Add type checks to directory listing.

runtime/bin/directory_impl.dart

Index: runtime/bin/directory_impl.dart
diff --git a/runtime/bin/directory_impl.dart b/runtime/bin/directory_impl.dart
index 127d68b475f7b67bb9e25a09ead14e6ef74bfbf7..f4f062c0e39e64aee347b6b42dff698d19b1ed0e 100644
--- a/runtime/bin/directory_impl.dart
+++ b/runtime/bin/directory_impl.dart
@@ -3,30 +3,23 @@
 // BSD-style license that can be found in the LICENSE file.
 
 
-class DirectoryException {
-  String toString() { return "DirectoryException: $message"; }
-  const DirectoryException(String this.message);
-  final String message;
-}
-
-
 class _DirectoryListingIsolate extends Isolate {
 
   _DirectoryListingIsolate() : super.heavy();
 
   void main() {
     port.receive((message, replyTo) {
-       _list(message['dir'],
-             message['recursive'],
-             message['dirPort'],
-             message['filePort'],
-             message['donePort'],
-             message['errorPort']);
-       replyTo.send(true);
+      bool started = _list(message['dir'],
+                           message['recursive'],
+                           message['dirPort'],
+                           message['filePort'],
+                           message['donePort'],
+                           message['errorPort']);
+      replyTo.send(started);
     });
   }
 
-  void _list(String dir,
+  bool _list(String dir,
              bool recursive,
              SendPort dirPort,
              SendPort filePort,
@@ -91,14 +84,14 @@ class _Directory implements Directory {
         listingParameters['filePort'] = filePort.toSendPort();
       }
       if (_doneHandler !== null) {
-        donePort = new ReceivePort();
+        donePort = new ReceivePort.singleShot();
         donePort.receive((bool completed, ignored) {
           _doneHandler(completed);
         });
         listingParameters['donePort'] = donePort.toSendPort();
       }
       if (_errorHandler !== null) {
-        errorPort = new ReceivePort();
+        errorPort = new ReceivePort.singleShot();
         errorPort.receive((String error, ignored) {
           _errorHandler(error);
         });
@@ -108,10 +101,16 @@ class _Directory implements Directory {
       // Close ports when listing is done.
       ReceivePort closePortsPort = new ReceivePort();
       closePortsPort.receive((message, replyTo) {
+        if (!message) {
+          errorPort.toSendPort().send(
+              "Failed to list directory: $_path recursive: $recursive");
+          donePort.toSendPort().send(false);
+        } else {
+          _closePort(errorPort);
+          _closePort(donePort);
+        }
         _closePort(dirPort);
         _closePort(filePort);

[Søren Gjesse, 2011/10/28 13:05:55]

Shouldn't the error port be closed if everything ends normally?

[Mads Ager (google), 2011/10/28 15:58:16]

It is on line 109. If listing does not start the single shot error and done
ports are signaled which will close them. Otherwise they will be closed
explicitly in the else branch.

-        _closePort(donePort);
-        _closePort(errorPort);
         _closePort(closePortsPort);
       });