- Implement Isolate.ping.

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.
 
 import "dart:collection" show HashMap;
 
 patch class ReceivePort {
   /* patch */ factory ReceivePort() = _ReceivePortImpl;
 
   /* patch */ factory ReceivePort.fromRawReceivePort(RawReceivePort rawPort) =
@@ skipping 304 matching lines @@
       return new Future<Isolate>.error(e, st);
     };
     return completer.future;
   }
 
   // TODO(iposva): Cleanup to have only one definition.
   // These values need to be kept in sync with the class IsolateMessageHandler
   // in vm/isolate.cc.
   static const _PAUSE = 1;
   static const _RESUME = 2;
+  static const _PING = 3;
+
 
   static SendPort _spawnFunction(SendPort readyPort, Function topLevelFunction,
                                  var message)
       native "Isolate_spawnFunction";
 
   static SendPort _spawnUri(SendPort readyPort, String uri,
                             List<String> args, var message,
                             String packageRoot)
       native "Isolate_spawnUri";
 
@@ skipping 27 matching lines @@
 
   /* patch */ void setErrorsFatal(bool errorsAreFatal) {
     throw new UnsupportedError("setErrorsFatal");
   }
 
   /* patch */ void kill([int priority = BEFORE_NEXT_EVENT]) {
     throw new UnsupportedError("kill");
   }
 
   /* patch */ void ping(SendPort responsePort, [int pingType = IMMEDIATE]) {
-    throw new UnsupportedError("ping");
+    var msg = new List(4)
+        ..[0] = 0  // Make room for OOM message type.
+        ..[1] = _PING
+        ..[2] = responsePort
+        ..[3] = pingType;
+    _sendOOB(controlPort, msg);
   }
 
   /* patch */ void addErrorListener(SendPort port) {
     throw new UnsupportedError("addErrorListener");
   }
 
   /* patch */ void removeErrorListener(SendPort port) {
     throw new UnsupportedError("removeErrorListener");
   }
 }