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If you are not sure if you need tests, consider this rule of thumb: the purpose of a test is to make sure someone doesn't accidentally revert the fix. Ask yourself, is there anything in your PR that you feel it is important we not accidentally revert back to how it was before your fix?

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% ../../flutter_macos_3.10.1-stable/flutter/bin/flutter doctor -v

[!] Flutter (Channel stable, 3.10.1, on macOS 13.2.1 22D68 darwin-x64, locale zh-Hans-CN)
• Flutter version 3.10.1 on channel stable at /Users/zengjh/git/offical-flutter/flutter_macos_3.10.1-stable/flutter
! Warning: flutter on your path resolves to /Users/zengjh/git/hummers/hummer_2.5.1.7/src/flutter/uc/flutter_sdk/bin/flutter, which is not inside your current Flutter SDK checkout at
/Users/zengjh/git/offical-flutter/flutter_macos_3.10.1-stable/flutter. Consider adding /Users/zengjh/git/offical-flutter/flutter_macos_3.10.1-stable/flutter/bin to the front of your path.
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision d3d8effc68 (2 days ago), 2023-05-16 17:59:05 -0700
• Engine revision b4fb112
• Dart version 3.0.1
• DevTools version 2.23.1
• If those were intentional, you can disregard the above warnings; however it is recommended to use "git" directly to perform update checks and upgrades.

Here is the problem video 3.10 exists:

Here is the problem example:

apng-demo-toneyzeng.zip

after a more efficient solution