Don't consider controller.addError to be a zone-crossing.

tests/lib/async/stream_zones_test.dart

+// Copyright (c) 2014, 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 'package:async_helper/async_helper.dart';
+import "package:expect/expect.dart";
+import 'dart:async';
+
+/// StreamController in nested runZoned. Trivial.
+test1() {
+  var events = [];
+  var done = new Completer();
+  runZoned(() {
+    runZoned(() {
+      var c = new StreamController();
+      c.stream.listen(
+          (x) => events.add("stream: $x"),
+           onError: (x) => events.add("stream: error $x"),
+           onDone: done.complete);
+      c.add(1);
+      c.addError(2);
+      c.close();
+    }, onError: (x) => events.add("rza: error $x"));
+  }, onError: (x) => events.add("rzb: error $x"));
+  return [done.future, () {
+    Expect.listEquals(["stream: 1", "stream: error 2"], events);
+  }];
+}
+
+/// Adding errors to the stream controller from an outside zone.
+test2() {
+  var events = [];
+  var done = new Completer();
+  runZoned(() {
+    var c;
+    runZoned(() {
+      c = new StreamController();
+      c.stream.listen(
+          (x) => events.add("stream: $x"),
+           onError: (x) => events.add("stream: error $x"),
+           onDone: done.complete);
+    }, onError: (x) => events.add("rza: error $x"));
+    c.add(1);
+    c.addError(2);
+    c.close();
+  }, onError: (x) => events.add("rzb: error $x"));
+  return [done.future, () {
+    Expect.listEquals(["stream: 1", "stream: error 2"], events);
+  }];
+}
+
+/// Adding errors to the stream controller from a more nested zone.
+test3() {
+  var events = [];
+  var done = new Completer();
+  runZoned(() {
+    var c = new StreamController();
+    c.stream.listen(
+        (x) => events.add("stream: $x"),
+          onError: (x) => events.add("stream: error $x"),
+          onDone: done.complete);
+    runZoned(() {
+      c.add(1);
+      c.addError(2);
+      c.close();
+    }, onError: (x) => events.add("rza: error $x"));
+  }, onError: (x) => events.add("rzb: error $x"));
+  return [done.future, () {
+    Expect.listEquals(["stream: 1", "stream: error 2"], events);
+  }];
+}
+
+/// Feeding a stream from a different zone into another controller.
+test4() {
+  var events = [];
+  var done = new Completer();
+  runZoned(() {
+    var c = new StreamController();
+    c.stream.listen(
+        (x) => events.add("stream: $x"),
+          onError: (x) => events.add("stream: error $x"),
+          onDone: done.complete);
+    runZoned(() {
+      var c2 = new StreamController();
+      c.addStream(c2.stream).whenComplete(c.close);
+      c2.add(1);
+      c2.addError(2);
+      c2.close();
+    }, onError: (x) => events.add("rza: error $x"));
+  }, onError: (x) => events.add("rzb: error $x"));
+  return [done.future, () {
+    Expect.listEquals(["stream: 1", "stream: error 2"], events);
+  }];
+}
+
+/// Feeding a stream from a different zone into another controller.
+/// This time nesting is reversed wrt test4.
+test5() {
+  var events = [];
+  var done = new Completer();
+  runZoned(() {
+    var c;
+    runZoned(() {
+      c = new StreamController();
+      c.stream.listen(
+          (x) => events.add("stream: $x"),
+            onError: (x) => events.add("stream: error $x"),
+            onDone: done.complete);
+    }, onError: (x) => events.add("rza: error $x"));
+    var c2 = new StreamController();
+    c.addStream(c2.stream).whenComplete(c.close);
+    c2.add(1);
+    c2.addError(2);
+    c2.close();
+  }, onError: (x) => events.add("rzb: error $x"));
+  return [done.future, () {
+    Expect.listEquals(["stream: 1", "stream: error 2"], events);
+  }];
+}
+

[Lasse Reichstein Nielsen, 2014/07/10 09:45:17]

All the tests have nested zones. How about independent zones:

  var c;
  runZoned(() { c = new StreamController(); ... });
  runZoned(() { c.add(...)...});

?

[floitsch, 2014/07/10 13:50:42]

Done.

+main() {
+  asyncStart();
+
+  var tests = [
+    test1(),
+    test2(),
+    test3(),
+    test4(),
+    test5(),
+  ];
+
+  Future.wait(tests.map((l) => l.first)).then((_) {
+    // Give time to complete all pending actions.
+    Timer.run(() {
+      tests.forEach((l) => (l.last)());
+      asyncEnd();
+    });
+  });
+}