Both dart test and flutter test support a --run-skipped, which is intended to mean "run tests otherwise that would be skipped". Ideally it would be used to temporarily (either locally or on a bringup: true task) run tests that are flaking or failing for reasons that we don't want to affect the mainline tree or development experience.

For example:

cd flutter/packages/flutter_tools
dart test test/general.shard --run-skipped

However, sometimes we use skip to mean the test can't run in this configuration, such as:

test('...', () {
  // ...
}, skip: !Platform.isWindows ? 'Test only runs on windows' : false);

In that case, --run-skipped not only can never work, but now the feature cannot be used across the codebase.

For Dart (dart test-instrumented) tests, we could use @TestOn instead:

@TestOn('windows')
library;

// ...

void main() {
  test('...', () {
  
  });
}

However, my understanding is this feature does not work in flutter test, so it would not work everywhere/we would diverge.

It would be awesome to have some instruction, outside of commenting code in/out, how we could run skipped tests but also not run tests that are never intended to run in a given configuration or platform. Ideally (to me) that would mean using --run-skipped and perhaps using/supporting @TestOn broadly, but that is obviously more work.