Adapt streams for additional stackTrace argument.

pkg/barback/lib/src/utils.dart

 // Copyright (c) 2013, 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.
 
 library barback.utils;
 
 import 'dart:async';
 
 /// A pair of values.
 class Pair<E, F> {
@@ skipping 119 matching lines @@
   streams = streams.toList();
   var doneCount = 0;
   // Use a sync stream to preserve the synchrony behavior of the input streams.
   // If the inputs are sync, then this will be sync as well; if the inputs are
   // async, then the events we receive will also be async, and forwarding them
   // sync won't change that.
   var controller = broadcast ? new StreamController.broadcast(sync: true)
       : new StreamController(sync: true);
 
   for (var stream in streams) {
-    stream.listen((value) {
-      controller.add(value);
-    }, onError: (error) {
-      controller.addError(error);
-    }, onDone: () {
-      doneCount++;
-      if (doneCount == streams.length) controller.close();
-    });
+    stream.listen(
+      controller.add,
+      onError: controller.addError,
+      onDone: () {
+        doneCount++;
+        if (doneCount == streams.length) controller.close();
+      });

[nweiz, 2013/10/07 18:49:51]

The indentation here is wrong. It should be:

stream.listen(
    controller.add,
    onError: controller.addError,
    onDone: () {
  doneCount++;
  if (odneCount == streams.length) controller.close();
});

[floitsch, 2013/10/10 14:22:52]

Done.

   }
 
   return controller.stream;
 }
 
 /// Prepends each line in [text] with [prefix]. If [firstPrefix] is passed, the
 /// first line is prefixed with that instead.
 String prefixLines(String text, {String prefix: '| ', String firstPrefix}) {
   var lines = text.split('\n');
   if (firstPrefix == null) {
@@ skipping 23 matching lines @@
 Future newFuture(callback()) => new Future.value().then((_) => callback());
 
 /// Returns a buffered stream that will emit the same values as the stream
 /// returned by [future] once [future] completes. If [future] completes to an
 /// error, the return value will emit that error and then close.
 Stream futureStream(Future<Stream> future) {
   var controller = new StreamController(sync: true);
   future.then((stream) {
     stream.listen(
         controller.add,
-        onError: (error) => controller.addError(error),
+        onError: controller.addError,
         onDone: controller.close);
-  }).catchError((e) {
-    controller.addError(e);
+  }).catchError((e, StackTrace stackTrace) {

[nweiz, 2013/10/07 18:49:51]

Should this stackTrace parameter be optional? It's optional for [stream.listen].

[floitsch, 2013/10/10 14:22:52]

We know where the catchError comes from. (It's from one of our Controllers).
Therefore we know it knows how to deal with 2 arg functions.
We use the optional 2nd argument when the receive might be a user-supplied
Future/Stream that doesn't know anything about 2-arg handlers yet. (To minimize
breakage).

+    controller.addError(e, stackTrace);
     controller.close();
   });
   return controller.stream;
 }