// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

// @dart = 2.9

/// @assertion SplayTreeMap([int compare(K key1, K key2),
/// bool isValidKey(potentialKey)])
/// ...
/// If the map contains only the key [a], then [map.containsKey(b)] will return
/// [true] if and only if [compare(a, b) == 0], and the value of [a == b] is not
/// even checked.
/// @description Checks that if [compare(a, b) == 0] then [map.containsKey(b)]
/// returns [true]
/// @author sgrekhov@unipro.ru

import "dart:collection";
import "../../../Utils/expect.dart";

class C {
  int value;
  C(this.value);
}

int compare(var key1, var key2) {
  return key1.value - key2.value;
}

main() {
  SplayTreeMap map = new SplayTreeMap(compare);
  C c1 = new C(1);
  C c2 = new C(1);

  map[c1] = 1;
  Expect.isTrue(map.containsKey(c2));
}