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prefer-switch-with-sealed-classes

v1.17.0
style
effort: 6m
teams+

Suggests to use a switch statement or expression instead of conditionals with sealed class instances.

When it comes to sealed classes, the analyzer warns you when a new class is not covered by a switch case. This feature is not available for if statements and conditional expressions. Therefore using switches where possible can reduce the number of potential bugs.

Example​

❌ Bad:

void fn() {
  final Vehicle? value;

  // LINT: Prefer switch statement/expression when checking sealed classes.
  if (value is Car || value is Truck) {}

  // LINT: Prefer switch statement/expression when checking sealed classes.
  if (value case Car() || Truck()) {}
}

sealed class Vehicle {}

class Car extends Vehicle {}

class Truck implements Vehicle {
  const Truck();
}

✅ Good:

void fn() {
  final Vehicle? value;

  switch (value) {
    case Car():
      ...

    case Truck():
     ...
  }
}
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