|  | // Copyright (c) 2011, 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 completeError(Object exception, [Object stackTrace]) | 
|  | /// Calling complete or completeError must not be done more than once. | 
|  | /// @description Checks that an error is thrown if | 
|  | /// the completer is already completed with a value. | 
|  | /// @author msyabro | 
|  |  | 
|  | import "../../../Utils/expect.dart"; | 
|  | import "dart:async"; | 
|  |  | 
|  | main() { | 
|  | var completer = new Completer(); | 
|  | completer.complete('value'); | 
|  |  | 
|  | Expect.throws(() => completer.completeError('another value')); | 
|  | } |