feuerwerk/tests/core/soundfx.test.ts

/**
 * A sound FX asset (#311) is a graph a sound is played through: Input, effects, Output. It never
 * runs as a behavior does – the compiler turns it into the line of effects a voice passes.
 */
import { describe, expect, it } from 'vitest';
import { buildAsset, CreateAssetCommand, CreateSoundCommand } from '../../src/core/commands/assetCommands';
import { RenamePortCommand, SetPortDefaultCommand } from '../../src/core/commands/portCommands';
import { callProblem, resolveDef, soundFxParamsMismatch } from '../../src/core/graph';
import { type DeclaredPort, portsCompatible } from '../../src/core/graph/Graph';
import { graphLookup } from '../../src/core/model/graphLookup';
import type { BehaviorAsset, SoundFxAsset } from '../../src/core/model/Asset';
import { isPlaceableType } from '../../src/core/model/AssetTypes';
import { assetRefChoices } from '../../src/core/properties/assetRef';
import { compileSoundFx, soundFxBuildFor } from '../../src/core/soundfx/compile';
import {
  DRY,
  EMPTY_PLAN,
  type FxChain,
  fxChainOf,
  type FxPlan,
  type FxVoice,
} from '../../src/core/soundfx/nodes';
import { deserializeProject } from '../../src/core/store/serialize';
import type { AudioSink } from '../../src/runtime/systems/Audio';
import { paletteEntries } from '../../src/editor/graph/paletteEntries';
import {
  graphEditor,
  makeBehavior,
  makeProject,
  makeSpriteScene,
  place,
  type ProjectFixture,
  roundTrip,
  startWorld,
} from '../helpers';

const FILE = `${'a1'.repeat(32)}.wav`;

/** The pitch of a sound that is not mixed. */
const pitchOf = <T extends FxChain | FxPlan>(sound: T) => ('pitch' in sound ? sound.pitch : undefined);

function makeFx(f: ProjectFixture = makeProject()) {
  const command = new CreateAssetCommand('soundfx', 'Cave');
  f.stack.execute(command);
  const fx = command.asset as SoundFxAsset;
  return { ...f, fx, edit: graphEditor(f, fx as unknown as BehaviorAsset) };
}

/** Input, the given effects in a row, Output. */
function line(effects: { type: string; params?: Record<string, number> }[]) {
  const f = makeFx();
  const input = f.edit.addNode('SoundFxInput');
  let tail = input;
  for (const effect of effects) {
    const node = f.edit.addNode(effect.type, effect.params ?? {});
    f.edit.connect(tail, 'out', node, 'in');
    tail = node;
  }
  const output = f.edit.addNode('SoundFxOutput');
  f.edit.connect(tail, 'out', output, 'in');
  return { ...f, input, output };
}

describe('the sound FX asset', () => {
  it('is not placeable, starts with an empty graph and is what the fx picker offers', () => {
    expect(isPlaceableType('soundfx')).toBe(false);
    expect(buildAsset('soundfx', 'FX')).toMatchObject({ type: 'soundfx', graph: { nodes: [], edges: [] } });
    const f = makeFx();
    f.stack.execute(new CreateSoundCommand('Jump', FILE));
    expect(assetRefChoices(f.project, ['soundfx']).map((a) => a.id)).toEqual([f.fx.id]);
  });

  it('survives a round trip and keeps only sound FX nodes', () => {
    const f = line([{ type: 'SoundFxGain', params: { gain: -6 } }]);
    expect(roundTrip(f.project)).toEqual(f.project);

    const loaded = deserializeProject({
      name: 'P',
      assets: [
        {
          id: 'fx',
          type: 'soundfx',
          name: 'FX',
          graph: {
            nodes: [
              { id: 'a', type: 'SoundFxInput', x: 0, y: 0, params: {} },
              { id: 'b', type: 'OnStart', x: 0, y: 0, params: {} },
            ],
            edges: [],
          },
        },
      ],
    });
    expect((loaded.assets[0] as SoundFxAsset).graph.nodes.map((n) => n.id)).toEqual(['a']);
  });

  it('carries sound only from a sound port into a sound port', () => {
    expect(portsCompatible('audio', 'audio')).toBe(true);
    expect(portsCompatible('audio', 'any')).toBe(false);
    expect(portsCompatible('number', 'audio')).toBe(false);
    expect(portsCompatible('any', 'audio')).toBe(false);
  });

  it('offers its effects, Input and Output once each, and none of them in a behavior', () => {
    const f = makeFx();
    const ids = () => paletteEntries(f.project, f.fx).map((e) => e.id);
    expect(ids()).toEqual([
      'SoundFxInput',
      'SoundFxOutput',
      'SoundFxGain',
      'SoundFxPitch',
      'SoundFxEq',
      'SoundFxMix',
    ]);
    f.edit.addNode('SoundFxInput');
    f.edit.addNode('SoundFxOutput');
    expect(ids()).toEqual(['SoundFxGain', 'SoundFxPitch', 'SoundFxEq', 'SoundFxMix']);

    const behavior = makeBehavior(f, 'Logic');
    expect(paletteEntries(f.project, behavior).some((e) => e.def.category === 'sound')).toBe(false);
  });
});

describe('compiling a sound FX graph', () => {
  it('needs an Output, and an Output fed from the Input', () => {
    const f = makeFx();
    expect(compileSoundFx(f.fx.graph)).toMatchObject({ compiled: null, reason: 'No Output node' });

    const output = f.edit.addNode('SoundFxOutput');
    const gain = f.edit.addNode('SoundFxGain');
    f.edit.connect(gain, 'out', output, 'in');
    const build = compileSoundFx(f.fx.graph);
    expect(build.compiled).toBeNull();
    expect(build.problems[gain.id]).toBe('Nothing comes in: connect it to the Input');
  });

  it('passes the sound on untouched through Input and Output alone', () => {
    const build = compileSoundFx(line([]).fx.graph);
    expect(build).toMatchObject({ compiled: EMPTY_PLAN, effects: 0, reason: '' });
    expect(fxChainOf(build.compiled!)).toEqual(DRY);
  });

  it('turns every node on the line into its stages, in order', () => {
    const f = line([
      { type: 'SoundFxGain', params: { gain: -6 } },
      { type: 'SoundFxPitch', params: { semitones: 12 } },
      { type: 'SoundFxEq', params: { low: 6, high: -3 } },
      { type: 'SoundFxPitch', params: { semitones: -5 } },
    ]);
    const build = compileSoundFx(f.fx.graph);
    expect(build.effects).toBe(4);
    const chain = fxChainOf(build.compiled!);
    expect(pitchOf(chain)).toBe(7);
    expect(chain.stages).toHaveLength(3);
    expect(chain.stages[0]!.kind).toBe('gain');
    expect(chain.stages[0]!.gain).toBeCloseTo(0.501, 3);
    expect(chain.stages.slice(1)).toEqual([
      { kind: 'filter', filter: 'lowshelf', frequency: 80, gain: 6, q: 1 },
      { kind: 'filter', filter: 'highshelf', frequency: 12000, gain: -3, q: 1 },
    ]);
  });

  it('leaves out what does nothing and holds a value to its row', () => {
    const quiet = compileSoundFx(line([{ type: 'SoundFxGain' }, { type: 'SoundFxEq' }]).fx.graph);
    expect(quiet.compiled).toEqual(EMPTY_PLAN);
    expect(quiet.effects).toBe(2);

    const loud = fxChainOf(
      compileSoundFx(line([{ type: 'SoundFxGain', params: { gain: 200 } }]).fx.graph).compiled!,
    );
    expect(loud.stages[0]!.gain).toBeCloseTo(10 ** (24 / 20));
  });

  it('ignores a node hanging off the line', () => {
    const f = line([{ type: 'SoundFxPitch', params: { semitones: 3 } }]);
    const aside = f.edit.addNode('SoundFxGain', { gain: -20 });
    f.edit.connect(f.input, 'out', aside, 'in');
    const build = compileSoundFx(f.fx.graph);
    expect(fxChainOf(build.compiled!)).toEqual({ pitch: 3, shifted: true, stages: [] });
    expect(build.effects).toBe(1);
  });
});

describe('a Mix in a sound FX graph (#316)', () => {
  /** Input → Pitch +12 → Mix a, Input → Gain -6 → Mix b, Mix → EQ → Output. */
  function forked(mix: Record<string, number> = {}) {
    const f = makeFx();
    const input = f.edit.addNode('SoundFxInput');
    const pitch = f.edit.addNode('SoundFxPitch', { semitones: 12 });
    const gain = f.edit.addNode('SoundFxGain', { gain: -6 });
    const node = f.edit.addNode('SoundFxMix', mix);
    const eq = f.edit.addNode('SoundFxEq', { low: 6 });
    const output = f.edit.addNode('SoundFxOutput');
    f.edit.connect(input, 'out', pitch, 'in');
    f.edit.connect(input, 'out', gain, 'in');
    f.edit.connect(pitch, 'out', node, 'a');
    f.edit.connect(gain, 'out', node, 'b');
    f.edit.connect(node, 'out', eq, 'in');
    f.edit.connect(eq, 'out', output, 'in');
    return { ...f, input, mix: node };
  }

  it('joins two ways from the Input, each with its own pitch, half each by default', () => {
    const build = compileSoundFx(forked().fx.graph);
    expect(build).toMatchObject({ effects: 4, reason: '' });
    const chain = fxChainOf(build.compiled!);
    expect(chain).toMatchObject({
      mix: 0.5,
      a: { pitch: 12, stages: [] },
      b: { pitch: 0, stages: [{ kind: 'gain' }] },
      stages: [{ kind: 'filter', filter: 'lowshelf', gain: 6 }],
    });
  });

  it('is only the one sound at 0 or 1, with what follows the Mix', () => {
    expect(fxChainOf(compileSoundFx(forked({ mix: 0 }).fx.graph).compiled!)).toMatchObject({
      pitch: 12,
      stages: [{ kind: 'filter' }],
    });
    const b = fxChainOf(compileSoundFx(forked({ mix: 5 }).fx.graph).compiled!);
    expect(b).toMatchObject({ pitch: 0, stages: [{ kind: 'gain' }, { kind: 'filter' }] });
  });

  it('takes its share from a parameter, held between 0 and 1, and keeps both ways for it (#315)', () => {
    const f = forked();
    f.input.ports = [{ key: 'blend', kind: 'number', default: 0.25 }];
    f.edit.connect(f.input, 'blend', f.mix, 'mix');
    const plan = compileSoundFx(f.fx.graph).compiled!;
    expect(fxChainOf(plan)).toMatchObject({ mix: 0.25 });
    expect(fxChainOf(plan, { blend: 0.8 })).toMatchObject({ mix: 0.8 });
    expect(fxChainOf(plan, { blend: -3 })).toMatchObject({ mix: 0, a: { pitch: 12 }, b: { pitch: 0 } });
    expect(fxChainOf(plan, { blend: 3 })).toMatchObject({ mix: 1, a: { pitch: 12 }, b: { pitch: 0 } });
  });

  it('hands a Pitch behind it to both of its sounds', () => {
    const f = forked();
    const output = f.fx.graph.nodes.find((n) => n.type === 'SoundFxOutput')!;
    const eq = f.fx.graph.nodes.find((n) => n.type === 'SoundFxEq')!;
    f.fx.graph.edges = f.fx.graph.edges.filter((e) => e.to.node !== output.id);
    const after = f.edit.addNode('SoundFxPitch', { semitones: -5 });
    f.edit.connect(eq, 'out', after, 'in');
    f.edit.connect(after, 'out', output, 'in');
    expect(fxChainOf(compileSoundFx(f.fx.graph).compiled!)).toMatchObject({
      a: { pitch: 7 },
      b: { pitch: -5 },
      stages: [{ kind: 'filter' }],
    });
  });

  it('needs both of its sounds', () => {
    const f = forked();
    f.fx.graph.edges = f.fx.graph.edges.filter((e) => !(e.to.node === f.mix.id && e.to.port === 'b'));
    const build = compileSoundFx(f.fx.graph);
    expect(build.compiled).toBeNull();
    expect(build.problems[f.mix.id]).toBe('Nothing comes in: connect it to the Input');
  });
});

/**
 * Records what it was asked to play, with the line of effects its values make, and every tune with
 * its time on the side. A voice is numbered by how many have been played, so the first is 1. Every
 * file lasts a quarter of a second.
 */
function fakeAudio(): AudioSink & {
  played: { file: string; owner: string; fx: FxChain | undefined }[];
  tuned: { voice: number; params: Readonly<Record<string, number>> }[];
  times: (number | undefined)[];
} {
  const sink = {
    played: [] as { file: string; owner: string; fx: FxChain | undefined }[],
    tuned: [] as { voice: number; params: Readonly<Record<string, number>> }[],
    times: [] as (number | undefined)[],
    play: (file: string, _volume: number, _loop: boolean, owner: string, fx?: FxVoice) =>
      sink.played.push({ file, owner, fx: fx && fxChainOf(fx.plan, fx.params) }),
    tune: (voice: number, params: Readonly<Record<string, number>>, time?: number) => {
      sink.tuned.push({ voice, params });
      sink.times.push(time);
    },
    length: () => 0.25,
    stop: () => {},
    stopOwner: () => {},
  };
  return sink;
}

describe('Play sound with fx', () => {
  function playingScene(fxId: (f: ReturnType<typeof makeFx>) => string) {
    const scene = makeSpriteScene('Box');
    const withFx = makeFx(scene);
    const fx = withFx.fx;
    const input = withFx.edit.addNode('SoundFxInput');
    const pitch = withFx.edit.addNode('SoundFxPitch', { semitones: -12 });
    const output = withFx.edit.addNode('SoundFxOutput');
    withFx.edit.connect(input, 'out', pitch, 'in');
    withFx.edit.connect(pitch, 'out', output, 'in');
    const sound = new CreateSoundCommand('Jump', FILE);
    scene.stack.execute(sound);
    const behavior = makeBehavior(scene, 'Logic');
    place(scene, behavior.id, { x: 0, y: 0 }, place(scene, scene.spriteId, { x: 0, y: 0 }));
    const edit = graphEditor(scene, behavior);
    const start = edit.addNode('OnStart');
    const play = edit.addNode('PlaySound', { sound: sound.asset.id, fx: fxId(withFx) });
    edit.connect(start, 'exec', play, 'exec');
    return { ...scene, fx, output, pitch };
  }

  it('sends the voice through the asset the node names', () => {
    const f = playingScene((s) => s.fx.id);
    const audio = fakeAudio();
    startWorld(f, { behaviors: true, audio }).frame();
    expect(audio.played).toMatchObject([{ file: FILE, fx: { pitch: -12, stages: [] } }]);
  });

  it('plays it dry without an fx, with one that is gone, and with one that does not compile', () => {
    const none = fakeAudio();
    startWorld(
      playingScene(() => ''),
      { behaviors: true, audio: none },
    ).frame();
    const gone = fakeAudio();
    startWorld(
      playingScene(() => 'no-such-fx'),
      { behaviors: true, audio: gone },
    ).frame();
    const broken = playingScene((s) => s.fx.id);
    broken.fx.graph.edges = [];
    expect(soundFxBuildFor(broken.fx).compiled).toBeNull();
    const brokenAudio = fakeAudio();
    startWorld(broken, { behaviors: true, audio: brokenAudio }).frame();
    for (const audio of [none, gone, brokenAudio])
      expect(audio.played).toMatchObject([{ file: FILE, fx: DRY }]);
  });
});

/** Input with the given parameters, its `param` fed into the effect's `into`, then Output. */
function withParam(type: string, into: string, ports: DeclaredPort[], param = ports[0]!.key) {
  const f = line([{ type }]);
  f.input.ports = ports;
  const effect = f.fx.graph.nodes.find((n) => n.type === type)!;
  f.edit.connect(f.input, param, effect, into);
  return f;
}

describe('the parameters of a sound FX', () => {
  it('stay open in the plan and take the value handed in, held to the row', () => {
    const f = withParam('SoundFxPitch', 'semitones', [{ key: 'depth', kind: 'number', default: -12 }]);
    const plan = soundFxBuildFor(f.fx).compiled!;
    expect(pitchOf(plan)).toEqual([{ value: -12, param: 'depth', min: -64, max: 64 }]);
    expect(pitchOf(fxChainOf(plan))).toBe(-12);
    expect(pitchOf(fxChainOf(plan, { depth: 5 }))).toBe(5);
    expect(pitchOf(fxChainOf(plan, { depth: 100 }))).toBe(64);
    expect(pitchOf(fxChainOf(plan, { other: 3 }))).toBe(-12);
  });

  it('keep a stage that is 0 by default, so a value handed in can open it, even on a playing voice', () => {
    const f = withParam('SoundFxGain', 'gain', [{ key: 'loud', kind: 'number' }]);
    const plan = soundFxBuildFor(f.fx).compiled!;
    expect(plan.stages).toHaveLength(1);
    expect(fxChainOf(plan)).toEqual({ pitch: 0, shifted: false, stages: [{ kind: 'gain', gain: 1 }] });
    expect(fxChainOf(plan, { loud: 6 }).stages[0]).toMatchObject({ kind: 'gain' });
    expect((fxChainOf(plan, { loud: 6 }).stages[0] as { gain: number }).gain).toBeCloseTo(10 ** (6 / 20));
  });

  it('keep a pitch that is 0 by default on the worklet, and only a typed-in 0 off it (#317)', () => {
    const fed = withParam('SoundFxPitch', 'semitones', [{ key: 'depth', kind: 'number' }]);
    expect(fxChainOf(soundFxBuildFor(fed.fx).compiled!)).toMatchObject({ pitch: 0, shifted: true });
    const typed = line([{ type: 'SoundFxPitch', params: { semitones: 0 } }]);
    expect(fxChainOf(soundFxBuildFor(typed.fx).compiled!)).toMatchObject({ pitch: 0, shifted: false });
  });

  it('feed an EQ band as well', () => {
    const f = withParam('SoundFxEq', 'mid', [{ key: 'body', kind: 'number', default: 3 }]);
    const chain = fxChainOf(soundFxBuildFor(f.fx).compiled!, { body: -4 });
    expect(chain.stages).toEqual([{ kind: 'filter', filter: 'peaking', frequency: 1000, gain: -4, q: 1 }]);
  });

  it('are kept with their defaults through a save, a default only on a number', () => {
    const f = withParam('SoundFxPitch', 'semitones', [{ key: 'depth', kind: 'number', default: -7 }]);
    expect(roundTrip(f.project)).toEqual(f.project);
    const loaded = deserializeProject({
      name: 'P',
      assets: [
        {
          id: 'fx',
          type: 'soundfx',
          name: 'FX',
          graph: {
            nodes: [
              {
                id: 'a',
                type: 'SoundFxInput',
                x: 0,
                y: 0,
                params: {},
                ports: [
                  { key: 'p', kind: 'number', default: 'loud' },
                  { key: 'q', kind: 'number', default: 2 },
                ],
              },
            ],
            edges: [],
          },
        },
      ],
    });
    expect((loaded.assets[0] as SoundFxAsset).graph.nodes[0]!.ports).toEqual([
      { key: 'p', kind: 'number' },
      { key: 'q', kind: 'number', default: 2 },
    ]);
  });

  it('do not go where a sound goes, and a sound does not go where a number does', () => {
    const f = line([{ type: 'SoundFxGain' }]);
    f.input.ports = [{ key: 'level', kind: 'number' }];
    const gain = f.fx.graph.nodes.find((n) => n.type === 'SoundFxGain')!;
    f.fx.graph.edges.find((e) => e.to.node === gain.id)!.from.port = 'level';
    expect(compileSoundFx(f.fx.graph).problems[gain.id]).toBe('"in" takes a sound');
    expect(portsCompatible('fxparams', 'fxparams')).toBe(true);
    expect(portsCompatible('fxparams', 'any')).toBe(false);
    expect(portsCompatible('struct', 'fxparams')).toBe(false);
  });

  it('have a default set by a command that undoes', () => {
    const f = withParam('SoundFxPitch', 'semitones', [{ key: 'depth', kind: 'number' }]);
    f.stack.execute(new SetPortDefaultCommand(f.fx.id, f.input.id, 'depth', 4));
    expect(f.input.ports).toEqual([{ key: 'depth', kind: 'number', default: 4 }]);
    expect(pitchOf(fxChainOf(soundFxBuildFor(f.fx).compiled!))).toBe(4);
    f.stack.undo();
    expect(f.input.ports).toEqual([{ key: 'depth', kind: 'number' }]);
  });
});

describe('Sound FX parameters and Play sound', () => {
  function scene(options: { pick?: string[]; values?: Record<string, number>; other?: boolean } = {}) {
    const f = makeSpriteScene('Box');
    const withFx = makeFx(f);
    const { fx, edit: fxEdit } = withFx;
    const input = fxEdit.addNode('SoundFxInput');
    input.ports = [
      { key: 'depth', kind: 'number', default: -12 },
      { key: 'loud', kind: 'number', default: 0 },
    ];
    const pitch = fxEdit.addNode('SoundFxPitch');
    const gain = fxEdit.addNode('SoundFxGain');
    const output = fxEdit.addNode('SoundFxOutput');
    fxEdit.connect(input, 'out', pitch, 'in');
    fxEdit.connect(pitch, 'out', gain, 'in');
    fxEdit.connect(gain, 'out', output, 'in');
    fxEdit.connect(input, 'depth', pitch, 'semitones');
    fxEdit.connect(input, 'loud', gain, 'gain');
    const sound = new CreateSoundCommand('Jump', FILE);
    f.stack.execute(sound);
    const behavior = makeBehavior(f, 'Logic');
    place(f, behavior.id, { x: 0, y: 0 }, place(f, f.spriteId, { x: 0, y: 0 }));
    const edit = graphEditor(f, behavior);
    const start = edit.addNode('OnStart');
    const play = edit.addNode('PlaySound', { sound: sound.asset.id, fx: fx.id });
    const named = options.other ? 'another-fx' : fx.id;
    const params = edit.addNode('SoundFxParameters', { soundFxAsset: named, ...options.values });
    params.ports = (options.pick ?? []).map((key) => ({ key, kind: 'number' as const }));
    edit.connect(start, 'exec', play, 'exec');
    edit.connect(params, 'params', play, 'fxParams');
    return { ...f, fx, input, behavior, play, params };
  }

  it('hands the picked values to the voice, the others keep their defaults', () => {
    const f = scene({ pick: ['depth'], values: { depth: 7 } });
    const audio = fakeAudio();
    startWorld(f, { behaviors: true, audio }).frame();
    expect(audio.played).toMatchObject([
      { file: FILE, fx: { pitch: 7, stages: [{ kind: 'gain', gain: 1 }] } },
    ]);
  });

  it('starts a picked parameter at the default of the FX', () => {
    const f = scene({ pick: ['depth', 'loud'] });
    const def = resolveDef(f.params, f.behavior.graph, graphLookup(f.project))!;
    expect(def.inputs.map((p) => [p.key, p.default])).toEqual([
      ['depth', -12],
      ['loud', 0],
    ]);
    const audio = fakeAudio();
    startWorld(f, { behaviors: true, audio }).frame();
    expect(audio.played[0]!.fx).toEqual({ pitch: -12, shifted: true, stages: [{ kind: 'gain', gain: 1 }] });
  });

  it('says so at the node when no FX is picked or it is gone', () => {
    const f = scene();
    const lookup = graphLookup(f.project);
    expect(callProblem(f.params, lookup)).toBeNull();
    f.params.params.soundFxAsset = '';
    expect(callProblem(f.params, lookup)).toBe('No sound FX picked');
    f.params.params.soundFxAsset = 'gone';
    expect(callProblem(f.params, lookup)).toBe('That sound FX is gone');
  });

  it('warns at Play sound when the parameters are for another FX', () => {
    expect(soundFxParamsMismatch(scene().play, scene().behavior.graph)).toBeNull();
    const f = scene({ other: true });
    expect(soundFxParamsMismatch(f.play, f.behavior.graph)).toBe('The parameters are for another sound FX');
  });

  it('follow a parameter renamed at the Input, edges and value included, and back on undo', () => {
    const f = scene({ pick: ['depth'], values: { depth: 7 } });
    f.stack.execute(new RenamePortCommand(f.fx.id, f.input.id, 'depth', 'drop'));
    expect(f.params.ports).toEqual([{ key: 'drop', kind: 'number' }]);
    expect(f.params.params.drop).toBe(7);
    const audio = fakeAudio();
    startWorld(f, { behaviors: true, audio }).frame();
    expect(audio.played[0]!.fx).toEqual({ pitch: 7, shifted: true, stages: [{ kind: 'gain', gain: 1 }] });
    f.stack.undo();
    expect(f.params.ports).toEqual([{ key: 'depth', kind: 'number' }]);
    expect(f.params.params.depth).toBe(7);
  });
});

describe('Set sound FX parameters (#315)', () => {
  /**
   * Pressing x plays Jump through an FX twice, the first `sound` – then hands `depth` to the voice
   * the first play gave out, over the length of that play where `spanned`.
   */
  function tuning(sound?: string, spanned = false) {
    const f = makeSpriteScene('Box');
    const { fx } = makeFx(f);
    const created = new CreateSoundCommand('Jump', FILE);
    f.stack.execute(created);
    const behavior = makeBehavior(f, 'Logic');
    place(f, behavior.id, { x: 0, y: 0 }, place(f, f.spriteId, { x: 0, y: 0 }));
    const edit = graphEditor(f, behavior);
    const first = edit.addNode('PlaySound', { sound: sound ?? created.asset.id, fx: fx.id });
    const second = edit.addNode('PlaySound', { sound: created.asset.id, fx: fx.id });
    const set = edit.addNode('SetSoundFxParameters');
    const params = edit.addNode('SoundFxParameters', { soundFxAsset: fx.id, depth: 3 });
    params.ports = [{ key: 'depth', kind: 'number' }];
    edit.wire([
      [edit.addNode('OnKeyDown', { key: 'x' }), 'exec', first, 'exec'],
      [first, 'exec', second, 'exec'],
      [second, 'exec', set, 'exec'],
      [first, 'voice', set, 'voice'],
      [params, 'params', set, 'fxParams'],
    ]);
    if (spanned) edit.wire([[first, 'length', set, 'time']]);
    return f;
  }

  it('hands the values to the one voice its Play sound gave out, not to another of the same sound', () => {
    const audio = fakeAudio();
    const { input, frame } = startWorld(tuning(), { behaviors: true, audio });
    input.press('x');
    frame();
    expect(audio.played).toHaveLength(2);
    expect(audio.tuned).toEqual([{ voice: 1, params: { depth: 3 } }]);
  });

  it('reaches nothing where its Play sound played nothing', () => {
    const audio = fakeAudio();
    const { input, frame } = startWorld(tuning('no-such-sound'), { behaviors: true, audio });
    input.press('x');
    frame();
    expect(audio.played).toHaveLength(1);
    expect(audio.tuned).toEqual([]);
  });

  it('spans a change over the length its Play sound hands out', () => {
    const audio = fakeAudio();
    const { input, frame } = startWorld(tuning(undefined, true), { behaviors: true, audio });
    input.press('x');
    frame();
    expect(audio.times).toEqual([0.25]);
  });
});