public void should_only_execute_system_when_predicate_met()
{
var entityToMatch = Substitute.For <IEntity>();
var idToMatch = 1;
entityToMatch.Id.Returns(idToMatch);
var fakeEntities = new List <IEntity>
{
entityToMatch,
Substitute.For <IEntity>()
};
var mockObservableGroup = Substitute.For <IObservableGroup>();
mockObservableGroup.GetEnumerator().Returns(fakeEntities.GetEnumerator());
mockObservableGroup[0].Returns(fakeEntities[0]);
mockObservableGroup[1].Returns(fakeEntities[1]);
mockObservableGroup.Count.Returns(fakeEntities.Count);
var observableGroupManager = Substitute.For <IObservableGroupManager>();
var threadHandler = Substitute.For <IThreadHandler>();
var observableScheduler = Substitute.For <IUpdateScheduler>();
var observableSubject = new Subject <ElapsedTime>();
observableScheduler.OnUpdate.Returns(observableSubject);
var fakeGroup = new GroupWithPredicate(x => x.Id == idToMatch);
observableGroupManager.GetObservableGroup(Arg.Is(fakeGroup), Arg.Any <int[]>()).Returns(mockObservableGroup);
var mockSystem = Substitute.For <IBasicEntitySystem>();
mockSystem.Group.Returns(fakeGroup);
var systemHandler = new BasicEntitySystemHandler(observableGroupManager, threadHandler, observableScheduler);
systemHandler.SetupSystem(mockSystem);
observableSubject.OnNext(new ElapsedTime());
mockSystem.ReceivedWithAnyArgs(1).Process(Arg.Is(entityToMatch));
Assert.Equal(1, systemHandler._systemSubscriptions.Count);
Assert.NotNull(systemHandler._systemSubscriptions[mockSystem]);
}
