// Copyright (c) 2017, 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 abstract V operator [](Object key)
/// Returns the value for the given [key] or [null] if [key] is not in the map.
/// @description Checks that operator [] returns correct value for the given
/// [key].
/// @author iarkh@unipro.ru

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

main() {
  UnmodifiableMapBase base = new UnmodifiableMapBaseImpl(
      {1 : 1, 2 : 23, 37 : 49});
  Expect.equals(1, base[1]);
  Expect.equals(23, base[2]);
  Expect.equals(49, base[37]);
  Expect.isNull(base[0]);
  Expect.isNull(base[55]);
  Expect.isNull(base["test"]);
  Expect.isNull(base[null]);
}