public void Subscription_MismatchingPropertyChanged_DoesNotInvokeHandler()
{
TestDerivedObject test = new TestDerivedObject();
bool called = false;
test.SubscribeToPropertyChanged(x => x.ValueProperty, x => called = true);
test.ObjectProperty = new object();
Assert.IsFalse(called, "SubscribeToPropertyChanged should not invoke handler when other properties change");
}
public void Subscription_MatchingPropertyChanged_InvokesHandler()
{
TestDerivedObject test = new TestDerivedObject();
bool called = false;
test.SubscribeToPropertyChanged(x => x.ValueProperty, x => called = true);
test.ValueProperty = 13;
Assert.IsTrue(called, "SubscribeToPropertyChanged should invoke handler when property changes");
}
public void Subscription_ReturnsUnsubscribableDelegate()
{
TestDerivedObject test = new TestDerivedObject();
bool called = false;
var unsubscribe = test.SubscribeToPropertyChanged(x => x.ValueProperty, x => called = true);
test.PropertyChanged -= unsubscribe;
test.ValueProperty = 13;
Assert.IsFalse(called, "SubscribeToPropertyChanged should not invoke handler when unsubscribed");
}
public void TestDerivedSubscription()
{
TestDerivedObject test = new TestDerivedObject();
bool called = false;
// Ensure the PropertyChangedEventHandler.Raise extension method will not fail when its "this" parameter is null
test.ObjectProperty = new object();
test.SubscribeToPropertyChanged(x => x.ValueProperty, x => called = true);
Assert.AreEqual(false, called);
test.ObjectProperty = new object();
Assert.AreEqual(false, called);
test.ValueProperty = 13;
Assert.AreEqual(true, called);
}
