feuerwerk/tests/core/audio-switch.test.ts

import { describe, expect, it } from 'vitest';
import { AudioSwitch, DIVERTED_IDS } from '../../src/runtime/audioSwitch';
import { type AudioSink, SILENT_AUDIO } from '../../src/runtime/systems/Audio';

/** A sink that numbers its plays from `first` and writes down every call, with its clock at `clock`. */
function sinkFrom(first: number, clock = 0) {
  const calls: string[] = [];
  let next = first;
  const sink: AudioSink & { calls: string[]; clockAt: number } = {
    ...SILENT_AUDIO,
    calls,
    clockAt: clock,
    play: (file) => (calls.push(`play ${file}`), next++),
    playSequence: (name) => (calls.push(`sequence ${name}`), next++),
    stopVoice: (voice) => void calls.push(`stopVoice ${voice}`),
    stopPlayback: (id) => void calls.push(`stopPlayback ${id}`),
    tune: (voice) => void calls.push(`tune ${voice}`),
    stop: (file) => void calls.push(`stop ${file}`),
    stopOwner: (owner) => void calls.push(`stopOwner ${owner}`),
    setMix: (buses) => void calls.push(`setMix ${buses.map((bus) => bus.name).join(',')}`),
    setMixVolume: (bus, volume) => void calls.push(`setMixVolume ${bus} ${volume}`),
    resetMix: () => void calls.push('resetMix'),
    length: () => 2,
    clock: () => sink.clockAt,
  };
  return sink;
}

describe('AudioSwitch (#423)', () => {
  it('plays live until it is diverted, and reaches each voice in the sink that numbered it', () => {
    const live = sinkFrom(1);
    const aside = sinkFrom(DIVERTED_IDS);
    const audio = new AudioSwitch(live);
    const before = audio.play('music', 1, true, '');
    audio.divert(aside);
    const after = audio.play('hit', 1, false, '');
    expect(before).toBe(1);
    expect(after).toBe(DIVERTED_IDS);
    audio.tune(before, {});
    audio.stopVoice(after);
    expect(live.calls).toEqual(['play music', 'tune 1']);
    expect(aside.calls).toEqual(['play hit', `stopVoice ${DIVERTED_IDS}`]);
    audio.restore();
    expect(audio.play('again', 1, false, '')).toBe(2);
    // One of the diverted sink, gone since, reaches nobody.
    audio.stopVoice(after);
    expect(aside.calls).toHaveLength(2);
  });

  it('stops by name, owner and everything in both, and hands the mix as it stands to the one it diverts to', () => {
    const live = sinkFrom(1);
    const aside = sinkFrom(DIVERTED_IDS);
    const audio = new AudioSwitch(live);
    audio.setMix([{ name: 'mix', volume: 1, into: null, fx: null }]);
    audio.setMixVolume('mix:music', 0.5);
    audio.divert(aside);
    expect(aside.calls).toEqual(['setMix mix', 'setMixVolume mix:music 0.5']);
    audio.stop('');
    audio.stopOwner('o1');
    expect(live.calls.slice(-2)).toEqual(['stop ', 'stopOwner o1']);
    expect(aside.calls.slice(-2)).toEqual(['stop ', 'stopOwner o1']);
    // The live sink knows every file, a streamed one too.
    expect(audio.length('long')).toBe(2);
  });

  it('keeps time by the sink it plays to', () => {
    const live = sinkFrom(1, 5);
    const aside = sinkFrom(DIVERTED_IDS, 0.25);
    const audio = new AudioSwitch(live);
    const music = audio.playSequence('composition:c', {} as never, '');
    expect(audio.clock()).toBe(5);
    audio.divert(aside);
    expect(audio.clock()).toBe(0.25);
    // A composition that meets its picture again stops its live playing and starts on the other.
    audio.stopPlayback(music, 0.02);
    audio.playSequence('composition:c', {} as never, '');
    expect(live.calls).toEqual(['sequence composition:c', 'stopPlayback 1']);
    expect(aside.calls).toEqual(['sequence composition:c']);
  });

  it('lands a stinger only on the clock of the sink it plays in (#338)', () => {
    const live = { ...sinkFrom(1, 5), landOn: () => 6 };
    const aside = { ...sinkFrom(DIVERTED_IDS, 0.25), landOn: () => 0.5 };
    const audio = new AudioSwitch(live);
    const song = audio.playSequence('song:s', {} as never, '');
    expect(audio.landOn(song, () => 0)).toBe(6);
    audio.divert(aside);
    // The song plays on live, the stinger would play diverted: the two clocks do not meet.
    expect(audio.landOn(song, () => 0)).toBeNull();
    const there = audio.playSequence('song:s', {} as never, '');
    expect(audio.landOn(there, () => 0)).toBe(0.5);
  });
});