StateView.remove() behaves differently than I expected

[nishiyamaan]

Hi,

I'm building a Colyseus-based card game where cards change visibility depending on gameplay:

• When a card is drawn into a hand, it should become visible to the owner.
• When returned to the deck, it should become hidden again.

To achieve this, I use @view() to selectively expose the cardId field:

export class CardPublic extends Schema {
  @view() @type("string") cardId: string;
  @type("string") zone: string;
  @type("number") index: number;
}

export class BoardState extends Schema {
  @type({ map: CardPublic }) cards = new MapSchema();
}

All cards are pre-populated in room.state.cards at the beginning of the game.
As a result, every client can see all card instances structurally (i.e., they exist in the map), but the cardId field remains hidden unless explicitly exposed via client.view.add(card).

---

Observation

On the client, I set up the following listeners for verification:

$(room.state).cards.onAdd((card, id) => {
  $(card).listen("cardId", (value, preValue) => {
    console.log("cardId changed!!:", value, preValue);
  });
});

$(room.state).cards.onRemove((card, id) => {
  console.log("Card removed:", id);
});

• When I call client.view.add(card) on the server, the listen("cardId") handler is triggered as expected, and the cardId becomes visible.
• When I call client.view.remove(card), I expected cardId to become undefined, and for the listen("cardId") handler to be triggered with undefined as the new value.
  Instead, onRemove is called — the entire card is removed from the client's cards map, even though it still exists on the server.

This results in a refId not found error if the server later updates that card and expects it to still exist on the client.

From the client's point of view, the card appears to have been completely removed from the state, even though it was only meant to become partially hidden (via @view()).
However, performing a full state sync (such as reloading the page) restores the correct card count and visibility.

---

Question

What I originally expected from view.remove(card) was:

• To keep the card object in the client's MapSchema,
• While making only the @view() fields (like cardId) invisible again.

Given that calling view.remove(card) instead removes the entire object from the map,
is there a way to achieve that original intent — hiding specific @view() fields again — without removing the parent object?

If there's a recommended way to implement that kind of behavior, I'd greatly appreciate any guidance.

Thanks in advance!

[endel]

Hi @nishiyamaan, thank you for the detailed feedback. The behaviour you described is not the intended behaviour indeed. I've just created a test case covering this, and fixed it on this commit: colyseus/schema@f1d46b9

Please let me know if upgrading @colyseus/schema fixes this issue for you. Cheers!

[nishiyamaan]

Just updated to the latest @colyseus/schema, and it works perfectly now.
Thank you so much for the quick fix!