Disclaimer

This is a relatively old package, which wasn't maintained for several years. We've forked it so that we have the ability to update bits of it that are no longer compliant with the Web Audio API.

web-audio-test-api


> Web Audio API test library for CI

Installation

$3

``
$ npm install --save-dev web-audio-test-api
`

Install Web Audio API interfaces to global scope

`javascript
import "web-audio-test-api";
`

$3

- web-audio-test-api.js

Replace existing Web Audio API with web-audio-test-api

`html

`

if you won't use web-audio-test-api

`javascript
WebAudioTestAPI.unuse();
`

Online Test Suite

- web-audio-test-api.js - online test suite

Documents

- Web Audio API Specification
- Test API Reference

Features

- Strict type check more than original Web Audio API

`javascript
var audioContext = new AudioContext();
var osc = audioContext.createOsillator();

// correct
osc.frequency.value = 880;

// wrong
assert.throws(function() {
osc.frequency = 880;
}, function(e) {
return e instanceof TypeError &&
e.message === "OscillatorNode#frequency is readonly";
});

assert.throws(function() {
osc.type = 2;
}, function(e) {
return e instanceof TypeError &&
e.message === "OscillatorNode#type should be an enum { sine, square, sawtooth, triangle }, but got: 2";
});
});
`

- Convert to JSON from audio graph

`javascript
var audioContext = new AudioContext();
var osc = audioContext.createOscillator();
var lfo = audioContext.createOscillator();
var amp = audioContext.createGain();

lfo.$id = "LFO"; // name for debugging

osc.type = "sawtooth";
osc.frequency.value = 880;

lfo.frequency.value = 2;

lfo.connect(amp.gain);
osc.connect(amp);
amp.connect(audioContext.destination);

assert.deepEqual(audioContext.toJSON(), {
name: "AudioDestinationNode" // +------------------+
inputs: [ // | OscillatorNode |
{ // | - type: sawtooth |
name: "GainNode", // | - frequency: 220 |
gain: { // | - detune: 0 |
value: 1, // +------------------+
inputs: [ // |
{ // +-----------+ +--------------------+
name: "OscillatorNode#LFO", // | GainNode | | OscillatorNode#LFO |
type: "sine", // | - gain: 1 |--| - frequency: 2 |
frequency: { // +-----------+ | - detune: 0 |
value: 2, // | +--------------------+
inputs: [] // |
}, // +----------------------+
detune: { // | AudioDestinationNode |
value: 0, // +----------------------+
inputs: []
},
inputs: []
}
]
},
inputs: [
{
name: "OscillatorNode",
type: "sawtooth",
frequency: {
value: 880,
inputs: []
},
detune: {
value: 0,
inputs: []
},
inputs: []
}
]
}
]
});
`

- OscillatorNode/BufferSourceNode state

`javascript
var audioContext = new AudioContext();
var node = audioContext.createOscillator();

assert(node.$state === "UNSCHEDULED");

node.start(0.100);
node.stop(0.150);
node.connect(audioContext.destination);

audioContext.$processTo("00:00.000");
assert(node.$state === "SCHEDULED", "00:00.000");

audioContext.$processTo("00:00.099");
assert(node.$state === "SCHEDULED", "00:00.099");

audioContext.$processTo("00:00.100");
assert(node.$state === "PLAYING", "00:00.100");

audioContext.$processTo("00:00.149");
assert(node.$state === "PLAYING", "00:00.149");

audioContext.$processTo("00:00.150");
assert(node.$state === "FINISHED", "00:00.150");

// other way
assert(node.$stateAtTime("00:00.000") === "SCHEDULED");
assert(node.$stateAtTime("00:00.099") === "SCHEDULED");
assert(node.$stateAtTime("00:00.100") === "PLAYING");
assert(node.$stateAtTime("00:00.149") === "PLAYING");
assert(node.$stateAtTime("00:00.150") === "FINISHED");
`

- AudioParam simulation

`javascript
var audioContext = new AudioContext();
var node = audioContext.createOscillator();

node.frequency.setValueAtTime(880, 0.500);
node.frequency.linearRampToValueAtTime(440, 1.500);
node.connect(audioContext.destination);

audioContext.$processTo("00:00.000");
assert(node.frequency.value === 440, "00:00.000");

audioContext.$processTo("00:00.250");
assert(node.frequency.value === 440, "00:00.250");

audioContext.$processTo("00:00.500");
assert(node.frequency.value === 880, "00:00.500"); // <- setValueAtTime
// ^
audioContext.$processTo("00:00.750"); // |
assert(node.frequency.value === 770, "00:00.750"); // |
// |
audioContext.$processTo("00:01.000"); // |
assert(node.frequency.value === 660, "00:01.000"); // | linearRampToValueAtTime
// |
audioContext.$processTo("00:01.250"); // |
assert(node.frequency.value === 550, "00:01.250"); // |
// |
audioContext.$processTo("00:01.500"); // v
assert(node.frequency.value === 440, "00:01.500"); //

audioContext.$processTo("00:01.750");
assert(node.frequency.value === 440, "00:01.750");

// other way
assert(node.frequency.$valueAtTime("00:00.000" === 440);
assert(node.frequency.$valueAtTime("00:00.250" === 440);
assert(node.frequency.$valueAtTime("00:00.500" === 880); // <- setValueAtTime
assert(node.frequency.$valueAtTime("00:00.750" === 770); // ^
assert(node.frequency.$valueAtTime("00:01.000" === 660); // | linearRampToValueAtTime
assert(node.frequency.$valueAtTime("00:01.250" === 550); // v
assert(node.frequency.$valueAtTime("00:01.500" === 440); //
assert(node.frequency.$valueAtTime("00:01.750" === 440);
`

- ScriptProcessing simulation

`javascript
var audioContext = new AudioContext();
var node = audioContext.createScriptProcessor(1024, 2, 2);

node.onaudioprocess = sinon.spy();
node.connect(audioContext.destination);

audioContext.$processTo("00:00.500");
assert(node.onaudioprocess.callCount === 22);
// 22times call (0.5 / (1024 / 44100) = 21.5332)
`

- DecodeAudioData simulation

`javascript
var audioContext = new AudioContext();

// audioContext.DECODE_AUDIO_DATA_RESULT = customResult;
// audioContext.DECODE_AUDIO_DATA_FAILED = true;

audioContext.decodeAudioData(audioData, function(result) {
// successCallback
assert(result instanceof AudioBuffer);
}, function() {
// errorCallback
throw new ERROR("NOT REACHED");
});
`

- New API support

`javascript
WebAudioTestAPI.setState({
"AudioContext#createStereoPanner": "enabled",
});

var audioContext = new AudioContext();

var node = audioContext.createStereoPanner();

console.log(WebAudioTestAPI.getState("AudioContext#createStereoPanner")); // "enabled"
`

| API Name | states |
|---------------------------------------|------------------------------|
| AnalyserNode#getFloatTimeDomainData | "enabled" or "disabled" |
| AudioBuffer#copyToChannel | "enabled" or "disabled" |
| AudioBuffer#copyFromChannel | "enabled" or "disabled" |
| AudioContext#createAudioWorker | "disabled" |
| AudioContext#createStereoPanner | "enabled" or "disabled" |
| AudioContext#close | "enabled" or "disabled" |
| AudioContext#suspend | "enabled" or "disabled" |
| AudioContext#resume | "enabled" or "disabled" |
| AudioContext#decodeAudioData | "promise" or "void" |
| OfflineAudioContext#startRendering | "promise" or "void" |
| AudioNode#disconnect` | "selective" or "channel" |

License

web-audio-test-api.js is available under the The MIT License.