LibTest/io/IOSink/flush_A02_t01.dart

// Copyright (c) 2017, 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 Future flush()
/// This method must not be called while an [addStream] is incomplete.
/// @description Checks that [flush] causes error if [addStream] is currently
/// incomplete.
/// @author iarkh@unipro.ru

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

class MyStreamConsumer extends StreamConsumer<List<int>> {
  MyStreamConsumer() {}
  Future addStream(Stream<List> stream) { return new Future(() {}); }
  Future close() { return new Future(() => {}); }
}

main() {
  Stream<List<int>> stream = new Stream<List<int>>.fromIterable([[1, 2]]);
  StreamConsumer consumer = new MyStreamConsumer();
  IOSink sink = new IOSink(consumer);
  sink.addStream(stream).then((x) {
    new Future.delayed(new Duration(seconds: 3)).then((_) { sink.close(); });
  });
  Expect.throws(() { sink.flush(); }, (e) => e is StateError);
}