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prefer-sealed-bloc-state

added in: 1.24.0
warning
⚙️
Pro+

Warns when Bloc state classes do not have a sealed or final modifier.

info

If you keep your bloc state in separate files, consider using the include configuration option to scope the rule to only those files.

⚙️ Config​

Set name-pattern (default is State$) to set a regular expression pattern for bloc state.

analysis_options.yaml
dart_code_metrics:
  rules:
    - prefer-sealed-bloc-state:
        name-pattern: State$

Example​

❌ Bad:

// LINT: Prefer adding a 'sealed' or 'final' modifier to Bloc state.
abstract class CounterState {}

// LINT: Prefer adding a 'sealed' or 'final' modifier to Bloc state.
class CounterIncrementState extends CounterState {}

// LINT: Prefer adding a 'sealed' or 'final' modifier to Bloc state.
class CounterDecrementState extends CounterState {}

✅ Good:

sealed class CounterState {}

final class CounterIncrementState extends CounterState {}

final class CounterDecrementState extends CounterState {}