protected override Component BuildComponent(Entity entity)
{
StatsComponent result = new StatsComponent();
result.Might = might;
result.Craft = craft;
result.Speed = speed;
return result;
}
public void TestEntitySetup()
{
// Create some components.
Component stats = new StatsComponent();
Component pos = new PosComponent();
Assert.AreEqual(null, stats.Entity);
Assert.AreEqual(null, pos.Entity);
// Create an entity, it starts with nothing but an id.
Entity ent = new Entity("1")
// Give it some components (using a handly fluent interface idiom).
.Set(stats)
.Set(pos);
// Read the components back. Thanks to generic magic, we don't need to
// refer to component families explicitly at all.
StatsComponent stats2;
Assert.IsTrue(ent.TryGet(out stats2));
Assert.AreEqual(stats, stats2);
PosComponent pos2;
Assert.IsTrue(ent.TryGet(out pos2));
Assert.AreEqual(pos, pos2);
Assert.AreEqual(ent, stats.Entity);
Assert.AreEqual(ent, pos.Entity);
// Now for a somewhat subtle pitfall from the generic magic:
try
{
// We declare something as just a Component and try to get it.
Component comp;
ent.TryGet(out comp);
Assert.Fail("Exception didn't happen.");
}
catch(ApplicationException)
{
// The base component class doesn't have a valid family. Trying to get
// a variable without a subcomponent type that has a specified family
// causes a runtime exception.
}
// Another bad thing to do is to add a Component without a proper
// GetFamily method:
try
{
ent.Set(new BadComponent());
Assert.Fail("Exception didn't happen.");
}
catch(ApplicationException)
{
// This also crashes, since the component type fails to describe
// itself properly.
}
// Checking for null components.
try
{
ent.Set(null);
Assert.Fail("Exception didn't happen.");
}
catch(ArgumentNullException)
{
}
// Removing a component.
ent.Clear(pos.Family);
Assert.IsTrue(ent.TryGet(out stats2));
Assert.IsFalse(ent.TryGet(out pos2));
Assert.AreEqual(ent, stats.Entity);
Assert.AreEqual(null, pos.Entity);
}
