add JsArray and JsObject.asJsMap()

sdk/lib/js/dart2js/js_dart2js.dart

Index: sdk/lib/js/dart2js/js_dart2js.dart
diff --git a/sdk/lib/js/dart2js/js_dart2js.dart b/sdk/lib/js/dart2js/js_dart2js.dart
index 7f806b73f3744794eeca4b725e61093b6cf12008..7fd2726d9ac560f81cfe47ab72884fd48f261721 100644
--- a/sdk/lib/js/dart2js/js_dart2js.dart
+++ b/sdk/lib/js/dart2js/js_dart2js.dart
@@ -4,6 +4,7 @@
 
 library dart.js;
 
+import 'dart:collection' show ListMixin, Maps;
 import 'dart:_foreign_helper' show JS;
 import 'dart:_js_helper' show convertDartClosureToJS;
 
@@ -101,7 +102,7 @@ return ret;
 })()''', constr, constr, args));
   }
 
-  factory JsObject._json(data) => new JsObject._fromJs(_convertDataTree(data));
+  factory JsObject._json(data) => _convertToDart(_convertDataTree(data));
 
   static _convertDataTree(data) {
     if (data is Map) {
@@ -154,6 +155,8 @@ return ret;
       _convertToDart(JS('=Object', '#[#].apply(#, #)', _convertToJS(this), name,
           _convertToJS(this),
           args == null ? null : args.map(_convertToJS).toList()));
+
+  Map<String, dynamic> asDartMap() => new _JsObjectAsMap(this);
 }
 
 class JsFunction extends JsObject implements Serializable<JsFunction> {
@@ -164,6 +167,90 @@ class JsFunction extends JsObject implements Serializable<JsFunction> {
           args == null ? null : args.map(_convertToJS).toList()));
 }
 
+/// A [JsObject] subtype for JavaScript arrays.
+class JsArray extends JsObject with ListMixin {
+  JsArray._fromJs(jsObject) : super._fromJs(jsObject);
+
+  // methods to implement for ListMixin
+
+  int get length => super['length'];
+  void set length(int length) { super['length'] = length; }
+  operator [](index) {
+    if (index is int && (index < 0 || index >= this.length)) {
+      throw new RangeError.value(index);
+    }
+    return super[index];
+  }
+  void operator []=(index, value) {
+    if (index is int && (index < 0 || index >= this.length)) {
+      throw new RangeError.value(index);
+    }
+    super[index] = value;
+  }
+
+  // overriden methods for better performance
+
+  void add(value) { callMethod('push', [value]); }
+  void addAll(Iterable iterable) { callMethod('push', iterable.toList()); }
+  void sort([int compare(a, b)]) {
+    final sortedList = toList()..sort(compare);
+    setRange(0, sortedList.length, sortedList);
+  }
+  void insert(int index, element) {
+    callMethod('splice', [index, 0, element]);
+  }
+  removeAt(int index) {
+    if (index < 0 || index >= this.length) throw new RangeError.value(index);
+    return callMethod('splice', [index, 1])[0];
+  }
+  removeLast() => callMethod('pop');
+  void setRange(int start, int length, List from,
+                              [int startFrom = 0]) {
+    final args = [start, length];
+    for(int i = startFrom; i < startFrom + length; i++) {
+      args.add(from[i]);
+    }
+    callMethod('splice', args);
+  }
+  void removeRange(int start, int end) {
+    callMethod('splice', [start, end - start]);
+  }
+}
+
+class _JsObjectAsMap implements Map<String, dynamic> {
+  JsObject _jsObject;
+
+  _JsObjectAsMap(this._jsObject);
+
+  operator [](String key) => _jsObject[key];
+  void operator []=(String key, value) {
+    _jsObject[key] = value;
+  }
+  remove(String key) {
+    final value = this[key];
+    _jsObject.deleteProperty(key);
+    return value;
+  }
+  Iterable<String> get keys =>
+      context['Object'].callMethod('keys', [_jsObject]);
+
+  // use Maps to implement functions
+  bool containsValue(value) => Maps.containsValue(this, value);
+  bool containsKey(String key) => Maps.containsKey(this, key);
+  putIfAbsent(String key, ifAbsent()) => Maps.putIfAbsent(this, key, ifAbsent);
+  void addAll(Map<String, dynamic> other) {
+    if (other != null) {
+      other.forEach((k,v) => this[k] = v);
+    }
+  }
+  void clear() => Maps.clear(this);
+  void forEach(void f(String key, value)) => Maps.forEach(this, f);
+  Iterable get values => Maps.getValues(this);
+  int get length => Maps.length(this);
+  bool get isEmpty => Maps.isEmpty(this);
+  bool get isNotEmpty => Maps.isNotEmpty(this);
+}
+
 abstract class Serializable<T> {
   T toJs();
 }
@@ -179,6 +266,10 @@ dynamic _convertToJS(dynamic o) {
     return _convertToJS(o.toJs());
   } else if (o is Function) {
     return _convertToJS(new Callback(o));
+  } else if (o is Map) {
+    return _convertToJS(jsify(o));
+  } else if (o is Iterable) {
+    return _convertToJS(jsify(o));
   } else {
     return JS('=Object', 'new DartProxy(#)', o);
   }
@@ -192,10 +283,12 @@ dynamic _convertToDart(dynamic o) {
       JS('bool', 'typeof # == "boolean" || # instanceof Boolean', o, o)) {
     return o;
   } else if (JS('bool', '# instanceof Function', o)) {
-    return new JsFunction._fromJs(JS('=Object', '#', o));
+    return new JsFunction._fromJs(JS('var', '#', o));
+  } else if (JS('bool', '# instanceof Array', o)) {
+    return new JsArray._fromJs(JS('var', '#', o));
   } else if (JS('bool', '# instanceof DartProxy', o)) {
     return JS('var', '#.o', o);
   } else {
-    return new JsObject._fromJs(JS('=Object', '#', o));
+    return new JsObject._fromJs(JS('var', '#', o));
   }
 }