LibTest/collection/LinkedHashMap/LinkedHashMap.fromIterable_A04_t01.dart

// 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 LinkedHashMap.fromIterable(Iterable iterable,
/// {K key(element), V value(element)})
/// ...
/// If no values are specified for [key] and [value] the default is the identity
/// function
/// @description Checks that if no values are specified for key and value the
/// default is the identity function
/// @author sgrekhov@unipro.ru

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

check(Iterable it, Iterable expected) {
  LinkedHashMap m = new LinkedHashMap.fromIterable(it);
  Expect.equals(expected.length, m.length);
  for (var v in expected) {
    Expect.equals(v, m[v]);
  }
}

class C {}

main() {
  var o1 = new Object();
  var o2 = new Object();
  C c1 = new C();
  C c2 = new C();

  check([o1, o2, c1, c2], [o1, o2, c1, c2]);
  check([null, null], [null]);
}