use siecs::{Component, World};
#[derive(Component)]
struct Transform;
#[derive(Component)]
struct Renderable;
#[test]
fn world_with_adds_required_component() {
let mut world = World::new();
world.with::<Renderable, Transform>();
let entity = world.entity();
world.add::<Renderable>(entity);
assert!(world.has::<Renderable>(entity));
assert!(world.has::<Transform>(entity));
}