purpose behind our actions. If a unit test is being written after the production code is already in place, the value of the test goes way down (but is not completely lost).
In the true spirit for unit testing, these tests are not primarily there to "test" more of our code; or to get 90%-100% better code coverage. These are all fringe benefits of writing the tests first. The big payoff is that our production code ends be be written much better due to the natural process of TDD.
To help better communicate this idea, the following may be helpful in reading:
The Flawed Theory of Unit Tests
Purposeful Software Development
If we feel that the act of writing more unit tests is what helps us gain a higher quality product, then we may be suffering from a Cargo Cult of Test Driven Development.