class A {
  String get foo => "foo";
}
class B {
  int bar() => 42;
}
mixin M {
  void set callOnAssignment(void Function() f) {}
}
enum E1 with A { one, two }
enum E2 with A, B { one, two }
enum E3 with M { one, two }
expectEquals(x, y) {}
expectThrows(void Function() f) {}
void throwOnCall() {}
main() {}