public void ShouldNotifyChangesInHealth()
{
HeroBuilder builder = new HeroBuilder().WithHealth(100);
IHero hero = builder.Build();
INotifyPropertyChanged notifier = hero as INotifyPropertyChanged;
Assert.That(notifier, Is.Not.Null,
"Hero class should implement an interface that enables property change notifications.");
IList <string> changedProperties = new List <string>();
notifier.PropertyChanged += (sender, args) =>
{
changedProperties.Add(args.PropertyName);
};
//trigger Health change
builder.WithHealth(50);
Assert.That(changedProperties.FirstOrDefault(), Is.EqualTo(nameof(IHero.Health)), "A change in Health is not notified.");
}
