Give fields a model class in the service library.

runtime/bin/vmservice/observatory/lib/src/service/object.dart

 // Copyright (c) 2014, 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.
 
 part of service;
 
 /// A [ServiceObject] is an object known to the VM service and is tied
 /// to an owning [Isolate].
 abstract class ServiceObject extends Observable {
   static int LexicalSortName(ServiceObject o1, ServiceObject o2) {
@@ skipping 124 matching lines @@
         break;
       case 'Context':
         obj = new Context._empty(owner);
         break;
       case 'Counter':
         obj = new ServiceMetric._empty(owner);
         break;
       case 'Error':
         obj = new DartError._empty(owner);
         break;
+      case 'Field':
+        obj = new Field._empty(owner);
+        break;
       case 'Function':
         obj = new ServiceFunction._empty(owner);
         break;
       case 'Gauge':
         obj = new ServiceMetric._empty(owner);
         break;
       case 'Isolate':
         obj = new Isolate._empty(owner.vm);
         break;
       case 'Library':
@@ skipping 1169 matching lines @@
     return 'ServiceEvent of type $eventType with '
         '${data == null ? 0 : data.lengthInBytes} bytes of binary data';
   }
 }
 
 class Library extends ServiceObject with Coverage {
   @observable String url;
   @reflectable final imports = new ObservableList<Library>();
   @reflectable final scripts = new ObservableList<Script>();
   @reflectable final classes = new ObservableList<Class>();
-  @reflectable final variables = new ObservableList<ServiceMap>();
+  @reflectable final variables = new ObservableList<Field>();
   @reflectable final functions = new ObservableList<ServiceFunction>();
 
   bool get canCache => true;
   bool get immutable => false;
 
   Library._empty(ServiceObjectOwner owner) : super._empty(owner);
 
   void _update(ObservableMap map, bool mapIsRef) {
     url = map['url'];
     var shortUrl = url;
@@ skipping 80 matching lines @@
   @observable int endTokenPos;
 
   @observable ServiceMap error;
 
   final Allocations newSpace = new Allocations();
   final Allocations oldSpace = new Allocations();
   final AllocationCount promotedByLastNewGC = new AllocationCount();
 
   bool get hasNoAllocations => newSpace.empty && oldSpace.empty;
 
-  @reflectable final fields = new ObservableList<ServiceMap>();
+  @reflectable final fields = new ObservableList<Field>();
   @reflectable final functions = new ObservableList<ServiceFunction>();
 
   @observable Class superclass;
   @reflectable final interfaces = new ObservableList<Class>();
   @reflectable final subclasses = new ObservableList<Class>();
 
   bool get canCache => true;
   bool get immutable => false;
 
   Class._empty(ServiceObjectOwner owner) : super._empty(owner);
@@ skipping 263 matching lines @@
       qualifiedName = (owningClass != null) ?
           "${owningClass.name}.${name}" :
           name;
     } else {
       qualifiedName = "${parent.qualifiedName}.${name}";
     }
 
   }
 }
 
+
+class Field extends ServiceObject {
+  @observable var /* Library or Class */ owner;

[turnidge, 2014/09/11 16:48:38]

var -> ServiceObject?

Can you use types instead of 'var' for these fields?

[rmacnak, 2014/09/11 17:25:59]

It's better to use dynamic for a union type; otherwise you get a bunch of
spurious analyzer warnings trying use either methods of Library or Class.  Added
types for the other fields though.

+  @observable var declaredType;
+  @observable bool isStatic;
+  @observable bool isFinal;
+  @observable bool isConst;
+  @observable var value;
+  @observable var name;
+  @observable var vmName;
+
+  @observable var guardNullable;
+  @observable var guardClass;
+  @observable var guardLength;
+  @observable var script;
+  @observable var tokenPos;
+
+  Field._empty(ServiceObjectOwner owner) : super._empty(owner);
+
+  void _update(ObservableMap map, bool mapIsRef) {
+    // Extract full properties.
+    _upgradeCollection(map, isolate);
+
+    name = map['name'];
+    vmName = (map.containsKey('vmName') ? map['vmName'] : name);
+    owner = map['owner'];
+    declaredType = map['declaredType'];
+    isStatic = map['static'];
+    isFinal = map['final'];
+    isConst = map['const'];
+    value = map['value'];
+
+    if (mapIsRef) {
+      return;
+    }
+
+    guardNullable = map['guardNullable'];
+    guardClass = map['guardClass'];
+    guardLength = map['guardLength'];
+    script = map['script'];
+    tokenPos = map['tokenPos'];
+
+    _loaded = true;
+  }
+
+  String toString() => 'Field(${owner.name}.$name)';
+}
+
+
 class ScriptLine extends Observable {
   final Script script;
   final int line;
   final String text;
   @observable int hits;
   @observable ServiceMap bpt;
   @observable bool possibleBpt = true;
 
   static bool _isTrivialToken(String token) {
     if (token == 'else') {
@@ skipping 938 matching lines @@
     var v = list[i];
     if ((v is ObservableMap) && _isServiceMap(v)) {
       list[i] = owner.getFromMap(v);
     } else if (v is ObservableList) {
       _upgradeObservableList(v, owner);
     } else if (v is ObservableMap) {
       _upgradeObservableMap(v, owner);
     }
   }
 }