public void GivenSubscriptionToTwoLevelPath_WhenRootChanges_NotificationsShouldArrive()
{
var changeSource = new DummyViewModel { Child = new DummyViewModel { Text = "Old text" } };
var sut = new ObservablePropertyChain(changeSource, "Child.Text");
object actualText = null;
sut.Subscribe(o => actualText = o);
changeSource.Child = new DummyViewModel { Text = "This is the real thing" };
Assert.AreEqual("This is the real thing", actualText);
}
public void SubscriptionToTwoLevelPath()
{
var changeSource = new DummyViewModel { Child = new DummyViewModel() };
var sut = new ObservablePropertyChain(changeSource, "Child.Text");
object actualText = null;
sut.Subscribe(o => actualText = o);
changeSource.Child.Text = "Hello world";
Assert.AreEqual("Hello world", actualText);
}
public void GivenSubscriptionToTwoLevelPath_WhenRootChangesButValuesAreSame_NoNotificationIsSent()
{
var changeSource = new DummyViewModel { Child = new DummyViewModel { Text = "Same" } };
var sut = new ObservablePropertyChain(changeSource, "Child.Text");
bool hit = false;
sut.Subscribe(o => hit = true);
changeSource.Child = new DummyViewModel { Text = "Same" };
Assert.IsFalse(hit);
}
