nEngine/packages/core/test/time.test.ts

import { describe, expect, it } from "vitest";
import { ContentRegistry, TimeSystem, World, WorldEventBus, type TimeDef } from "../src/index.js";

function setup() {
  const registry = new ContentRegistry();
  const world = new World();
  const events = new WorldEventBus();
  const timeDef: TimeDef = {
    id: "default",
    dayLengthTicks: 4,
    seasons: [
      { name: "spring", dayCount: 3 },
      { name: "summer", dayCount: 3 },
    ],
    start: { day: 1, season: "spring" },
  };
  registry.register("time", timeDef);
  const ts = new TimeSystem();
  ts.init({ world, registry, events });
  return { ts, events };
}

describe("TimeSystem", () => {
  it("starts from the TimeDef start state", () => {
    const { ts } = setup();
    expect(ts.get()).toEqual({ day: 1, season: "spring", tickInDay: 0 });
  });

  it("advance across a day boundary emits day-start", () => {
    const { ts, events } = setup();
    const seen: unknown[] = [];
    events.on("day-start", (p) => seen.push(p));

    ts.advance(3);
    expect(seen).toHaveLength(0);
    expect(ts.get()).toEqual({ day: 1, season: "spring", tickInDay: 3 });

    ts.advance(1);
    expect(seen).toHaveLength(1);
    expect(seen[0]).toEqual({ day: 2, season: "spring" });
    expect(ts.get()).toEqual({ day: 2, season: "spring", tickInDay: 0 });
  });

  it("advance across a season boundary emits season-change", () => {
    const { ts, events } = setup();
    const seen: unknown[] = [];
    events.on("season-change", (p) => seen.push(p));

    ts.advance(4 * 3);
    expect(seen).toHaveLength(1);
    expect(seen[0]).toEqual({ day: 1, season: "summer" });
    expect(ts.get()).toEqual({ day: 1, season: "summer", tickInDay: 0 });
  });

  it("advance across a season boundary also emits day-start for the new day", () => {
    const { ts, events } = setup();
    const days: unknown[] = [];
    const seasons: unknown[] = [];
    events.on("day-start", (p) => days.push(p));
    events.on("season-change", (p) => seasons.push(p));

    ts.advance(4 * 3);
    expect(seasons).toHaveLength(1);
    expect(days).toHaveLength(3);
    expect(days[2]).toEqual({ day: 1, season: "summer" });
  });

  it("set jumps directly without emitting", () => {
    const { ts, events } = setup();
    const seen: unknown[] = [];
    events.on("day-start", (p) => seen.push(p));
    events.on("season-change", (p) => seen.push(p));

    ts.set(10, "winter");
    expect(ts.get()).toEqual({ day: 10, season: "winter", tickInDay: 0 });
    expect(seen).toHaveLength(0);
  });
});