// 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.

/// @assertion void retainAll(Iterable<Object> elements)
/// Removes all elements of this set that are not elements in [elements].
///
/// Checks for each element of elements whether there is an element in this set
/// that is equal to it (according to this.contains), and if so, the equal
/// element in this set is retained, and elements that are not equal to any
/// element in elements are removed.
/// @description Checks that retainAll() removes all elements of this set that
/// are not elements in [elements]
/// @author sgrekhov@unipro.ru

library retainAll_A01_t01;
import "set.lib.dart";
import "../../../Utils/expect.dart";

test(Set create([Set content])) {
  Set set = create();

  set.retainAll([].toSet());
  Expect.equals(0, set.length);

  set.retainAll([1, 2, 3].toSet());
  Expect.equals(0, set.length);

  set.addAll([1, 2, 3, 4, 5, 6, 7]);

  set.retainAll([1, 2, 3].toSet());
  Expect.equals(3, set.length);
  Expect.isTrue(set.containsAll([1, 2, 3]));
}

main() {
  test(create);
}