Provide more error-handling customization.

lib/stream_channel.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.
 
 import 'dart:async';
 
 import 'package:async/async.dart';
 
 import 'src/guarantee_channel.dart';
 import 'src/stream_channel_transformer.dart';
@@ skipping 60 matching lines @@
   /// StreamChannel.withGuarantees] should be used instead.
   factory StreamChannel(Stream<T> stream, StreamSink<T> sink) =>
       new _StreamChannel<T>(stream, sink);
 
   /// Creates a new [StreamChannel] that communicates over [stream] and [sink].
   ///
   /// Unlike [new StreamChannel], this enforces the guarantees listed in the
   /// [StreamChannel] documentation. This makes it somewhat less efficient than
   /// just wrapping a stream and a sink directly, so [new StreamChannel] should
   /// be used when the guarantees are provided natively.
-  factory StreamChannel.withGuarantees(Stream<T> stream, StreamSink<T> sink) =>
-      new GuaranteeChannel(stream, sink);
+  ///
+  /// If [allowSinkErrors] is `false`, errors are not allowed to be passed to
+  /// [sink]. If any are, the connection will close and the error will be
+  /// forwarded to [Sink.done].
+  factory StreamChannel.withGuarantees(Stream<T> stream, StreamSink<T> sink,
+          {bool allowSinkErrors: true}) =>
+      new GuaranteeChannel(stream, sink, allowSinkErrors: allowSinkErrors);
 
   /// Connects [this] to [other], so that any values emitted by either are sent
   /// directly to the other.
   void pipe(StreamChannel<T> other);
 
   /// Transforms [this] using [transformer].
   ///
   /// This is identical to calling `transformer.bind(channel)`.
   StreamChannel transform(StreamChannelTransformer<T, dynamic> transformer);
 
@@ skipping 40 matching lines @@
 
   StreamChannel<T> transformSink(StreamSinkTransformer<T, T> transformer) =>
       changeSink(transformer.bind);
 
   StreamChannel<T> changeStream(Stream<T> change(Stream<T> stream)) =>
       new StreamChannel(change(stream), sink);
 
   StreamChannel<T> changeSink(StreamSink<T> change(StreamSink<T> sink)) =>
       new StreamChannel(stream, change(sink));
 }