LibTest/async/Completer/complete_A02_t01.dart

// 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.

// @dart = 2.9

/// @assertion void complete([T value])
/// 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();
  var future = completer.future;
  completer.complete('value');

  Expect.throws(() => completer.complete('another value'));
}