Remove digest triggering in AnnotationUISync

This is no longer needed following the addition of middleware to the
Redux store which triggers a digest following a UI state change if
necessary.

Also add a comment in the WebSocket code that we will be able to remove
the $apply() call once session state has been moved to the Redux store.

h/static/scripts/annotation-ui-sync.js

@@ -58,20 +58,10 @@ function AnnotationUISync($rootScope, $window, annotationUI, bridge) {
     }
   };
 
-  // Because the channel events are all outside of the angular framework we
-  // need to inform Angular that it needs to re-check it's state and re-draw
-  // any UI that may have been affected by the handlers.
-  var ensureDigest = function (fn) {
-    return function () {
-      fn.apply(this, arguments);
-      $rootScope.$digest();
-    };
-  };
-
   for (var channel in channelListeners) {
     if (Object.prototype.hasOwnProperty.call(channelListeners, channel)) {
       var listener = channelListeners[channel];
-      bridge.on(channel, ensureDigest(listener));
+      bridge.on(channel, listener);
     }
   }
 

h/static/scripts/streamer.js

@@ -128,9 +128,12 @@ function connect($rootScope, annotationMapper, groups, session, settings) {
   });
 
   socket.on('message', function (event) {
-    // wrap message dispatches in $rootScope.$apply() so that
+    // Wrap message dispatches in $rootScope.$apply() so that
     // scope watches on app state affected by the received message
     // are updated
+    //
+    // Note: The use of $apply() here will no longer be needed once session
+    // state is moved to the Redux store in `annotationUI`.
     $rootScope.$apply(function () {
       var message = JSON.parse(event.data);
       if (!message) {

h/static/scripts/test/annotation-ui-sync-test.js

@@ -6,7 +6,6 @@ var annotationUIFactory = require('../annotation-ui');
 
 describe('AnnotationUISync', function () {
   var sandbox = sinon.sandbox.create();
-  var $digest;
   var publish;
   var fakeBridge;
   var annotationUI;
@@ -23,7 +22,6 @@ describe('AnnotationUISync', function () {
 
   beforeEach(angular.mock.module('h'));
   beforeEach(angular.mock.inject(function (AnnotationUISync, $rootScope) {
-    $digest = sandbox.stub($rootScope, '$digest');
     var listeners = {};
     publish = function (method) {
       var args = [].slice.apply(arguments);
@@ -96,12 +94,6 @@ describe('AnnotationUISync', function () {
       publish('showAnnotations', ['tag1', 'tag-for-a-new-annotation']);
       assert.calledWith(annotationUI.selectAnnotations, ['id1']);
     });
-
-    it('triggers a digest', function () {
-      createAnnotationUISync();
-      publish('showAnnotations', ['tag1', 'tag2', 'tag3']);
-      assert.called($digest);
-    });
   });
 
   describe('on "focusAnnotations" event', function () {
@@ -114,12 +106,6 @@ describe('AnnotationUISync', function () {
         tag3: true,
       });
     });
-
-    it('triggers a digest', function () {
-      createAnnotationUISync();
-      publish('focusAnnotations', ['tag1', 'tag2', 'tag3']);
-      assert.called($digest);
-    });
   });
 
   describe('on "toggleAnnotationSelection" event', function () {
@@ -129,12 +115,6 @@ describe('AnnotationUISync', function () {
       publish('toggleAnnotationSelection', ['tag1', 'tag2', 'tag3']);
       assert.calledWith(annotationUI.toggleSelectedAnnotations, ['id1', 'id2', 'id3']);
     });
-
-    it('triggers a digest', function () {
-      createAnnotationUISync();
-      publish('toggleAnnotationSelection', ['tag1', 'tag2', 'tag3']);
-      assert.called($digest);
-    });
   });
 
   describe('on "setVisibleHighlights" event', function () {
@@ -149,11 +129,5 @@ describe('AnnotationUISync', function () {
       publish('setVisibleHighlights', true);
       assert.calledWith(fakeBridge.call, 'setVisibleHighlights', true);
     });
-
-    it('triggers a digest of the application state', function () {
-      createAnnotationUISync();
-      publish('setVisibleHighlights', true);
-      assert.called($digest);
-    });
   });
 });