221879 2021-02-14 14:37:54 -0800 Class not recognized in AudioWorklet when module is imported in two different ways 2024-03-05 12:08:16 -0800 1 1 1 Unclassified WebKit Web Audio Safari Technology Preview Mac (Intel) macOS 11 RESOLVED DUPLICATE 163209 InRadar P2 Minor --- 1 jeff.t.kaufman webkit-unassigned ashvayka cdumez ggaren jeff.t.kaufman mark.lam webkit-bug-importer ysuzuki oldest_to_newest 1729016 0 jeff.t.kaufman 2021-02-14 14:37:54 -0800 I have an AudioWorklet with: class AudioChunk { ... } function thaw_audio_chunk(o) { return new AudioChunk(...) } This is fine in Firefox and Chrome, but in Safari it throws: ReferenceError: Can't find variable: AudioChunk thaw_audio_chunk@https://www.jefftk.com/test/safari-audio-worklet-error2/audio-worklet.js:126:24 handle_message@https://www.jefftk.com/test/safari-audio-worklet-error2/audio-worklet.js:669:33 @https://www.jefftk.com/test/safari-audio-worklet-error2/audio-worklet.js:521:30 try_do@https://www.jefftk.com/test/safari-audio-worklet-error2/audio-worklet.js:544:15 @https://www.jefftk.com/test/safari-audio-worklet-error2/audio-worklet.js:520:20 Here is a standalone version that reproduces the bug reliably on my machine: https://www.jefftk.com/test/safari-audio-worklet-error2/ After pressing "start", giving mic permission, and waiting a few seconds you should see "This app has crashed. We're really sorry :-(" and that stack trace. Part of why it happens is that I am loading the worklet script two different ways: audio-worklet.js: if (typeof AudioWorkletProcessor === "undefined") { // do nothing } else { class AudioChunk { ... } ... } app.js import './audio-worklet.js'; ... await this.audioCtx.audioWorklet.addModule('audio-worklet.js'); ... This is a hack that I started doing because it got me better error messages in Chrome. Removing it is sufficient to stop triggering the bug in Safari: https://www.jefftk.com/test/safari-audio-worklet-error3/ Something else is also necessary to trigger it, however, because when I tried to make a very simple version that replicated this situation did not trigger it: https://www.jefftk.com/test/worklet-invoker This prints "success" in Firefox, Chrome, and Safari, and does not throw. This was easy to work around once I figured it out, since I can stop doing the silly load-it-both-ways thing, but I wanted to report it in case having the repro is useful. 1731997 1 webkit-bug-importer 2021-02-21 14:38:12 -0800 <rdar://problem/74575943> 2018842 2 ashvayka 2024-03-05 12:02:16 -0800 Please note that both ``` function thaw_audio_chunk(o) { return new AudioChunk(...) } ``` and the `class AudioChunk` it references are defined inside `else {` block, which subjects the function to have incorrect scope of the global environment. The root cause of it was broken Annex B function hoisting implementation, which was fixed in https://commits.webkit.org/268553@main *** This bug has been marked as a duplicate of bug 163209 *** 2018844 3 ashvayka 2024-03-05 12:08:16 -0800 (In reply to Jeff Kaufman from comment #0) > This was easy to work around once I figured it out, since I can stop doing > the silly load-it-both-ways thing, but I wanted to report it in case having > the repro is useful. Thank you Jeff for filing this bug along with easy-to-follow repro, that's highly appreciated!!