| name | flutter-dart-code-review |
| description | Library-agnostic Flutter/Dart code review checklist covering widget best practices, state management patterns, Dart idioms, performance, accessibility, security, and clean architecture. |
| origin | ECC |
Flutter/Dart Code Review Best Practices
Comprehensive, library-agnostic checklist for reviewing Flutter/Dart applications.
1. General Project Health
- Project follows consistent folder structure (feature-first or layer-first)
- Proper separation of concerns: UI, business logic, data layers
- No business logic in widgets; widgets are purely presentational
analysis_options.yaml includes a strict lint set with strict analyzer settings enabled
2. Dart Language Pitfalls
- Missing type annotations leading to
dynamic -- enable strict-casts, strict-inference, strict-raw-types
- Null safety misuse: Excessive
! (bang operator) instead of proper null checks
- Catching too broadly:
catch (e) without on clause
late overuse where nullable or constructor initialization would be safer- Prefer
final for locals and const for compile-time constants
- Use
package: imports for consistency
3. Widget Best Practices
- No single widget with a
build() method exceeding ~80-100 lines
const constructors used wherever possible- Colors from
Theme.of(context).colorScheme, not hardcoded values
- Text styles from
Theme.of(context).textTheme
- No network calls, file I/O, or heavy computation in
build()
4. State Management (Library-Agnostic)
- Business logic lives outside the widget layer
- State managers receive dependencies via injection
- Mutually exclusive states use sealed types, not boolean flags
- Every async operation models loading, success, and error as distinct states
- State consumer widgets scoped as narrow as possible
- All manual subscriptions cancelled in
dispose() / close()
5. Performance
const widgets used to stop rebuild propagationRepaintBoundary used around complex subtreesListView.builder used instead of ListView(children: [...]) for large lists- No sorting, filtering, or mapping large collections in
build()
6. Testing
- Unit tests cover all business logic
- Widget tests cover individual widget behavior
- Integration tests cover critical user flows
- Aim for 80%+ line coverage on business logic
- External dependencies are mocked or faked
7. Accessibility
Semantics widget used for screen reader labels- Tappable targets at least 48x48 pixels
- Color is not the sole indicator of state
- Text scales with system font size settings
8. Security
- Sensitive data stored using platform-secure storage
- API keys NOT hardcoded in Dart source
- HTTPS enforced for all API calls
- All user input validated before sending to API
9. Navigation and Routing
- One routing approach used consistently
- Route arguments are typed -- no
Map<String, dynamic> casting
- Auth guards/redirects centralized
- Deep links configured for both Android and iOS
10. Error Handling
FlutterError.onError overridden to capture framework errors- Error reporting service integrated
- API errors result in user-friendly error UI, not crashes
- Raw exceptions mapped to user-friendly messages before reaching the UI
