avoid-wildcard-cases-with-sealed-classes

v1.31.0

warning

effort: 6m

dart 3.0+

teams+

Warns when a switch on a sealed class has a wildcard pattern case.

Once the sealed class has a new subclass, the analyzer will highlight all cases where this new subclass should be used, unless there is a wildcard case.

Example

❌ Bad:

void someFn(Vehicle value) {
  final result = switch (value) {
    Car() => 1,
    // LINT: Avoid wildcard cases with sealed classes.
    //  Try enumerating all the possible values of the switch expression.
    _ => 2,
  };
}

sealed class Vehicle {}

class Car extends Vehicle {}

class Truck extends Vehicle {}

✅ Good:

void someFn(Vehicle value) {
  final result = switch (value) {
    Car() => 1,
    Truck() => 2,
  };
}

sealed class Vehicle {}

class Car extends Vehicle {}

class Truck extends Vehicle {}

Related Rules

• avoid-wildcard-cases-with-enums
• prefer-wildcard-pattern
• avoid-keywords-in-wildcard-pattern