Merge pull request #3 in G/truffle from ~MICHAEL.VAN.DE.VANTER_ORACLE.COM/truffle:fix-REPL-kill to master

Update the REPL debugger after change in handling of KillException.

* commit '34a435271d216211c708cf233a25df31abcf0565':
  REPL - tighten identification of KillException without dependency.
  REPL debugger:  fix handling of Kill reimplemented as subclass of ThreadDeath.

Author: mlvdv

truffle/com.oracle.truffle.tools.debug.shell/src/com/oracle/truffle/tools/debug/shell/client/REPLClientContext.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -98,9 +98,9 @@ interface REPLClientContext {
     void displayFailReply(String message);
 
     /**
-     * Send a message announcing current execution is being killed.
+     * notifies client that current execution has been killed.
      */
-    void displayKillMessage(String message);
+    void notifyKilled();
 
     /**
      * Recompute the client's command line prompt.

truffle/com.oracle.truffle.tools.debug.shell/src/com/oracle/truffle/tools/debug/shell/client/REPLRemoteCommand.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -567,14 +567,13 @@ public com.oracle.truffle.tools.debug.shell.REPLMessage createRequest(REPLClient
             }
             final com.oracle.truffle.tools.debug.shell.REPLMessage request = new com.oracle.truffle.tools.debug.shell.REPLMessage();
             request.put(com.oracle.truffle.tools.debug.shell.REPLMessage.OP, "kill");
-            context.displayKillMessage(null);
             return request;
         }
 
         @Override
         void processReply(REPLClientContext context, com.oracle.truffle.tools.debug.shell.REPLMessage[] replies) {
             if (replies[0].get(com.oracle.truffle.tools.debug.shell.REPLMessage.STATUS).equals(com.oracle.truffle.tools.debug.shell.REPLMessage.SUCCEEDED)) {
-                context.displayReply(replies[0].get(com.oracle.truffle.tools.debug.shell.REPLMessage.DISPLAY_MSG));
+                context.notifyKilled();
             } else {
                 context.displayFailReply(replies[0].get(com.oracle.truffle.tools.debug.shell.REPLMessage.DISPLAY_MSG));
             }

truffle/com.oracle.truffle.tools.debug.shell/src/com/oracle/truffle/tools/debug/shell/client/SimpleREPLClient.java

@@ -63,9 +63,6 @@
  * <p>
  * In order to get
  * <ol>
- * <li>A debugging session should start from this shell, but there is no machinery in place for
- * doing that; instead, an entry into the language implementation creates both the server and this
- * shell;</li>
  * <li>The current startup sequence is based on method calls, not messages;</li>
  * <li>Only a very few request types and keys are implemented, omitting for example request and
  * session ids;</li>
@@ -279,6 +276,10 @@ private class ClientContextImpl implements REPLClientContext {
 
         private String currentPrompt;
 
+        // A execution context stacked on top of this one was explicitly
+        // killed, and this context will receive the resulting exception.
+        private boolean killPending;
+
         /**
          * Create a new context on the occasion of an execution halting.
          */
@@ -519,7 +520,12 @@ public void displayFailReply(String message) {
             }
         }
 
-        public void displayKillMessage(String message) {
+        public void notifyKilled() {
+            // A kill will not be received until after
+            // This context is released, so the exception
+            // must be handles specially by the
+            // context that will catch it.
+            predecessor.killPending = true;
             writer.println(clientContext.currentPrompt + " killed");
         }
 
@@ -606,7 +612,16 @@ private void startContextSession() {
                     } else {
                         assert false; // Should not happen.
                     }
-
+                } catch (ThreadDeath ex) {
+                    if (ex.getClass() != ThreadDeath.class && killPending) {
+                        // If the previous context was killed by REPL command, then
+                        // assume this exception is the result and the REPL should
+                        // continue debugging in this context.
+                        killPending = false;
+                    } else {
+                        // A legitimate use of the exception
+                        throw ex;
+                    }
                 } catch (REPLContinueException ex) {
                     break;
                 } catch (IOException e) {