Error with just_audio_web

[maknon]

Which API doesn't behave as documented, and how does it misbehave?
Start getting errors while building web version of my app

Minimal reproduction project
The example

To Reproduce (i.e. user steps, not code)
Build the web version of the example in:
https://github.com/ryanheise/just_audio/blob/minor/just_audio/example/lib/main.dart

Error messages

Compiling lib\main.dart for the Web...                             10.4s
Target dart2js failed: ProcessException: Process exited abnormally with exit code 1:
../../AppData/Local/Pub/Cache/hosted/pub.dev/just_audio_web-0.4.12/lib/just_audio_web.dart:120:11:
Error: Function converted via 'toJS' contains invalid types in its function signature: 'Null Function(*dynamic*)'.
        }.toJS);
          ^
../../AppData/Local/Pub/Cache/hosted/pub.dev/just_audio_web-0.4.12/lib/just_audio_web.dart:125:11:
Error: Function converted via 'toJS' contains invalid types in its function signature: 'Null Function(*dynamic*)'.
        }.toJS);
          ^
../../AppData/Local/Pub/Cache/hosted/pub.dev/just_audio_web-0.4.12/lib/just_audio_web.dart:130:11:
Error: Function converted via 'toJS' contains invalid types in its function signature: '*Future<Null>* Function(*dynamic*)'.
        }.toJS);
          ^
../../AppData/Local/Pub/Cache/hosted/pub.dev/just_audio_web-0.4.12/lib/just_audio_web.dart:136:11:
Error: Function converted via 'toJS' contains invalid types in its function signature: 'Null Function(*dynamic*)'.
        }.toJS);
          ^
../../AppData/Local/Pub/Cache/hosted/pub.dev/just_audio_web-0.4.12/lib/just_audio_web.dart:141:11:
Error: Function converted via 'toJS' contains invalid types in its function signature: 'Null Function(*dynamic*)'.
        }.toJS);
          ^
../../AppData/Local/Pub/Cache/hosted/pub.dev/just_audio_web-0.4.12/lib/just_audio_web.dart:146:11:
Error: Function converted via 'toJS' contains invalid types in its function signature: 'Null Function(*dynamic*)'.
        }.toJS);
          ^
../../AppData/Local/Pub/Cache/hosted/pub.dev/just_audio_web-0.4.12/lib/just_audio_web.dart:151:11:
Error: Function converted via 'toJS' contains invalid types in its function signature: 'Null Function(*dynamic*)'.
        }.toJS);
          ^
../../AppData/Local/Pub/Cache/hosted/pub.dev/just_audio_web-0.4.12/lib/just_audio_web.dart:157:11:
Error: Function converted via 'toJS' contains invalid types in its function signature: 'Null Function(*dynamic*)'.
        }.toJS);
          ^
../../AppData/Local/Pub/Cache/hosted/pub.dev/just_audio_web-0.4.12/lib/just_audio_web.dart:162:11:
Error: Function converted via 'toJS' contains invalid types in its function signature: 'Null Function(*dynamic*)'.
        }.toJS);
          ^
Error: Compilation failed.
  Command: E:\Support\flutter\bin\cache\dart-sdk\bin\dart.exe E:\Support\flutter\bin\cache\dart-sdk\bin\snapshots\dart2js.dart.snapshot --platform-binaries=E:\Support\flutter\bin\cache\flutter_web_sdk\kernel --invoker=flutter_tool -Ddart.vm.product=true -DFLUTTER_WEB_AUTO_DETECT=false -DFLUTTER_WEB_USE_SKIA=true -DFLUTTER_WEB_CANVASKIT_URL=https://www.gstatic.com/flutter-canvaskit/059e4e6d8ff6de39c29441c53e949bfb0bf17972/ --native-null-assertions --no-source-maps -o C:\Users\ias12\Desktop\untitled\.dart_tool\flutter_build\a4603cca5b796a7858700a1b566311b4\app.dill --packages=C:\Users\ias12\Desktop\untitled\.dart_tool\package_config.json --cfe-only C:\Users\ias12\Desktop\untitled\.dart_tool\flutter_build\a4603cca5b796a7858700a1b566311b4\main.dart
#0      RunResult.throwException (package:flutter_tools/src/base/process.dart:122:5)
#1      _DefaultProcessUtils.run (package:flutter_tools/src/base/process.dart:389:19)
<asynchronous suspension>
#2      Dart2JSTarget.build (package:flutter_tools/src/build_system/targets/web.dart:202:5)
<asynchronous suspension>
#3      _BuildInstance._invokeInternal (package:flutter_tools/src/build_system/build_system.dart:891:9)
<asynchronous suspension>
#4      Future.wait.<anonymous closure> (dart:async/future.dart:520:21)
<asynchronous suspension>
#5      _BuildInstance.invokeTarget (package:flutter_tools/src/build_system/build_system.dart:829:32)
<asynchronous suspension>
#6      Future.wait.<anonymous closure> (dart:async/future.dart:520:21)
<asynchronous suspension>
#7      _BuildInstance.invokeTarget (package:flutter_tools/src/build_system/build_system.dart:829:32)
<asynchronous suspension>
#8      FlutterBuildSystem.build (package:flutter_tools/src/build_system/build_system.dart:651:16)
<asynchronous suspension>
#9      WebBuilder.buildWeb (package:flutter_tools/src/web/compile.dart:92:34)
<asynchronous suspension>
#10     BuildWebCommand.runCommand (package:flutter_tools/src/commands/build_web.dart:230:5)
<asynchronous suspension>
#11     FlutterCommand.run.<anonymous closure> (package:flutter_tools/src/runner/flutter_command.dart:1450:27)
<asynchronous suspension>
#12     AppContext.run.<anonymous closure> (package:flutter_tools/src/base/context.dart:153:19)
<asynchronous suspension>
#13     CommandRunner.runCommand (package:args/command_runner.dart:212:13)
<asynchronous suspension>
#14     FlutterCommandRunner.runCommand.<anonymous closure> (package:flutter_tools/src/runner/flutter_command_runner.dart:421:9)
<asynchronous suspension>
#15     AppContext.run.<anonymous closure> (package:flutter_tools/src/base/context.dart:153:19)
<asynchronous suspension>
#16     FlutterCommandRunner.runCommand (package:flutter_tools/src/runner/flutter_command_runner.dart:364:5)
<asynchronous suspension>
#17     run.<anonymous closure>.<anonymous closure> (package:flutter_tools/runner.dart:130:9)
<asynchronous suspension>
#18     AppContext.run.<anonymous closure> (package:flutter_tools/src/base/context.dart:153:19)
<asynchronous suspension>
#19     main (package:flutter_tools/executable.dart:94:3)
<asynchronous suspension>

Error: Failed to compile application for the Web.

Expected behavior
compiling without errors

Screenshots
NA

Desktop (please complete the following information):

• OS: Win 11
• Browser: Edge latest

Smartphone (please complete the following information):
NA

Flutter SDK version

[√] Flutter (Channel beta, 3.26.0-0.1.pre, on Microsoft Windows [Version 10.0.22631.4169], locale en-US)
    • Flutter version 3.26.0-0.1.pre on channel beta at E:\Support\flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision ee624bc4fd (2 days ago), 2024-09-10 17:41:06 -0500
    • Engine revision 059e4e6d8f
    • Dart version 3.6.0 (build 3.6.0-216.1.beta)
    • DevTools version 2.39.0

[√] Windows Version (Installed version of Windows is version 10 or higher)

[√] Android toolchain - develop for Android devices (Android SDK version 35.0.0)
    • Android SDK at C:\Users\ias12\AppData\Local\Android\sdk
    • Platform android-35, build-tools 35.0.0
    • Java binary at: C:\Users\ias12\AppData\Local\Programs\Android Studio\jbr\bin\java
    • Java version OpenJDK Runtime Environment (build 21.0.3+-12282718-b509.11)
    • All Android licenses accepted.

[X] Chrome - develop for the web (Cannot find Chrome executable at .\Google\Chrome\Application\chrome.exe)
    ! Cannot find Chrome. Try setting CHROME_EXECUTABLE to a Chrome executable.

[√] Visual Studio - develop Windows apps (Visual Studio Community 2022 17.11.3)
    • Visual Studio at C:\Program Files\Microsoft Visual Studio\2022\Community
    • Visual Studio Community 2022 version 17.11.35303.130
    • Windows 10 SDK version 10.0.22621.0

[√] Android Studio (version 2024.2)
    • Android Studio at C:\Users\ias12\AppData\Local\Programs\Android Studio
    • Flutter plugin can be installed from:
       https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
       https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 21.0.3+-12282718-b509.11)

[√] IntelliJ IDEA Community Edition (version 2024.3)
    • IntelliJ at C:\Users\ias12\AppData\Local\Programs\IntelliJ IDEA Community Edition
    • Flutter plugin version 81.1.3
    • Dart plugin version 243.12818.47

[√] Connected device (2 available)
    • Windows (desktop) • windows • windows-x64    • Microsoft Windows [Version 10.0.22631.4169]
    • Edge (web)        • edge    • web-javascript • Microsoft Edge 128.0.2739.67

[√] Network resources
    • All expected network resources are available.

! Doctor found issues in 1 category.

Additional context
it was working at one point of time but not sure which update break all of this

[mikefaille]

I can reproduce this problem switching from :

    • Flutter version 3.24.3 on channel stable at /opt/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 2663184aa7 (7 days ago), 2024-09-11 16:27:48 -0500
    • Engine revision 36335019a8
    • Dart version 3.5.3
    • DevTools version 2.37.3

to

    • Flutter version 3.26.0-0.1.pre on channel beta at /opt/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision ee624bc4fd (7 days ago), 2024-09-10 17:41:06 -0500
    • Engine revision 059e4e6d8f
    • Dart version 3.6.0 (build 3.6.0-216.1.beta)
    • DevTools version 2.39.0

using :
flutter_widget_from_html: ^0.15.2

[ryanheise]

I don't use the beta version of Flutter, but I would guess it may help to add explicit type annotations to parts of the plugin that look like this:

        (event) {
          _durationCompleter?.completeError(_audioElement.error!);
        }.toJS);

So replacing (event) by (Event event). I wouldn't be able to test it for you, though. Would anyone like to try this on their end?

[SleepySquash]

@ryanheise,

Would anyone like to try this on their end?

This fixes the issue on my end. Also ended event listener callback is marked async, which should be replaced with a sync function (there's nothing async going on inside it after all):

_audioElement.addEventListener(
    'ended',
    (Event event) {
      _currentAudioSourcePlayer?.complete();
    }.toJS);

[ryanheise]

Thanks for testing that. Would you be interested in contributing that change as a pull request, or would you prefer me to replicate that change?

[SleepySquash]

@ryanheise, sorry for a delayed response - yep, sure, no problem! I've opened and prepared a PR: #1329
If there's anything else I should do with the PR, please, let me know.

[SergeBerwert]

I experience the same issue but only on the build server and not on the local machine. I have no idea why. Both have the same flutter/dart version.