Missing compile time check

main.dart

class Apple {}

class Banana {}

List<Apple> bag([List<Apple> apples]) => apples ?? <Banana>[];

void main() {
  // ok
  final bag1 = bag([Apple()]);
  print(bag1);
  
  // throws runtime error, should be compile time error 
  final bag2 = bag();
  print(bag2);
}