41e93d01ab
Ported from claude/epic-faraday-332679 (6c5889c) — merge was permission-blocked,
same diff applied directly.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
41 lines
1.7 KiB
TypeScript
41 lines
1.7 KiB
TypeScript
import { describe, expect, it } from 'vitest';
|
|
import { TUTORIAL_FADE_MS, TUTORIAL_MS, tutorialAlpha } from '../src/scenes/door/tutorialFade';
|
|
|
|
// Regression guard for the door-tutorial fade. The original implementation was
|
|
// `if (alpha > 0) tweens.add({ alpha: 0, duration: 800 })` inside update():
|
|
// each frame's new tween re-captured the still-positive alpha, so the guard
|
|
// never closed and DoorScene accumulated one live 800ms tween per frame
|
|
// (~1,100 by the end of a night). The fade is now this pure function; these
|
|
// tests pin the property that killed the tween version — it must actually
|
|
// reach 0 and stay there.
|
|
|
|
describe('tutorialAlpha', () => {
|
|
it('holds at full alpha through the tutorial window', () => {
|
|
expect(tutorialAlpha(0)).toBe(1);
|
|
expect(tutorialAlpha(TUTORIAL_MS)).toBe(1);
|
|
});
|
|
|
|
it('fades linearly once the hold expires', () => {
|
|
expect(tutorialAlpha(TUTORIAL_MS + TUTORIAL_FADE_MS / 2)).toBeCloseTo(0.5);
|
|
expect(tutorialAlpha(TUTORIAL_MS + TUTORIAL_FADE_MS / 4)).toBeCloseTo(0.75);
|
|
});
|
|
|
|
it('reaches exactly 0 at fade end and never goes negative after', () => {
|
|
expect(tutorialAlpha(TUTORIAL_MS + TUTORIAL_FADE_MS)).toBe(0);
|
|
expect(tutorialAlpha(TUTORIAL_MS + TUTORIAL_FADE_MS + 1)).toBe(0);
|
|
// A whole night later it is still pinned at 0 — the condition the old
|
|
// tween-spawning guard could never satisfy.
|
|
expect(tutorialAlpha(TUTORIAL_MS + 4 * 60 * 60 * 1000)).toBe(0);
|
|
});
|
|
|
|
it('is monotonically non-increasing frame over frame', () => {
|
|
let prev = Infinity;
|
|
for (let ms = 0; ms < TUTORIAL_MS + 2 * TUTORIAL_FADE_MS; ms += 16.67) {
|
|
const a = tutorialAlpha(ms);
|
|
expect(a).toBeLessThanOrEqual(prev);
|
|
expect(a).toBeGreaterThanOrEqual(0);
|
|
prev = a;
|
|
}
|
|
});
|
|
});
|