Error: The class 'FileSystemEvent' can't be extended, implemented, or mixed in outside of its library because it's a sealed class.

[SonPham17]

I upgrade flutter version 3.13. When I put new value in arb file, plugin generate error with message:

Failed to build intl_utils:generate: ../../.pub-cache/hosted/pub.dev/watcher-1.0.2/lib/src/constructable_file_system_event.dart:7:57: Error: The class 'FileSystemEvent' can't be extended, implemented, or mixed in outside of its library because it's a sealed class. abstract class _ConstructableFileSystemEvent implements FileSystemEvent { ^ Process finished with exit code 1

Please help me check issue, many thanks 😊

Flutter doctor

[✓] Flutter (Channel stable, 3.13.0, on macOS 13.4.1 22F770820d darwin-x64, locale en-VN) • Flutter version 3.13.0 on channel stable at /Users/sonpham/Dev/flutter_version/flutter • Upstream repository https://github.com/flutter/flutter.git • Framework revision efbf63d9c6 (7 days ago), 2023-08-15 21:05:06 -0500 • Engine revision 1ac611c64e • Dart version 3.1.0 • DevTools version 2.25.0 [✓] Android toolchain - develop for Android devices (Android SDK version 33.0.1) • Android SDK at /Users/sonpham/Library/Android/sdk • Platform android-33, build-tools 33.0.1 • ANDROID_HOME = /Users/sonpham/Library/Android/sdk • Java binary at: /Applications/Android Studio.app/Contents/jbr/Contents/Home/bin/java • Java version OpenJDK Runtime Environment (build 17.0.6+0-17.0.6b829.9-10027231) • All Android licenses accepted. [✓] Xcode - develop for iOS and macOS (Xcode 14.3.1) • Xcode at /Applications/Xcode.app/Contents/Developer • Build 14E300c • CocoaPods version 1.12.1 [✓] Chrome - develop for the web • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome [✓] Android Studio (version 2022.3) • Android Studio at /Applications/Android Studio.app/Contents • 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 17.0.6+0-17.0.6b829.9-10027231) [✓] VS Code (version 1.81.1) • VS Code at /Applications/Visual Studio Code.app/Contents • Flutter extension can be installed from: 🔨 https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter [✓] Connected device (3 available) • sdk gphone64 x86 64 (mobile) • emulator-5554 • android-x64 • Android 13 (API 33) (emulator) • macOS (desktop) • macos • darwin-x64 • macOS 13.4.1 22F770820d darwin-x64 • Chrome (web) • chrome • web-javascript • Google Chrome 116.0.5845.96 [✓] Network resources • All expected network resources are available. • No issues found!

[lzoran]

Hi @SonPham17,

I believe that this problem is somehow related to an issue with the cache that occurs after a Flutter upgrade.

What version of the intl_utils package do you use?

flutter pub global list

Could you check if reactivating the intl_utils package helps?

flutter pub global deactivate intl_utils
flutter pub global activate intl_utils

[SonPham17]

flutter pub global deactivate intl_utils flutter pub global activate intl_utils

It worked for me! Thank you 🙏