When adding a new component return it instead of the entity itself

[fernandojsg]

Currently addComponent return the entity instead of the component, so you could chain them as:

entity.addComponent(ComponentA).addComponent(ComponentB);

But if you want to set component values directly without passing an object on the addComponent function, it could be nice to return the component directly:

let componentA = entity.addComponent(ComponentA);
componentA.value = 23;

One question would be if we would like that behaviour to be the same as if we would do getMutableComponent so it will trigger the changed. But as we are just creating it, I believe that just triggering the added event should be enough for now.

[robertlong]

Yes, I'd really like addComponent to return the component directly.

I'm not sure what should happen with regard to triggering the changed event. I think I would just handle any logic that deals with the properties in the added event in the same way that I would handle them if I did this addComponent(ComponentA, { some: "props" })

[netpro2k]

Mostly indifferent to returning the component or entity, but it doesn't seem right to be modifying a component ref you didn't get from getMutableComponent so I maybe prefer returning the entity to avoid that confusion. I think if we end up moving pooling out of addComponent you end up passing a component instance into addComponent and so this becomes unnecessary anyway.

[robertlong]

Yeah, just passing the instance is probably fine too. It just depends on how we implement pooling. If addComponent(ComponentA) creates a new instance of ComponentA via its ComponentManager then I'd want addComponent() to return the instance.

If you acquire a new component instance from some other method like world.createComponent(ComponentA) or world.getComponentManager(ComponentA).create() then that would be fine as well. I think this is closely related to how we handle component pooling so maybe we should figure that out first?

[fernandojsg]

Leaving it like this (= returning the entity) in favor to https://github.com/fernandojsg/ecsy/issues/81 to avoid side effects or unwanted use cases as storing a reference to an component or so