public void ReferenceToOtherImmutable()
{
var blackWatch = Watch.Create(color: "black", size: 10);
var personWithBlackWatch = Person.Create(null, watch: blackWatch);
var silverWatch = blackWatch.WithColor("silver");
var personWithSilverWatch = personWithBlackWatch.WithWatch(silverWatch);
Assert.Equal(silverWatch, personWithSilverWatch.Watch);
}
public void PropertiesAreAlsoBuilders()
{
var person = Person.Create("bill", watch: Watch.Create());
var personBuilder = person.ToBuilder();
personBuilder.Watch.Color = "Red";
var modifiedPerson = personBuilder.ToImmutable();
Assert.Equal("Red", modifiedPerson.Watch.Color);
personBuilder.Watch = null;
var personWithoutWatch = personBuilder.ToImmutable();
Assert.Null(personWithoutWatch.Watch);
}