Add JsArray

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 852b0dbc4ede6c4830bf080809c8aa81ae1b10d3..226cbb97300059ef0907d0cf160a757aea8cd38b 100644
--- a/sdk/lib/js/dart2js/js_dart2js.dart
+++ b/sdk/lib/js/dart2js/js_dart2js.dart
@@ -5,7 +5,7 @@
 library dart.js;
 
 import 'dart:html' show Blob, ImageData, Node;
-import 'dart:collection' show HashMap;
+import 'dart:collection' show HashMap, ListMixin;
 import 'dart:indexed_db' show KeyRange;
 import 'dart:typed_data' show TypedData;
 
@@ -29,7 +29,7 @@ _callDartFunction(callback, bool captureThis, self, List arguments) {
   if (captureThis) {
     arguments = [self]..addAll(arguments);
   }
-  var dartArgs = arguments.map(_convertToDart).toList();
+  var dartArgs = new List.from(arguments.map(_convertToDart));
   return _convertToJS(Function.apply(callback, dartArgs));
 }
 
@@ -187,7 +187,7 @@ class JsObject {
     }
     return _convertToDart(JS('', '#[#].apply(#, #)', _jsObject, name,
         _jsObject,
-        args == null ? null : args.map(_convertToJS).toList()));
+        args == null ? null : new List.from(args.map(_convertToJS))));
   }
 }
 
@@ -207,7 +207,99 @@ class JsFunction extends JsObject {
   dynamic apply(List args, { thisArg }) =>
       _convertToDart(JS('', '#.apply(#, #)', _jsObject,
           _convertToJS(thisArg),
-          args == null ? null : args.map(_convertToJS).toList()));
+          args == null ? null : new List.from(args.map(_convertToJS))));
+}
+
+/**
+ * A [List] that is stored in a JavaScript array.
+ */
+class JsArray<E> extends JsObject with ListMixin<E> {
+
+  JsArray() : super._fromJs([]);
+
+  JsArray.from(Iterable<E> other)
+      : super._fromJs([]..addAll(other.map(_convertToJS)));
+
+  JsArray._fromJs(jsObject) : super._fromJs(jsObject);
+
+  _checkIndex(int index, {bool insert: false}) {

[Jacob, 2013/10/24 21:02:09]

why not have two check index methods? one for insert and one for the regular
case?

[justinfagnani, 2013/10/26 03:26:52]

Done.

+    int length = insert ? this.length + 1 : this.length;
+    if (index is int && (index < 0 || index >= length)) {
+      throw new RangeError.range(index, 0, length);
+    }
+  }
+
+  _checkRange(int start, int end) {
+    if (start < 0 || start > this.length) {
+      throw new RangeError.range(start, 0, this.length);
+    }
+    if (end < start || end > this.length) {
+      throw new RangeError.range(end, start, this.length);
+    }
+  }
+
+  // Methods required by ListMixin
+
+  E operator [](int index) {
+    _checkIndex(index);
+    return super[index];
+  }
+
+  void operator []=(int index, E value) {
+    _checkIndex(index);
+    super[index] = value;
+  }
+
+  int get length => super['length'];
+
+  void set length(int length) { super['length'] = length; }
+
+
+  // Methods overriden for better performance
+
+  void add(E value) {
+    callMethod('push', [value]);
+  }
+
+  void addAll(Iterable<E> iterable) {
+    var list = (JS('bool', '# instanceof Array', iterable)) 
+        ? iterable
+        : new List.from(iterable);
+    callMethod('push', list);
+  }
+
+  void insert(int index, E element) {
+    _checkIndex(index, insert:true);
+    callMethod('splice', [index, 0, element]);
+  }
+
+  E removeAt(int index) {
+    _checkIndex(index);
+    return callMethod('splice', [index, 1])[0];
+  }
+
+  E removeLast() {
+    if (length == 0) throw new RangeError(-1);
+    return callMethod('pop');
+  }
+
+  void removeRange(int start, int end) {
+    _checkRange(start, end);
+    callMethod('splice', [start, end - start]);
+  }
+
+  void setRange(int start, int end, Iterable<E> iterable, [int skipCount = 0]) {
+    _checkRange(start, end);
+    int length = end - start;
+    if (length == 0) return;
+    if (skipCount < 0) throw new ArgumentError(skipCount);
+    var args = [start, length]..addAll(iterable.skip(skipCount).take(length));
+    callMethod('splice', args);
+  }
+
+  void sort([int compare(E a, E b)]) {
+    callMethod('sort', [compare]);
+  }
 }
 
 // property added to a Dart object referencing its JS-side DartObject proxy
@@ -281,6 +373,9 @@ Object _convertToDart(o) {
   } else if (JS('bool', 'typeof # == "function"', o)) {
     return _getDartProxy(o, _DART_CLOSURE_PROPERTY_NAME,
         (o) => new JsFunction._fromJs(o));
+  } else if (JS('bool', '# instanceof Array', o)) {
+    return _getDartProxy(o, _DART_OBJECT_PROPERTY_NAME,
+        (o) => new JsArray._fromJs(o));
   } else if (JS('bool', '#.constructor === DartObject', o)) {
     return JS('', '#.o', o);
   } else {