Support for lists in debugger wire protocol

tools/ddbg.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.
 
 // Simple interactive debugger shell that connects to the Dart VM's debugger
 // connection port.
 
 #import("dart:io");
 #import("dart:json");
 
@@ skipping 18 matching lines @@
   print("""
   q   Quit debugger shell
   bt  Show backtrace
   r   Resume execution
   s   Single step
   so  Step over
   si  Step into
   sbp [<file>] <line> Set breakpoint
   rbp <id> Remove breakpoint with given id
   po <id> Print object info for given id
+  pl <id> <idx> [<len>] Print list element/slice
   pc <id> Print class info for given id
   ll  List loaded libraries
-  pl <id> Print library info for given library id
+  plib <id> Print library info for given library id
   pg <id> Print all global variables visible within given library id
   ls <libname> List loaded scripts in library
   gs <lib_id> <script_url> Get source text of script in library
   epi <none|all|unhandled>  Set exception pause info
   h   Print help
 """);
 }
 
 
 void quitShell() {
@@ skipping 54 matching lines @@
     sendCmd(cmd).then((result) => handleGenericResponse(result));
   } else if (command == "ls" && args.length == 2) {
     var cmd = { "id": seqNum,
                 "command": "getScriptURLs",
                 "params": { "libraryId": Math.parseInt(args[1]) }};
     sendCmd(cmd).then((result) => handleGetScriptsResponse(result));
   } else if (command == "po" && args.length == 2) {
     var cmd = { "id": seqNum, "command": "getObjectProperties",
                 "params": {"objectId": Math.parseInt(args[1]) }};
     sendCmd(cmd).then((result) => handleGetObjPropsResponse(result));
+  } else if (command == "pl" && args.length >= 3) {
+     var cmd;
+     if (args.length == 3) {
+       cmd = { "id": seqNum, "command": "getListElements",
+                "params": {"objectId": Math.parseInt(args[1]),
+                            "index": Math.parseInt(args[2]) }};
+    } else {
+       cmd = { "id": seqNum, "command": "getListElements",
+                "params": {"objectId": Math.parseInt(args[1]),
+                            "index": Math.parseInt(args[2]),
+                            "length": Math.parseInt(args[3]) }};
+    }
+    sendCmd(cmd).then((result) => handleGetListResponse(result));
   } else if (command == "pc" && args.length == 2) {
     var cmd = { "id": seqNum, "command": "getClassProperties",
                 "params": {"classId": Math.parseInt(args[1]) }};
     sendCmd(cmd).then((result) => handleGetClassPropsResponse(result));
-  } else if (command == "pl" && args.length == 2) {
+  } else if (command == "plib" && args.length == 2) {
     var cmd = { "id": seqNum, "command": "getLibraryProperties",
                 "params": {"libraryId": Math.parseInt(args[1]) }};
     sendCmd(cmd).then((result) => handleGetLibraryPropsResponse(result));
   } else if (command == "pg" && args.length == 2) {
     var cmd = { "id": seqNum, "command": "getGlobalVariables",
                 "params": {"libraryId": Math.parseInt(args[1]) }};
     sendCmd(cmd).then((result) => handleGetGlobalVarsResponse(result));
   } else if (command == "gs" && args.length == 3) {
     var cmd = { "id": seqNum, "command":  "getScriptSource",
                 "params": { "libraryId": Math.parseInt(args[1]),
                             "url": args[2] }};
     sendCmd(cmd).then((result) => handleGetSourceResponse(result));
   } else if (command == "epi" && args.length == 2) {
     var cmd = { "id": seqNum, "command":  "setPauseOnException",
                 "params": { "exceptions": args[1] }};
     sendCmd(cmd).then((result) => handleGenericResponse(result));
   } else if (command == "q") {
     quitShell();
   } else if (command == "h") {
     printHelp();
   } else {
     print("command '$command' not understood, try h for help");
   }
 }
 
 
-String remoteValue(value) {
+String remoteObject(value) {
   var kind = value["kind"];
   var text = value["text"];
   var id = value["objectId"];
   if (kind == "string") {
-    return "'$text'";
+    return "(string, id $id) '$text'";
+  } else if (kind == "list") {
+    var len = value["length"];
+    return "(list, id $id, len $len) $text";
   } else if (kind == "object") {
-    return "(obj id: $id) = $text";
+    return "(obj, id $id) $text";
   } else {
     return "$text";
   }
 }
 
 
 printNamedObject(obj) {
   var name = obj["name"];
   var value = obj["value"];
-  print("  $name = ${remoteValue(value)}");
+  print("  $name = ${remoteObject(value)}");
 }
 
 
 handleGetObjPropsResponse(response) {
   Map props = response["result"];
   int class_id = props["classId"];
   if (class_id == -1) {
     print("  null");
     return;
   }
   List fields = props["fields"];
   print("  class id: $class_id");
   for (int i = 0; i < fields.length; i++) {
     printNamedObject(fields[i]);
   }
 }
 
+handleGetListResponse(response) {
+  Map result = response["result"];
+  if (result["elements"] != null) {
+    // List slice.
+    var index = result["index"];
+    var length = result["length"];
+    List elements = result["elements"];
+    assert(length == elements.length);
+    for (int i = 0; i < length; i++) {
+      var kind = elements[i]["kind"];
+      var text = elements[i]["text"];
+      print("  ${index + i}: ($kind) $text");
+    }
+  } else {
+    // One element, a remote object.
+    print(result);
+    print("  ${remoteObject(result)}");
+  }
+}
+
 
 handleGetClassPropsResponse(response) {
   Map props = response["result"];
   assert(props["name"] != null);
   int libId = props["libraryId"];
   assert(libId != null);
   print("  class ${props["name"]} (library id: $libId)");
   List fields = props["fields"];
   if (fields.length > 0) {
     print("  static fields:");
@@ skipping 112 matching lines @@
   stackTrace = msg["params"]["callFrames"];
   assert(stackTrace != null);
   assert(stackTrace.length >= 1);
   curFrame = stackTrace[0];
   if (reason == "breakpoint") {
     print("VM paused on breakpoint");
   } else {
     assert(reason == "exception");
     var excObj = msg["params"]["exception"];
     print("VM paused on exception");
-    print(remoteValue(excObj));
+    print(remoteObject(excObj));
   }
   print("Stack trace:");
   printStackTrace(stackTrace);
 }
 
 
 void processVmMessage(String json) {
   var msg = JSON.parse(json);
   if (msg == null) {
     return;
@@ skipping 71 matching lines @@
   };
   vmInStream.onError = (err) {
     print("Error in debug connection: $err");
     quitShell();
   };
   vmInStream.onClosed = () {
     print("VM debugger connection closed");
     quitShell();
   };
 }