| // Copyright (c) 2018, 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 Future<RawSocketEvent> elementAt(int index) |
| /// Returns the value of the indexth data event of this stream. |
| /// |
| /// Stops listening to the stream after the indexth data event has been received. |
| /// |
| /// Internally the method cancels its subscription after these elements. This |
| /// means that single-subscription (non-broadcast) streams are closed and cannot |
| /// be reused after a call to this method. |
| /// |
| /// If an error event occurs before the value is found, the future completes with |
| /// this error. |
| /// |
| /// @description Checks that if receiver RawDatagramSocket is closed before |
| /// method 'elementAt' calling, this stream contains only one element |
| /// RawSocketEvent.closed. |
| /// @author ngl@unipro.ru |
| |
| import "dart:async"; |
| import "dart:io"; |
| import "../http_utils.dart"; |
| import "../../../Utils/expect.dart"; |
| |
| var localhost = InternetAddress.loopbackIPv4; |
| |
| Future<RawSocketEvent> checkElementAt(int index) async { |
| RawDatagramSocket producer = await RawDatagramSocket.bind(localhost, 0); |
| RawDatagramSocket receiver = await RawDatagramSocket.bind(localhost, 0); |
| List<List<int>> toSend = [[0, 1, 2, 3], [1, 2, 3]]; |
| Completer<RawSocketEvent> completer = new Completer<RawSocketEvent>(); |
| Future<RawSocketEvent> f = completer.future; |
| |
| bool wasSent = await sendDatagram(producer, toSend, localhost, receiver.port); |
| Expect.isTrue(wasSent, "No datagram was sent"); |
| receiver.close(); |
| |
| Future fValue = receiver.elementAt(index); |
| fValue.then((value) { |
| if (!completer.isCompleted) { |
| completer.complete(value); |
| } |
| return f; |
| }); |
| |
| return f; |
| } |
| |
| main() async { |
| int attempts = 5; |
| |
| for (int i = 0; i < attempts; i++) { |
| RawSocketEvent value = await checkElementAt(0); |
| if (value == RawSocketEvent.closed) { |
| break; |
| } |
| |
| if (i == attempts - 1) { |
| print('$value element not found. Look like test failed.'); |
| } |
| } |
| } |