LibTest/async/StreamController/StreamController.broadcast_Stream_all_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.

/**
 * @assertion StreamController.broadcast({void onListen(), void onCancel(),
 *                                       bool sync: false})
 * A controller where stream can be listened to more than once.
 *
 * The Stream returned by stream is a broadcast stream. It can be listened to
 * more than once.
 *
 * The controller distributes any events to all currently subscribed listeners
 * at the time when add, addError or close is called.
 *
 * @description Checks that property stream implements Stream interface
 * @author a.semenov@unipro.ru
 */
import "dart:async";
import "../Stream/allTests_A01.lib.dart";

Stream<T> create<T>(Iterable<T> data, {bool isError(T element)?}) {
  StreamController<T>? sc;
  sc = new StreamController<T>.broadcast(
    sync: true,
    onListen: () {
      new Future(() {
        for (T e in data) {
          if (sc!.isClosed){
            break;
          }
          if (isError != null && isError(e)) {
            sc.addError(e as Object);
          } else {
            sc.add(e);
          }
        }
      }).then((_) => sc?.close());
    },
    onCancel: () {
      sc?.close();
    }
  );
  return sc.stream;
}

main() {
  test(create);
}