nEngine/packages/core/test/world.test.ts

import { describe, expect, it } from "vitest";
import { World, type Entity } from "../src/index.js";

describe("World", () => {
  it("create/get/query/remove/snapshot roundtrip", () => {
    const world = new World();

    world.create({ id: "player", type: "player", x: 1, y: 2 });
    world.create({ id: "farm", type: "map", width: 12 });
    world.create({ id: "plot-1", type: "plot", x: 3, y: 3 });

    expect(world.get("player")).toEqual({ id: "player", type: "player", x: 1, y: 2 });
    expect(world.get("missing")).toBeUndefined();

    const players = world.query({ type: "player" });
    expect(players).toHaveLength(1);
    expect(players[0]?.id).toBe("player");

    const all = world.query();
    expect(all).toHaveLength(3);
    expect(world.snapshot()).toHaveLength(3);

    expect(world.remove("plot-1")).toBe(true);
    expect(world.remove("plot-1")).toBe(false);
    expect(world.get("plot-1")).toBeUndefined();
    expect(world.snapshot()).toHaveLength(2);

    const entity: Entity = world.create({ id: "plot-2", type: "plot", x: 0 });
    expect(entity).toBe(world.get("plot-2"));
  });
});