Simon Binder 4c3f603a41
Don't embed unreferenced assets (#179251)
When a Flutter app depends on a package using hooks to add code assets,
those get built to `build/native_assets/$platform`, where `$platform` is
something like `ios` or `macos`. Crucially, there's no difference
between simulator or release builds here, all native assets for a
platform end up in that directory.

To embed those frameworks with the app, the "sign and embed" stage of an
XCode build invokes `xcode_backend.dart`, which then copies all
frameworks from `build/native_assets/$targetPlatform` into
`$build/Runner.app/Frameworks`. This is a problem when a developer runs
a simulator build followed by a release build without clearing the build
folder in between, since both assets would be in
`build/native_assets/ios` at that point.

This fixes the issue by:

1. Reading the `native_assets.json` file emitted by the main build.
2. Only copying frameworks referenced in that file.

This still needs an integration test.

Closes https://github.com/flutter/flutter/issues/178602.

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---------

Co-authored-by: Victoria Ashworth <15619084+vashworth@users.noreply.github.com>
2026-01-06 10:40:38 +00:00
..