| // Copyright (c) 2013, 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. | 
 |  | 
 | import "package:expect/expect.dart"; | 
 | import "dart:collection"; | 
 |  | 
 | void main() { | 
 |   Set s = new HashSet(); | 
 |   s.add(1); | 
 |   Expect.equals("{1}", s.toString()); | 
 |   s.remove(1); | 
 |   s.add(s); | 
 |   Expect.equals("{{...}}", s.toString()); | 
 |  | 
 |   Queue q = new ListQueue(4); | 
 |   q.add(1); | 
 |   q.add(2); | 
 |   q.add(q); | 
 |   q.add(s); | 
 |  | 
 |   Expect.equals("{1, 2, {...}, {{...}}}", q.toString()); | 
 |  | 
 |   // Throwing in the middle of a toString does not leave the | 
 |   // set as being visited | 
 |   q.addLast(new ThrowOnToString()); | 
 |   Expect.throws(q.toString, (e) => e == "Bad!"); | 
 |   q.removeLast(); | 
 |   Expect.equals("{1, 2, {...}, {{...}}}", q.toString()); | 
 | } | 
 |  | 
 | class ThrowOnToString { | 
 |   String toString() { | 
 |     throw "Bad!"; | 
 |   } | 
 | } |