Error caused by Soundfile fetching order.

[FayCarsons]

Fetching soundfiles with a declare soundfiles directive, in an environment where fetches to / can return invalid data, throws an exception.

For example, this fails on the Cables.gl platform:

declare soundfiles "https://foo.com/bar";

file = soundfile("baz.wav", 2);

While this succeeds:

file = soundfile("https://foo.com/bar/baz.wav", 2);

In the case of Cables, what appears to be happening is that Cables responds to fetch(/baz.wav) with HTML as opposed to a 404. This causes FaustWASM to throw a "cannot decode audio data" exception. Changing the order the URLs are tried in, starting with the URL defined in the declare soundfiles directive as root, should solve this.

I would be happy to take this on but I may need some help determining which general part of the Soundfile or SoundfileReader class I would need to fix.

[sletz]

Probably in SoundfileReader like:

• https://github.com/grame-cncm/faustwasm/blob/master/src/SoundfileReader.ts#L8
• https://github.com/grame-cncm/faustwasm/blob/master/src/SoundfileReader.ts#L98