LibTest/async/StreamIterator/current_A01_t03.dart

// Copyright (c) 2016, 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 T current
/// The current value of the stream.
///
/// Is null before the first call to moveNext and after a call to moveNext
/// completes with a false result or an error.
///
/// When a moveNext call completes with true, the current field holds the most
/// recent event of the stream, and it stays like that until the next call to
/// moveNext. Between a call to moveNext and when its returned future completes,
/// the value is unspecified.
///
/// @description Checks that the property current returns null after a call to
/// moveNext completes with an error.
/// @author ngl@unipro.ru

import "dart:async";
import "../../../Utils/expect.dart";

main() {
  StreamController c = new StreamController();
  StreamIterator si = new StreamIterator(c.stream);
  asyncStart();
  c.addError(1);

  si.moveNext().catchError((value) {
    Expect.equals(1, value);
    Expect.isNull(si.current);
    asyncEnd();
    return new Future.value(false);
  });
}