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prefer-switch-expression

v1.26.0
style
dart 3.0+
configurable
pro+

Suggests converting switch statements to switch expressions.

In cases where all branches of a switch statement have a return statement or assign to the same variable, using a switch expression can make the code more compact and easier to understand.

⚙️ Config​

Set ignore-fallthrough-cases (default is false) to suggest converting to a switch expression even if there are cases with no body.

analysis_options.yaml
dart_code_metrics:
  rules:
    - prefer-switch-expression:
        ignore-fallthrough-cases: false

Example​

❌ Bad:

AssetSensorType convert(AssetSensorCategory sensorCategory) {
  // LINT: This switch statement can be converted to a switch expression.
  switch (sensorCategory) {
    case AssetSensorCategory.vibration:
      return AssetSensorType.first;
    case AssetSensorCategory.energy:
      return AssetSensorType.second;
  }
}

✅ Good:

AssetSensorType convert(AssetSensorCategory sensorCategory) {
  return switch (sensorCategory) {
    AssetSensorCategory.vibration => AssetSensorType.first,
    AssetSensorCategory.energy => AssetSensorType.second,
  };
}
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