Some WebAudio signatures use number[] instead of Float32Array

[iccir]

TypeScript Version: 2.8.1

Search Terms: WebAudio, setValueCurveAtTime

Code

let context: AudioContext;

function demo(conext: AudioContext) {
    let gainNode = context.createGain();
    let sampleCount = Math.floor(0.25 * context.sampleRate);

    let values = new Float32Array(100);
    for (let i = 0; i < sampleCount; i++) {
        values[i] = i / sampleCount;
    }

    gainNode.gain.setValueCurveAtTime(values, 0, sampleCount / context.sampleRate);
}

Expected behavior:
GainNode's first parameter should be a Float32Array per the WebAudio specification. TypeScript's lib.d.ts file thinks it's a number[]. The above code shouldn't warn.

Actual behavior:
Argument of type 'Float32Array' is not assignable to parameter of type 'number[]'

Playground Link: http://www.typescriptlang.org/play/#src=%2F%2F%20WebAudio%20setValueCurveAtTime%20issue%0D%0A%0D%0Alet%20context%3A%20AudioContext%3B%0D%0A%0D%0Afunction%20demo(conext%3A%20AudioContext)%20%7B%0D%0A%20%20%20%20let%20gainNode%20%3D%20context.createGain()%3B%0D%0A%20%20%20%20let%20sampleCount%20%3D%20Math.floor(0.25%20*%20context.sampleRate)%3B%0D%0A%0D%0A%20%20%20%20let%20values%20%3D%20new%20Float32Array(100)%3B%0D%0A%20%20%20%20for%20(let%20i%20%3D%200%3B%20i%20%3C%20sampleCount%3B%20i%2B%2B)%20%7B%0D%0A%20%20%20%20%20%20%20%20values%5Bi%5D%20%3D%20i%20%2F%20sampleCount%3B%0D%0A%20%20%20%20%7D%0D%0A%0D%0A%20%20%20%20gainNode.gain.setValueCurveAtTime(values%2C%200%2C%20sampleCount%20%2F%20context.sampleRate)%3B%0D%0A%7D%0D%0A

Related Issues:

[iccir]

Additionally, I believe that the following signatures use number[] instead of the correct Float32Array:

interface WaveShaperOptions extends AudioNodeOptions {
    curve?: number[];
    oversample?: OverSampleType;
}

interface PeriodicWaveOptions extends PeriodicWaveConstraints {
    imag?: number[];
    real?: number[];
}

However, I'm not able to figure out why PeriodicWaveOptions extends PeriodicWaveConstraints or how AudioNodeOptions is ever used.

[iccir]

I explored making a PR. However, this signature comes from browser.webidl.preprocessed.json in TSJS-lib-generator, so it's possibly an Edge issue.

[mhegazy]

We have mechanisms to override types from the widl file. Look at microsoft/TypeScript-DOM-lib-generator#404 as a reference.

[mhegazy]

PRs welcomed. You can find more information about contributing lib.d.ts fixes at https://github.com/Microsoft/TypeScript/blob/master/CONTRIBUTING.md#contributing-libdts-fixes.

[iccir]

Thanks! I fixed it for setValueCurveAtTime. I held off on changing PeriodicWaveOptions/AudioNodeOptions as I couldn't figure out how they are used.