because it was totally possible to opt-out of synthetic packages (i.e. in a l10n.yaml file), but still not be specifying flutter: generate:, which I believe is supposed to still be an error.

Not sure I follow. If you opt out of synthetic package for gen-l10n, then it would generate into your source directory. Not specifying generate wouldn't be an error then?

@jonahwilliams::

Not specifying generate wouldn't be an error then?

The presence of (https://docs.flutter.dev/tools/pubspec):

# pubspec.yaml
flutter:
  generate: true

... means enables generation of localized strings from arb files.

It is not directly connected to package:flutter_gen (maybe it was at inception?), in fact post migration (https://docs.flutter.dev/release/breaking-changes/flutter-generate-i10n-source#migration-guide) you'll still keep those lines, the difference is that synthetic-package: false becomes the default (instead of true).

oh.... interesting...

😓

Apparently we have tests that relied on the behavior of this error never showing up 🤦🏼

Updated! It was just 2 call sites, I might have slightly over-exagerrated.

autosubmit label was removed for flutter/flutter/163145, because - The status or check suite Google testing has failed. Please fix the issues identified (or deflake) before re-applying this label.