Inspect local variables and fields from service protocol.

pkg/dartino_compiler/lib/src/debug_service_protocol.dart

Index: pkg/dartino_compiler/lib/src/debug_service_protocol.dart
diff --git a/pkg/dartino_compiler/lib/src/debug_service_protocol.dart b/pkg/dartino_compiler/lib/src/debug_service_protocol.dart
index c21df67cc9e8f4c913bc81f548c29eddb31339ba..bfa498172781df2dbbabd51e20f7375744072290 100644
--- a/pkg/dartino_compiler/lib/src/debug_service_protocol.dart
+++ b/pkg/dartino_compiler/lib/src/debug_service_protocol.dart
@@ -6,7 +6,6 @@
 /// Processes are mapped to isolates.
 // TODO(sigurdm): Handle processes better.
 // TODO(sigurdm): Find a way to represent fibers.
-// TODO(sigurdm): Represent remote values.
 // TODO(sigurdm): Use https://pub.dartlang.org/packages/json_rpc_2 for serving.
 
 import "dart:async" show Future;
@@ -20,7 +19,15 @@ import 'hub/session_manager.dart' show SessionState;
 import 'guess_configuration.dart' show dartinoVersion;
 
 import '../debug_state.dart'
-    show BackTrace, BackTraceFrame, Breakpoint, RemoteObject;
+    show
+        BackTrace,
+        BackTraceFrame,
+        Breakpoint,
+        RemoteArray,
+        RemoteErrorObject,
+        RemoteInstance,
+        RemoteObject,
+        RemoteValue;
 
 import '../vm_context.dart' show DartinoVmContext, DebugListener;
 
@@ -31,10 +38,20 @@ import 'debug_info.dart' show DebugInfo, ScopeInfo, SourceLocation;
 
 import 'dartino_compiler_implementation.dart'
     show DartinoCompilerImplementation;
-
-import 'codegen_visitor.dart' show LocalValue;
+import 'element_utils.dart';
 
 import '../program_info.dart' show Configuration;
+import '../vm_commands.dart'
+    show
+        Array,
+        Boolean,
+        ClassValue,
+        DartValue,
+        Double,
+        Instance,
+        Integer,
+        NullValue,
+        StringValue;
 
 import 'package:collection/collection.dart' show binarySearch;
 
@@ -44,8 +61,10 @@ import 'package:compiler/src/io/source_file.dart' show SourceFile;
 import 'package:compiler/src/elements/visitor.dart' show BaseElementVisitor;
 import 'package:compiler/src/elements/elements.dart'
     show
+        ClassElement,
         CompilationUnitElement,
         Element,
+        FieldElement,
         FunctionElement,
         LibraryElement,
         MemberElement,
@@ -53,43 +72,6 @@ import 'package:compiler/src/elements/elements.dart'
 
 const bool logging = const bool.fromEnvironment("dartino-log-debug-server");
 
-//TODO(danrubel): Verify const map values
-const Map<String, dynamic> dartCoreLibRefDesc = const <String, dynamic>{
-  "type": "@Library",
-  "id": "libraries/dart:core",
-  "fixedId": true,
-  "name": "dart:core",
-  "uri": "dart:core",
-};
-
-//TODO(danrubel): Verify correct id
-const String nullId = "objects/Null";
-
-//TODO(danrubel): Verify const map values
-const Map<String, dynamic> nullClassRefDesc = const <String, dynamic>{
-  "type": "@Class",
-  "id": "classes/NullClass",
-  "name": "NullClass",
-};
-
-//TODO(danrubel): Verify const map values
-const Map<String, dynamic> nullRefDesc = const <String, dynamic>{
-  "type": "@Null",
-  "id": nullId,
-  "kind": "Null",
-  "class": nullClassRefDesc,
-  "valueAsString": "null",
-};
-
-//TODO(danrubel): Verify const map values
-const Map<String, dynamic> nullDesc = const <String, dynamic>{
-  "type": "Null",
-  "id": nullId,
-  "kind": "Null",
-  "class": nullClassRefDesc,
-  "valueAsString": "null",
-};
-
 class DebugServer {
   Future<int> serveSingleShot(SessionState state,
       {int port: 0, Uri snapshotLocation}) async {
@@ -145,16 +127,20 @@ class DebugConnection implements DebugListener {
   Map<String, CompilationUnitElement> scripts =
       new Map<String, CompilationUnitElement>();
 
-  Map frameDesc(BackTraceFrame frame, int index) {
+  Future<Map> frameDesc(BackTraceFrame frame, int index) async {
     List<Map> vars = new List<Map>();
     for (ScopeInfo current = frame.scopeInfo();
         current != ScopeInfo.sentinel;
         current = current.previous) {
+      RemoteValue remoteValue =
+          await vmContext.processLocal(index, current.local.slot);
       vars.add({
         "type": "BoundVariable",
         "name": current.name,
-        "value": valueDesc(current.lookup(current.name))
+        "value": instanceRef(
+            remoteValue.value, "objects/$index.${current.local.slot}"),
       });
+      print("Adding ${vars.last}");

[Søren Gjesse, 2016/06/15 11:26:18]

Debug print.

[sigurdm, 2016/06/17 07:29:32]

Done.

     }
     return {
       "type": "Frame",
@@ -338,10 +324,136 @@ class DebugConnection implements DebugListener {
     };
   }
 
-  Map valueDesc(LocalValue lookup) {
-    //TODO(danrubel): Translate local value into description?
-    // Need to return an @InstanceRef or Sentinel
-    return nullRefDesc;
+  Map classRef(ClassElement classElement) {
+    if (classElement == null) {
+      return {"type": "@Class", "id": "unknown", "name": "unknown class"};
+    }
+    String symbolicName =
+        "${classElement.library.canonicalUri}.${classElement.name}";
+    return {
+      "type": "@Class",
+      "id": "classes/$symbolicName",
+      "name": "${classElement.name}",
+    };
+  }
+
+  Map instanceRef(DartValue value, String id) {
+    int classId;
+    Element classElement;
+    String stringValue;
+    String kind;
+    int length;
+    String name;
+    if (value is Instance) {
+      kind = "PlainInstance";
+      classId = value.classId;
+    } else if (value is Integer) {
+      kind = "Int";
+      classElement = vmContext.compiler.compiler.backend.intImplementation;
+      stringValue = "${value.value}";
+    } else if (value is StringValue) {
+      kind = "String";
+      classElement = vmContext.compiler.compiler.backend.stringImplementation;
+      stringValue = value.value;
+    } else if (value is Boolean) {
+      kind = "Bool";
+      classElement = vmContext.compiler.compiler.backend.boolImplementation;
+      stringValue = "${value.value}";
+    } else if (value is Double) {
+      kind = "Double";
+      classElement = vmContext.compiler.compiler.backend.doubleImplementation;
+      stringValue = "${value.value}";
+    } else if (value is ClassValue) {
+      kind = "Type";
+      Element element =
+          vmContext.dartinoSystem.classesById[value.classId].element;
+      classElement = vmContext.compiler.compiler.backend.typeImplementation;
+      name = "${element}";
+    } else if (value is NullValue) {
+      kind = "Null";
+      classElement = vmContext.compiler.compiler.backend.nullImplementation;
+      stringValue = "null";
+    } else if (value is Array) {
+      kind = "List";
+      classElement = vmContext.compiler.compiler.backend.listImplementation;
+      length = value.length;
+    } else {
+      throw "Unexpected remote value $value";
+    }
+    print("classId $classId element $classElement");

[Søren Gjesse, 2016/06/15 11:26:18]

Debug print.

[sigurdm, 2016/06/17 07:29:32]

Done.

+    Map classReference = classRef(
+        classElement ?? vmContext.dartinoSystem.classesById[classId]?.element);
+    Map result = {
+      "type": "@Instance",
+      "id": id,
+      "kind": kind,
+      "class": classReference,
+    };
+    if (stringValue != null) {
+      result["valueAsString"] = stringValue;
+    }
+    if (length != null) {
+      result["length"] = length;
+    }
+    if (name != null) {
+      result["name"] = name;
+    }
+    return result;
+  }
+
+  Map instanceDesc(RemoteObject remoteObject, String id) {
+    // TODO(sigurdm): Allow inspecting any frame.
+    assert(remoteObject is! RemoteErrorObject);
+    if (remoteObject is RemoteInstance) {
+      int classId = remoteObject.instance.classId;
+      Element classElement =
+          vmContext.dartinoSystem.classesById[classId].element;
+      List<FieldElement> fieldElements = computeFields(classElement);
+      assert(fieldElements.length == remoteObject.fields.length);
+      List fields = new List();
+      for (int i = 0; i < fieldElements.length; i++) {
+        FieldElement fieldElement = fieldElements[i];
+        fields.add({
+          "type": "BoundField",
+          "decl": {
+            "type": "@Field",
+            "name": fieldElement.name,
+            "owner": classRef(fieldElement.contextClass),
+            "declaredType": null, // TODO(sigurdm): fill this in.
+            "const": fieldElement.isConst,
+            "final": fieldElement.isFinal,
+            "static": fieldElement.isStatic,
+          },
+          "value": instanceRef(remoteObject.fields[i], "$id.$i"),
+        });
+      }
+      return <String, dynamic>{
+        "type": "Instance",
+        "id": id,
+        "kind": "PlainInstance",
+        "class": classRef(classElement),
+        "fields": fields,
+      };
+    } else if (remoteObject is RemoteArray) {

[Søren Gjesse, 2016/06/15 11:26:18]

Probably want to have a TODO on handling large arrays, so that only part of the
elements are transferred initially, and then can be fetched on demand.

Does the protocol support the concept of partial arrays?

[sigurdm, 2016/06/17 07:29:32]

Added TODO.
It does - I don't know the details of how it works though.

+      List elements = new List();
+      for (int i = 0; i < remoteObject.array.length; i++) {
+        elements.add(instanceRef(remoteObject.values[i], "$id.$i"));
+      }
+      return <String, dynamic>{
+        "type": "Instance",
+        "id": id,
+        "kind": "List",
+        "class":
+            classRef(vmContext.compiler.compiler.backend.listImplementation),
+        "elements": elements,
+      };
+    } else if (remoteObject is RemoteValue) {
+      Map instance = instanceRef(remoteObject.value, id);
+      instance["type"] = "Instance";
+      return instance;
+    } else {
+      throw "Unexpected remote object kind";
+    }
   }
 
   initialize(DartinoCompilerImplementation compiler) {
@@ -504,13 +616,15 @@ class DebugConnection implements DebugListener {
                   int.parse(id.substring(slashIndex + 1))]));
               break;
             case "objects":
-              if (id == nullId) {
-                sendResult(nullDesc);
-              } else {
-                //TODO(danrubel): Need to return an Instance description
-                // or Sentinel for the given @InstanceRef
-                throw 'Unknown object: $id';
-              }
+              String path = id.substring(slashIndex + 1);
+              List<int> dotted = path.split(".").map(int.parse).toList();
+              int localFrame = dotted.first;
+              int localSlot = dotted[1];
+              List<int> fieldAccesses = dotted.skip(2).toList();
+              RemoteObject remoteObject = await vmContext.processLocalStructure(
+                  localFrame, localSlot,
+                  fieldAccesses: fieldAccesses);
+              sendResult(instanceDesc(remoteObject, id));
               break;
             default:
               throw "Unsupported object type $id";
@@ -525,7 +639,7 @@ class DebugConnection implements DebugListener {
           List frames = [];
           int index = 0;
           for (BackTraceFrame frame in backTrace.frames) {
-            frames.add(frameDesc(frame, index));
+            frames.add(await frameDesc(frame, index));
             index++;
           }
 
@@ -710,7 +824,7 @@ class DebugConnection implements DebugListener {
 
   @override
   pauseBreakpoint(
-      int processId, BackTraceFrame topFrame, Breakpoint breakpoint) {
+      int processId, BackTraceFrame topFrame, Breakpoint breakpoint) async {
     //TODO(danrubel): are there any other breakpoints
     // at which we are currently paused for a PauseBreakpoint event?
     List<Breakpoint> pauseBreakpoints = <Breakpoint>[];
@@ -720,7 +834,7 @@ class DebugConnection implements DebugListener {
       "kind": "PauseBreakpoint",
       "isolate": isolateRef(processId),
       "timestamp": new DateTime.now().millisecondsSinceEpoch,
-      "topFrame": frameDesc(topFrame, 0),
+      "topFrame": await frameDesc(topFrame, 0),
       "atAsyncSuspension": false,
       "breakpoint": breakpointDesc(breakpoint),
       "pauseBreakpoints":
@@ -731,13 +845,14 @@ class DebugConnection implements DebugListener {
   }
 
   @override
-  pauseException(int processId, BackTraceFrame topFrame, RemoteObject thrown) {
+  pauseException(
+      int processId, BackTraceFrame topFrame, RemoteObject thrown) async {
     Map event = {
       "type": "Event",
       "kind": "PauseException",
       "isolate": isolateRef(processId),
       "timestamp": new DateTime.now().millisecondsSinceEpoch,
-      "topFrame": frameDesc(topFrame, 0),
+      "topFrame": await frameDesc(topFrame, 0),
       "atAsyncSuspension": false,
       // TODO(sigurdm): pass thrown as an instance.
     };
@@ -750,13 +865,13 @@ class DebugConnection implements DebugListener {
   }
 
   @override
-  pauseInterrupted(int processId, BackTraceFrame topFrame) {
+  pauseInterrupted(int processId, BackTraceFrame topFrame) async {
     Map event = {
       "type": "Event",
       "kind": "PauseInterrupted",
       "isolate": isolateRef(processId),
       "timestamp": new DateTime.now().millisecondsSinceEpoch,
-      "topFrame": frameDesc(topFrame, 0),
+      "topFrame": await frameDesc(topFrame, 0),
       "atAsyncSuspension": false,
     };
     lastPauseEvent = event;
@@ -808,7 +923,7 @@ class DebugConnection implements DebugListener {
   }
 
   @override
-  resume(int processId) {
+  resume(int processId) async {
     Map event = {
       "type": "Event",
       "kind": "Resume",
@@ -817,7 +932,7 @@ class DebugConnection implements DebugListener {
     };
     BackTraceFrame topFrame = vmContext.debugState.topFrame;
     if (topFrame != null) {
-      event["topFrame"] = frameDesc(vmContext.debugState.topFrame, 0);
+      event["topFrame"] = await frameDesc(vmContext.debugState.topFrame, 0);
     }
     lastPauseEvent = event;
     streamNotify("Debug", event);