What are the best practices for unit testing properties with code in the setter?
- by nportelli
I'm fairly new to unit testing and we are actually attempting to use it on a project. There is a property like this.
public TimeSpan CountDown
{
get
{
return _countDown;
}
set
{
long fraction = value.Ticks % 10000000;
value -= TimeSpan.FromTicks(fraction);
if(fraction > 5000000)
value += TimeSpan.FromSeconds(1);
if(_countDown != value)
{
_countDown = value;
NotifyChanged("CountDown");
}
}
}
My test looks like this.
[TestMethod]
public void CountDownTest_GetSet_PropChangedShouldFire()
{
ManualRafflePresenter target = new ManualRafflePresenter();
bool fired = false;
string name = null;
target.PropertyChanged += new PropertyChangedEventHandler((o, a) =>
{
fired = true;
name = a.PropertyName;
});
TimeSpan expected = new TimeSpan(0, 1, 25);
TimeSpan actual;
target.CountDown = expected;
actual = target.CountDown;
Assert.AreEqual(expected, actual);
Assert.IsTrue(fired);
Assert.AreEqual("CountDown", name);
}
The question is how do I test the code in the setter? Do I break it out into a method? If I do it would probably be private since no one else needs to use this. But they say not to test private methods. Do make a class if this is the only case? would two uses of this code make a class worthwhile? What is wrong with this code from a design standpoint. What is correct?
