Only save pending updates for annotations in the focused group

Since we discard all pending updates and deletions when switching
groups, discard create/update notifications about annotations in
unfocused groups as soon as we receive them.

This fixes the issue where the 'Apply Update' badge counted updates
from other groups, with the result that clicking the badge did not
show any changes.

h/static/scripts/streamer.js

@@ -51,16 +51,17 @@ function Streamer($rootScope, annotationMapper, features, groups, session, setti
     var action = message.options.action;
     var annotations = message.payload;
 
-    if (annotations.length === 0) {
-      return;
-    }
-
     switch (action) {
     case 'create':
     case 'update':
     case 'past':
       annotations.forEach(function (ann) {
-        pendingUpdates[ann.id] = ann;
+        // Only include annotations from the focused group, since we reload all
+        // annotations and discard pending updates and deletions when switching
+        // groups
+        if (ann.group === groups.focused().id) {
+          pendingUpdates[ann.id] = ann;
+        }
       });
       break;
     case 'delete':
@@ -173,16 +174,17 @@ function Streamer($rootScope, annotationMapper, features, groups, session, setti
   };
 
   function applyPendingUpdates() {
-    var updates = Object.values(pendingUpdates).filter(function (ann) {
-      // Ignore updates to annotations that are not in the focused group
-      return ann.group === groups.focused().id;
-    });
+    var updates = Object.values(pendingUpdates);
     var deletions = Object.keys(pendingDeletions).map(function (id) {
       return {id: id};
     });
 
-    annotationMapper.loadAnnotations(updates);
-    annotationMapper.unloadAnnotations(deletions);
+    if (updates.length) {
+      annotationMapper.loadAnnotations(updates);
+    }
+    if (deletions.length) {
+      annotationMapper.unloadAnnotations(deletions);
+    }
 
     pendingUpdates = {};
     pendingDeletions = {};

h/static/scripts/test/streamer-test.js

@@ -35,7 +35,6 @@ var fixtures = {
     },
     payload: [{
       id: 'an-id',
-      group: 'public',
     }],
   },
 };
@@ -109,9 +108,7 @@ describe('Streamer', function () {
     };
 
     fakeGroups = {
-      focused: function () {
-        return {id: 'public'};
-      },
+      focused: sinon.stub().returns({id: 'public'}),
     };
 
     fakeSession = {
@@ -200,6 +197,12 @@ describe('Streamer', function () {
         fakeWebSocket.notify(fixtures.deleteNotification);
         assert.ok(fakeAnnotationMapper.unloadAnnotations.calledOnce);
       });
+
+      it('ignores notifications about annotations in unfocused groups', function () {
+        fakeGroups.focused.returns({id: 'private'});
+        fakeWebSocket.notify(fixtures.createNotification);
+        assert.notCalled(fakeAnnotationMapper.loadAnnotations);
+      });
     });
 
     context('when realtime updates are deferred', function () {
@@ -212,6 +215,12 @@ describe('Streamer', function () {
         assert.equal(activeStreamer.countPendingUpdates(), 1);
       });
 
+      it('does not save pending updates for annotations in unfocused groups', function () {
+        fakeGroups.focused.returns({id: 'private'});
+        fakeWebSocket.notify(fixtures.createNotification);
+        assert.equal(activeStreamer.countPendingUpdates(), 0);
+      });
+
       it('saves pending deletions', function () {
         var id = fixtures.deleteNotification.payload[0].id;
         fakeWebSocket.notify(fixtures.deleteNotification);
@@ -256,13 +265,6 @@ describe('Streamer', function () {
         fixtures.createNotification.payload);
     });
 
-    it('does not apply pending updates for annotations in unfocused groups', function () {
-      fakeWebSocket.notify(fixtures.createNotification);
-      fakeGroups.focused = function () { return {id: 'private'}; };
-      activeStreamer.applyPendingUpdates();
-      assert.calledWith(fakeAnnotationMapper.loadAnnotations, []);
-    });
-
     it('applies pending deletions', function () {
       fakeWebSocket.notify(fixtures.deleteNotification);
       activeStreamer.applyPendingUpdates();