| name | dart-best-practices |
| description | Dart code quality conventions: naming, const/final/var hierarchy, single quotes, trailing commas, collection idioms, tear-offs, and import organization. Use when writing new Dart code or reviewing for style violations — wrong import style, global variables, var misuse, anonymous lambdas where tear-offs fit, or missing trailing commas. (triggers: **/*.dart, naming, convention, trailing comma, import, tear-off) |
Dart Best Practices
Priority: P1 (OPERATIONAL)
Best practices for writing clean, maintainable Dart code.
- Scoping:
- No global variables.
- Private globals (if required) must start with
_.
- Immutability: Use
const > final > var.
- Config: Use
--dart-define for secrets. Never hardcode API keys.
- Naming: Follow effective-dart (PascalCase classes, camelCase members).
- Strings: Prefer single quotes; use double quotes only for interpolation needs.
- Trailing Commas: Always use trailing commas for multi-line literals/params.
- Expression Bodies: Prefer
=> for single-expression functions/getters.
- Collections:
- Use
.map, .where, .fold, .any over manual loops when clarity improves.
- Type empty collections (
<String>[], <String, User>{}) to avoid dynamic.
- Use collection
if/for and spread operators for composable lists/maps.
- Async: Always
await futures unless intentionally fire-and-forget.
import 'models/user.dart'; // Good
import 'package:app/models/user.dart'; // Avoid local absolute
Anti-Patterns
- ❌
var result = fetchOrders() — use final or an explicit type; var only for locally obvious types in short scopes
- ❌
import 'package:myapp/features/orders/order_model.dart' within the same package — use relative imports for intra-package files
- ❌ Top-level mutable
List<Order> cachedOrders = [] — no global mutable state; use DI or encapsulate in a class
- ❌
list.forEach((item) => doSomething(item)) — prefer tear-offs: list.forEach(doSomething)
