feat($route): add reloadOnSearch route param to avoid reloads

In order to avoid unnecesary route reloads when just hashSearch part
of the url changes, it is now possible to disable this behavior by
setting reloadOnSearch param of the route declaration to false.

Closes #354

Author: IgorMinar

src/service/route.js

@@ -68,6 +68,8 @@ angularServiceInject('$route', function($location) {
       matcher = switchRouteMatcher,
       parentScope = this,
       dirty = 0,
+      lastHashPath,
+      lastRouteParams,
       $route = {
         routes: routes,
 
@@ -136,6 +138,18 @@ angularServiceInject('$route', function($location) {
          *      The custom `redirectTo` function is expected to return a string which will be used
          *      to update `$location.hash`.
          *
+         *    - `[reloadOnSearch=true]` - {boolean=} - reload route when $location.hashSearch
+         *      changes. If this option is disabled, you should set up a $watch to be notified of
+         *      param (hashSearch) changes as follows:
+         *
+         *            function MyCtrl($route) {
+         *              this.$watch(function() {
+         *                return $route.current.params;
+         *              }, function(scope, params) {
+         *                //do stuff with params
+         *              });
+         *            }
+         *
          * @returns {Object} route object
          *
          * @description
@@ -144,8 +158,8 @@ angularServiceInject('$route', function($location) {
         when:function (path, params) {
           if (isUndefined(path)) return routes; //TODO(im): remove - not needed!
           var route = routes[path];
-          if (!route) route = routes[path] = {};
-          if (params) extend(route, params);
+          if (!route) route = routes[path] = {reloadOnSearch: true};
+          if (params) extend(route, params); //TODO(im): what the heck? merge two route definitions?
           dirty++;
           return route;
         },
@@ -209,9 +223,18 @@ angularServiceInject('$route', function($location) {
   function updateRoute(){
     var selectedRoute, pathParams, segmentMatch, key, redir;
 
-    if ($route.current && $route.current.scope) {
-      $route.current.scope.$destroy();
+    if ($route.current) {
+      if (!$route.current.reloadOnSearch && (lastHashPath == $location.hashPath)) {
+        $route.current.params = extend($location.hashSearch, lastRouteParams);
+        return;
+      }
+
+      if ($route.current.scope) {
+        $route.current.scope.$destroy();
+      }
     }
+
+    lastHashPath = $location.hashPath;
     $route.current = null;
     // Match a route
     forEach(routes, function(rParams, rPath) {
@@ -255,19 +278,20 @@ angularServiceInject('$route', function($location) {
 
       $route.current = extend({}, selectedRoute);
       $route.current.params = extend({}, $location.hashSearch, pathParams);
+      lastRouteParams = pathParams;
     }
 
     //fire onChange callbacks
     forEach(onChange, parentScope.$eval, parentScope);
 
-    // Create the scope if we have mtched a route
+    // Create the scope if we have matched 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']);

test/service/routeSpec.js

@@ -260,4 +260,139 @@ describe('$route', function() {
       }
     });
   });
+
+
+  describe('reloadOnSearch', function() {
+    it('should reload a route when reloadOnSearch is enabled and hashSearch changes', function() {
+      var scope = angular.scope(),
+          $location = scope.$service('$location'),
+          $route = scope.$service('$route'),
+          reloaded = jasmine.createSpy('route reload');
+
+      $route.when('/foo', {controller: FooCtrl});
+      $route.onChange(reloaded);
+
+      function FooCtrl() {
+        reloaded();
+      }
+
+      $location.updateHash('/foo');
+      scope.$digest();
+      expect(reloaded).toHaveBeenCalled();
+      reloaded.reset();
+
+      // trigger reload
+      $location.hashSearch.foo = 'bar';
+      scope.$digest();
+      expect(reloaded).toHaveBeenCalled();
+    });
+
+
+    it('should not reload a route when reloadOnSearch is disabled and only hashSearch changes',
+        function() {
+      var scope = angular.scope(),
+          $location = scope.$service('$location'),
+          $route = scope.$service('$route'),
+          reloaded = jasmine.createSpy('route reload');
+
+      $route.when('/foo', {controller: FooCtrl, reloadOnSearch: false});
+      $route.onChange(reloaded);
+
+      function FooCtrl() {
+        reloaded();
+      }
+
+      expect(reloaded).not.toHaveBeenCalled();
+
+      $location.updateHash('/foo');
+      scope.$digest();
+      expect(reloaded).toHaveBeenCalled();
+      reloaded.reset();
+
+      // don't trigger reload
+      $location.hashSearch.foo = 'bar';
+      scope.$digest();
+      expect(reloaded).not.toHaveBeenCalled();
+    });
+
+
+    it('should reload reloadOnSearch route when url differs only in route path param', function() {
+      var scope = angular.scope(),
+          $location = scope.$service('$location'),
+          $route = scope.$service('$route'),
+          reloaded = jasmine.createSpy('routeReload'),
+          onRouteChange = jasmine.createSpy('onRouteChange');
+
+      $route.when('/foo/:fooId', {controller: FooCtrl, reloadOnSearch: false});
+      $route.onChange(onRouteChange);
+
+      function FooCtrl() {
+        reloaded();
+      }
+
+      expect(reloaded).not.toHaveBeenCalled();
+      expect(onRouteChange).not.toHaveBeenCalled();
+
+      $location.updateHash('/foo/aaa');
+      scope.$digest();
+      expect(reloaded).toHaveBeenCalled();
+      expect(onRouteChange).toHaveBeenCalled();
+      reloaded.reset();
+      onRouteChange.reset();
+
+      $location.updateHash('/foo/bbb');
+      scope.$digest();
+      expect(reloaded).toHaveBeenCalled();
+      expect(onRouteChange).toHaveBeenCalled();
+      reloaded.reset();
+      onRouteChange.reset();
+
+      $location.hashSearch.foo = 'bar';
+      scope.$digest();
+      expect(reloaded).not.toHaveBeenCalled();
+      expect(onRouteChange).not.toHaveBeenCalled();
+    });
+
+
+    it('should update route params when reloadOnSearch is disabled and hashSearch', function() {
+      var scope = angular.scope(),
+          $location = scope.$service('$location'),
+          $route = scope.$service('$route'),
+          routeParams = jasmine.createSpy('routeParams');
+
+      $route.when('/foo', {controller: FooCtrl});
+      $route.when('/bar/:barId', {controller: FooCtrl, reloadOnSearch: false});
+
+      function FooCtrl() {
+        this.$watch(function() {
+          return $route.current.params;
+        }, function(scope, value) {
+          routeParams(value);
+        });
+      }
+
+      expect(routeParams).not.toHaveBeenCalled();
+
+      $location.updateHash('/foo');
+      scope.$digest();
+      expect(routeParams).toHaveBeenCalledWith({});
+      routeParams.reset();
+
+      // trigger reload
+      $location.hashSearch.foo = 'bar';
+      scope.$digest();
+      expect(routeParams).toHaveBeenCalledWith({foo: 'bar'});
+      routeParams.reset();
+
+      $location.updateHash('/bar/123');
+      scope.$digest();
+      expect(routeParams).toHaveBeenCalledWith({barId: '123'});
+      routeParams.reset();
+
+      // don't trigger reload
+      $location.hashSearch.foo = 'bar';
+      scope.$digest();
+      expect(routeParams).toHaveBeenCalledWith({barId: '123', foo: 'bar'});
+    });
+  });
 });