feat(scope): new and improved scope implementation

- Speed improvements (about 4x on flush phase)
- Memory improvements (uses no function closures)
- Break $eval into $apply, $dispatch, $flush
- Introduced $watch and $observe

Breaks angular.equals() use === instead of ==
Breaks angular.scope() does not take parent as first argument
Breaks scope.$watch() takes scope as first argument
Breaks scope.$set(), scope.$get are removed
Breaks scope.$config is removed
Breaks $route.onChange callback has not "this" bounded

7 files changed, 54 insertions, 71 deletions

diff --git a/src/service/cookies.js b/src/service/cookies.js
index d6be1364..74e63679 100644
--- a/src/service/cookies.js
+++ b/src/service/cookies.js
@@ -28,7 +28,7 @@ angularServiceInject('$cookies', function($browser) {
       lastBrowserCookies = currentCookies;
       copy(currentCookies, lastCookies);
       copy(currentCookies, cookies);
-      if (runEval) rootScope.$eval();
+      if (runEval) rootScope.$apply();
     }
   })();
 
@@ -37,7 +37,7 @@ angularServiceInject('$cookies', function($browser) {
   //at the end of each eval, push cookies
   //TODO: this should happen before the "delayed" watches fire, because if some cookies are not
   //      strings or browser refuses to store some cookies, we update the model in the push fn.
-  this.$onEval(PRIORITY_LAST, push);
+  this.$observe(push);
 
   return cookies;
 
diff --git a/src/service/defer.js b/src/service/defer.js
index 551e8bc9..0a69912c 100644
--- a/src/service/defer.js
+++ b/src/service/defer.js
@@ -18,16 +18,11 @@
  * @param {function()} fn A function, who's execution should be deferred.
  * @param {number=} [delay=0] of milliseconds to defer the function execution.
  */
-angularServiceInject('$defer', function($browser, $exceptionHandler, $updateView) {
+angularServiceInject('$defer', function($browser) {
+  var scope = this;
   return function(fn, delay) {
     $browser.defer(function() {
-      try {
-        fn();
-      } catch(e) {
-        $exceptionHandler(e);
-      } finally {
-        $updateView();
-      }
+      scope.$apply(fn);
     }, delay);
   };
 }, ['$browser', '$exceptionHandler', '$updateView']);
diff --git a/src/service/invalidWidgets.js b/src/service/invalidWidgets.js
index b7ef0b53..7c1b2a9f 100644
--- a/src/service/invalidWidgets.js
+++ b/src/service/invalidWidgets.js
@@ -42,7 +42,7 @@ angularServiceInject("$invalidWidgets", function(){
 
 
   /* At the end of each eval removes all invalid widgets that are not part of the current DOM. */
-  this.$onEval(PRIORITY_LAST, function() {
+  this.$watch(function() {
     for(var i = 0; i < invalidWidgets.length;) {
       var widget = invalidWidgets[i];
       if (isOrphan(widget[0])) {
@@ -56,7 +56,7 @@ angularServiceInject("$invalidWidgets", function(){
 
 
   /**
-   * Traverses DOM element's (widget's) parents and considers the element to be an orphant if one of
+   * Traverses DOM element's (widget's) parents and considers the element to be an orphan if one of
    * it's parents isn't the current window.document.
    */
   function isOrphan(widget) {
diff --git a/src/service/location.js b/src/service/location.js
index 1889266e..23531140 100644
--- a/src/service/location.js
+++ b/src/service/location.js
@@ -69,18 +69,14 @@ var URL_MATCH = /^(file|ftp|http|https):\/\/(\w+:{0,1}\w*@)?([\w\.-]*)(:([0-9]+)
     </doc:example>
  */
 angularServiceInject("$location", function($browser) {
-  var scope = this,
-      location = {update:update, updateHash: updateHash},
-      lastLocation = {};
+  var location = {update: update, updateHash: updateHash};
+  var lastLocation = {}; // last state since last update().
 
-  $browser.onHashChange(function() { //register
+  $browser.onHashChange(bind(this, this.$apply, function() { //register
     update($browser.getUrl());
-    copy(location, lastLocation);
-    scope.$eval();
-  })(); //initialize
+  }))(); //initialize
 
-  this.$onEval(PRIORITY_FIRST, sync);
-  this.$onEval(PRIORITY_LAST, updateBrowser);
+  this.$watch(sync);
 
   return location;
 
@@ -94,6 +90,8 @@ angularServiceInject("$location", function($browser) {
    *
    * @description
    * Updates the location object.
+   * Does not immediately update the browser
+   * Browser is updated at the end of $flush()
    *
    * Does not immediately update the browser. Instead the browser is updated at the end of $eval()
    * cycle.
@@ -122,6 +120,8 @@ angularServiceInject("$location", function($browser) {
 
       location.href = composeHref(location);
     }
+    $browser.setUrl(location.href);
+    copy(location, lastLocation);
   }
 
   /**
@@ -188,34 +188,21 @@ angularServiceInject("$location", function($browser) {
     if (!equals(location, lastLocation)) {
       if (location.href != lastLocation.href) {
         update(location.href);
-        return;
-      }
-      if (location.hash != lastLocation.hash) {
-        var hash = parseHash(location.hash);
-        updateHash(hash.hashPath, hash.hashSearch);
       } else {
-        location.hash = composeHash(location);
-        location.href = composeHref(location);
+        if (location.hash != lastLocation.hash) {
+          var hash = parseHash(location.hash);
+          updateHash(hash.hashPath, hash.hashSearch);
+        } else {
+          location.hash = composeHash(location);
+          location.href = composeHref(location);
+        }
+        update(location.href);
       }
-      update(location.href);
     }
   }
 
 
   /**
-   * If location has changed, update the browser
-   * This method is called at the end of $eval() phase
-   */
-  function updateBrowser() {
-    sync();
-
-    if ($browser.getUrl() != location.href) {
-      $browser.setUrl(location.href);
-      copy(location, lastLocation);
-    }
-  }
-
-  /**
    * Compose href string from a location object
    *
    * @param {Object} loc The location object with all properties
diff --git a/src/service/route.js b/src/service/route.js
index 9534968a..e1d0e7be 100644
--- a/src/service/route.js
+++ b/src/service/route.js
@@ -62,7 +62,7 @@
       </doc:scenario>
     </doc:example>
  */
-angularServiceInject('$route', function(location, $updateView) {
+angularServiceInject('$route', function($location, $updateView) {
   var routes = {},
       onChange = [],
       matcher = switchRouteMatcher,
@@ -207,66 +207,67 @@ angularServiceInject('$route', function(location, $updateView) {
 
 
   function updateRoute(){
-    var childScope, routeParams, pathParams, segmentMatch, key, redir;
+    var selectedRoute, pathParams, segmentMatch, key, redir;
 
+    if ($route.current && $route.current.scope) {
+      $route.current.scope.$destroy();
+    }
     $route.current = null;
+    // Match a route
     forEach(routes, function(rParams, rPath) {
       if (!pathParams) {
-        if (pathParams = matcher(location.hashPath, rPath)) {
-          routeParams = rParams;
+        if (pathParams = matcher($location.hashPath, rPath)) {
+          selectedRoute = rParams;
         }
       }
     });
 
-    // "otherwise" fallback
-    routeParams = routeParams || routes[null];
+    // No route matched; fallback to "otherwise" route
+    selectedRoute = selectedRoute || routes[null];
 
-    if(routeParams) {
-      if (routeParams.redirectTo) {
-        if (isString(routeParams.redirectTo)) {
+    if(selectedRoute) {
+      if (selectedRoute.redirectTo) {
+        if (isString(selectedRoute.redirectTo)) {
           // interpolate the redirectTo string
           redir = {hashPath: '',
-                   hashSearch: extend({}, location.hashSearch, pathParams)};
+                   hashSearch: extend({}, $location.hashSearch, pathParams)};
 
-          forEach(routeParams.redirectTo.split(':'), function(segment, i) {
+          forEach(selectedRoute.redirectTo.split(':'), function(segment, i) {
             if (i==0) {
               redir.hashPath += segment;
             } else {
               segmentMatch = segment.match(/(\w+)(.*)/);
               key = segmentMatch[1];
-              redir.hashPath += pathParams[key] || location.hashSearch[key];
+              redir.hashPath += pathParams[key] || $location.hashSearch[key];
               redir.hashPath += segmentMatch[2] || '';
               delete redir.hashSearch[key];
             }
           });
         } else {
           // call custom redirectTo function
-          redir = {hash: routeParams.redirectTo(pathParams, location.hash, location.hashPath,
-                                                location.hashSearch)};
+          redir = {hash: selectedRoute.redirectTo(pathParams, $location.hash, $location.hashPath,
+                                                $location.hashSearch)};
         }
 
-        location.update(redir);
-        $updateView(); //TODO this is to work around the $location<=>$browser issues
+        $location.update(redir);
         return;
       }
 
-      childScope = createScope(parentScope);
-      $route.current = extend({}, routeParams, {
-        scope: childScope,
-        params: extend({}, location.hashSearch, pathParams)
-      });
+      $route.current = extend({}, selectedRoute);
+      $route.current.params = extend({}, $location.hashSearch, pathParams);
     }
 
     //fire onChange callbacks
-    forEach(onChange, parentScope.$tryEval);
+    forEach(onChange, parentScope.$eval, parentScope);
 
-    if (childScope) {
-      childScope.$become($route.current.controller);
+    // Create the scope if we have mtched a route
+    if ($route.current) {
+      $route.current.scope = parentScope.$new($route.current.controller);
     }
   }
 
 
-  this.$watch(function(){return dirty + location.hash;}, updateRoute);
+  this.$watch(function(){return dirty + $location.hash;}, updateRoute)();
 
   return $route;
 }, ['$location', '$updateView']);
diff --git a/src/service/updateView.js b/src/service/updateView.js
index 9ac7c1fb..b51e719b 100644
--- a/src/service/updateView.js
+++ b/src/service/updateView.js
@@ -35,8 +35,8 @@
  *      without angular knowledge and you may need to call '$updateView()' directly.
  *
  * Note: if you wish to update the view immediately (without delay), you can do so by calling
- * {@link angular.scope.$eval} at any time from your code:
- * <pre>scope.$root.$eval()</pre>
+ * {@link angular.scope.$apply} at any time from your code:
+ * <pre>scope.$apply()</pre>
  *
  * In unit-test mode the update is instantaneous and synchronous to simplify writing tests.
  *
@@ -47,7 +47,7 @@ function serviceUpdateViewFactory($browser){
   var scheduled;
   function update(){
     scheduled = false;
-    rootScope.$eval();
+    rootScope.$flush();
   }
   return $browser.isMock ? update : function(){
     if (!scheduled) {
diff --git a/src/service/xhr.bulk.js b/src/service/xhr.bulk.js
index d7fc7990..816336f8 100644
--- a/src/service/xhr.bulk.js
+++ b/src/service/xhr.bulk.js
@@ -82,6 +82,6 @@ angularServiceInject('$xhr.bulk', function($xhr, $error, $log){
       }
     });
   };
-  this.$onEval(PRIORITY_LAST, bulkXHR.flush);
+  this.$observe(bulkXHR.flush);
   return bulkXHR;
 }, ['$xhr', '$xhr.error', '$log']);