3 files changed, 31 insertions, 22 deletions

diff --git a/web/react/components/navbar_dropdown.jsx b/web/react/components/navbar_dropdown.jsx
index f43bdffdf..029b9c137 100644
--- a/web/react/components/navbar_dropdown.jsx
+++ b/web/react/components/navbar_dropdown.jsx
@@ -11,23 +11,15 @@ var AboutBuildModal = require('./about_build_modal.jsx');
 var Constants = require('../utils/constants.jsx');
 
 function getStateFromStores() {
-    let teams = [];
-    let teamsObject = UserStore.getTeams();
-    for (let teamId in teamsObject) {
+    const teams = [];
+    const teamsObject = UserStore.getTeams();
+    for (const teamId in teamsObject) {
         if (teamsObject.hasOwnProperty(teamId)) {
             teams.push(teamsObject[teamId]);
         }
     }
-    teams.sort(function sortByDisplayName(teamA, teamB) {
-        let teamADisplayName = teamA.display_name.toLowerCase();
-        let teamBDisplayName = teamB.display_name.toLowerCase();
-        if (teamADisplayName < teamBDisplayName) {
-            return -1;
-        } else if (teamADisplayName > teamBDisplayName) {
-            return 1;
-        }
-        return 0;
-    });
+
+    teams.sort(Utils.sortByDisplayName);
     return {teams};
 }
 
diff --git a/web/react/stores/channel_store.jsx b/web/react/stores/channel_store.jsx
index d1f548d50..cc0d0d14b 100644
--- a/web/react/stores/channel_store.jsx
+++ b/web/react/stores/channel_store.jsx
@@ -4,6 +4,7 @@
 var AppDispatcher = require('../dispatcher/app_dispatcher.jsx');
 var EventEmitter = require('events').EventEmitter;
 
+var Utils;
 var Constants = require('../utils/constants.jsx');
 var ActionTypes = Constants.ActionTypes;
 
@@ -183,16 +184,11 @@ class ChannelStoreClass extends EventEmitter {
             channels.push(channel);
         }
 
-        channels.sort(function chanSort(a, b) {
-            if (a.display_name.toLowerCase() < b.display_name.toLowerCase()) {
-                return -1;
-            }
-            if (a.display_name.toLowerCase() > b.display_name.toLowerCase()) {
-                return 1;
-            }
-            return 0;
-        });
+        if (!Utils) {
+            Utils = require('../utils/utils.jsx'); //eslint-disable-line global-require
+        }
 
+        channels.sort(Utils.sortByDisplayName);
         this.pStoreChannels(channels);
     }
     pStoreChannels(channels) {
diff --git a/web/react/utils/utils.jsx b/web/react/utils/utils.jsx
index c82bd1065..e8d34dccd 100644
--- a/web/react/utils/utils.jsx
+++ b/web/react/utils/utils.jsx
@@ -1104,3 +1104,24 @@ export function openDirectChannelToUser(user, successCb, errorCb) {
         );
     }
 }
+
+// Use when sorting multiple channels or teams by their `display_name` field
+export function sortByDisplayName(a, b) {
+    let aDisplayName = '';
+    let bDisplayName = '';
+
+    if (a && a.display_name) {
+        aDisplayName = a.display_name.toLowerCase();
+    }
+    if (b && b.display_name) {
+        bDisplayName = b.display_name.toLowerCase();
+    }
+
+    if (aDisplayName < bDisplayName) {
+        return -1;
+    }
+    if (aDisplayName > bDisplayName) {
+        return 1;
+    }
+    return 0;
+}