import "dart:collection";

String soundResult = "[key1];" "[key2];";

String test1(Object o) {}

String test2(Object o) => switch (o) {
      <String, int>{"key1": 1, "key2": 3} => "match-2",
      <String, int>{"key1": 1, "key2": 2} => "match-3",
      _ => "no match"
    };

String unsoundResult =
    "containsKey(key1);" "[key1];" "containsKey(key2);" "[key2];";

bool get hasUnsoundNullSafety => const <Null>[] is List<Object>;

class MyMap<K, V> extends MapBase<K, V> {
  @override
  Iterable<K> get keys {}
  Map<K, V> _inner;
  MyMap(this._inner);
  String log = "";
  @override
  bool containsKey(Object? key) {}
  @override
  int get length {}
  @override
  operator [](Object? key) {}
  @override
  remove(Object? key) {}
  @override
  void clear() {}
  void clearLog() {}
  @override
  void operator []=(key, value) {}
}

expect(expected, actual) {}

main() {}