ng-watch directive

src/Scope.js

@@ -207,6 +207,10 @@ Scope.prototype = {
   },
 
   addWatchListener: function(watchExpression, listener) {
+    // TODO: clean me up!
+    if (!isFunction(listener)) {
+      listener = bind(this, this.compile(listener), {scope: this, self: this.state});
+    }
     var watcher = this.watchListeners[watchExpression];
     if (!watcher) {
       watcher = {listeners:[], expression:watchExpression};

src/directives.js

@@ -82,6 +82,17 @@ angularDirective("ng-repeat", function(expression, element){
   };
 }, {exclusive: true});
 
+angularDirective("ng-watch", function(expression, element){
+  var match = expression.match(/^([^.]*):(.*)$/);
+  if (!match) {
+    throw "Expecting watch expression 'ident_to_watch: watch_statement' got '"
+        + expression + "'";
+  }
+  return function(){
+    this.$watch(match[1], match[2]);
+  };
+});
+
 
 /////////////////////////////////////////
 /////////////////////////////////////////
@@ -109,17 +120,6 @@ angularDirective("action", function(expression, element){
   };
 });
 
-//ng-watch
-// <div ng-watch="$anchor.book: book=Book.get();"/>
-angularDirective("watch", function(expression, element){
-  var watches = {
-    'lhs':'rhs'
-  }; // parse
-  return function(){
-    this.$watch(watches);
-  };
-});
-
 //widget related
 //ng-validate, ng-required, ng-formatter
 //ng-error

test/directivesSpec.js

@@ -82,4 +82,16 @@ describe("directives", function(){
     });
     expect(log).toEqual("\"Expected ng-repeat in form of 'item in collection' but got 'i dont parse'.\";true;");
   });
+
+  it('should ng-watch', function(){
+    var scope = compile('<div ng-watch="i: count = count + 1" ng-init="count = 0">');
+    scope.updateView();
+    scope.updateView();
+    expect(scope.get('count')).toEqual(0);
+
+    scope.set('i', 0);
+    scope.updateView();
+    scope.updateView();
+    expect(scope.get('count')).toEqual(1);
+  });
 });