Rule Catalog

Falcon includes 58+ lint rules organized into 6 categories. These rules help you catch bugs, enforce best practices, and improve code quality across your Flutter and Dart projects.

Common Rules

31 rules covering general Dart best practices, type safety, and code style.

Flutter Rules

11 rules specific to Flutter widget lifecycle, performance, and accessibility.

Code Examples

avoid-empty-catch

Empty catch blocks silently swallow exceptions, making debugging difficult. Always handle or rethrow errors.

try {
  await fetchData();
} catch (e) {
  // empty — error is silently ignored
}

try {
  await fetchData();
} catch (e, stackTrace) {
  logError(e, stackTrace);
  rethrow;
}

ensure-dispose-lifecycle

Controllers and subscriptions must be disposed to prevent memory leaks. Override dispose() and clean up resources.

class MyWidget extends StatefulWidget {
  final TextEditingController controller =
      TextEditingController();
  // Missing dispose — controller leaks
}

class MyWidget extends StatefulWidget {
  final TextEditingController controller =
      TextEditingController();

  @override
  void dispose() {
    controller.dispose();
    super.dispose();
  }
}

avoid-unawaited-futures

Futures must be awaited to handle errors and ensure proper execution order. Unawaited futures can cause unhandled exceptions.

void saveData() {
  writeToFile(data);  // Future not awaited — errors lost
}

Future<void> saveData() async {
  await writeToFile(data);
}

BLoC Rules

5 rules for projects using the BLoC pattern for state management.

Provider / Riverpod Rules

5 rules for projects using Provider or Riverpod for dependency injection and state management.

Equatable Rules

3 rules for projects using Equatable for value equality.

Presets

Presets bundle related rules for quick configuration. Choose a preset that matches your project's dependencies.