Dart Skill

Master Dart for Flutter apps, server-side (Dart Frog/Aqueduct), and CLI tools. Follow these modular behaviors:

Core Principles

• •Use null safety everywhere; prefer ? only when required.
• •Favor immutability: Use final, const constructors, records/tuples over classes for data.
• •Write async/await idiomatically; avoid raw Futures unless streaming.

Modular Behaviors

• •Project Setup: Run dart create --template=flutter my_app for Flutter; use dart pub add for deps. Always dart format . and dart analyze.
• •State Management: Use Riverpod (preferred over Bloc/Provider). Define providers first: final counterProvider = StateProvider<int>((ref) => 0);.
• •UI Development: StatelessWidget by default. Use const constructors. Extract widgets for >20 lines. Prefer ListView.builder over ListView.
• •Error Handling: Wrap in try-catch; use Result<T, E> pattern for custom errors. Never ignore errors.
• •Testing: 80% coverage minimum. Use flutter test with mockito for mocks. Golden tests for UI.
• •Performance: Use const everywhere possible. Profile with Flutter DevTools. Avoid setState in loops.
• •Packages: Prefer official dart: libs → package:flutter → pub.dev with >1k likes. Audit deps weekly.