dart2js.

runtime/lib/isolate_patch.dart

 // Copyright (c) 2012, 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.
 
 patch class ReceivePort {
   /* patch */ factory ReceivePort() = _ReceivePortImpl;
 
   /* patch */ factory ReceivePort.fromRawReceivePort(RawReceivePort rawPort) =
       _ReceivePortImpl.fromRawReceivePort;
 }
@@ skipping 22 matching lines @@
   }
 
   SendPort get sendPort {
     return _rawPort.sendPort;
   }
 
   StreamSubscription listen(void onData(var message),
                             { Function onError,
                               void onDone(),
                               bool cancelOnError }) {
-    return _controller.stream.listen(onData);
+    return _controller.stream.listen(onData,
+                                     onError: onError,
+                                     onDone: onDone,
+                                     cancelOnError: cancelOnError);
   }
 
   close() {
     _rawPort.close();
     _controller.close();
   }
 
   final RawReceivePort _rawPort;
   StreamController _controller;
 }
@@ skipping 148 matching lines @@
       // TODO(floitsch): we want errors to go into the returned future.
       rethrow;
     };
     return completer.future;
   }
 
   /* patch */ static Future<Isolate> spawnUri(
       Uri uri, List<String> args, var message) {
     Completer completer = new Completer<Isolate>.sync();
     try {
+      if (args is List<String>) {
+        for (int i = 0; i < args.length; i++) {
+          if (args[i] is! String) {
+            throw new ArgumentError("Args must be a list of Strings $args");
+          }
+        }
+      } else if (args != null) {
+        throw new ArgumentError("Args must be a list of Strings $args");

[Lasse Reichstein Nielsen, 2013/10/25 14:28:24]

If we allow null, will it be null at the other end too, or an empty list?

[floitsch, 2013/10/25 14:33:14]

I would say `null`.

+      }
       // The VM will invoke [_startIsolate] and not `main`.
       SendPort controlPort = _spawnUri(uri.path);
       RawReceivePort readyPort = new RawReceivePort();
       controlPort.send([readyPort.sendPort, args, message]);
       readyPort.handler = (readyMessage) {
         assert(readyMessage == 'started');
         readyPort.close();
         completer.complete(new Isolate._fromControlPort(controlPort));
       };
     } catch(e, st) {
       // TODO(floitsch): we want errors to go into the returned future.
       rethrow;
     };
     return completer.future;
   }
 
   static final ReceivePort _port =
       new ReceivePort.fromRawReceivePort(_getPortInternal());
 
   static SendPort _spawnFunction(Function topLevelFunction)
       native "isolate_spawnFunction";
 
   static SendPort _spawnUri(String uri) native "isolate_spawnUri";
 }