3 files changed, 7 insertions, 7 deletions
diff --git a/app/assets/javascripts/merge_request_tabs.js b/app/assets/javascripts/merge_request_tabs.js
index ff1416af31b..cfd10922bd0 100644
--- a/app/assets/javascripts/merge_request_tabs.js
+++ b/app/assets/javascripts/merge_request_tabs.js
@@ -120,7 +120,7 @@
           return function(data) {
             $('#diffs').html(data.html);
 
-            if (DiffNotesApp) {
+            if (typeof DiffNotesApp !== 'undefined') {
               DiffNotesApp.compileComponents();
             }
 
diff --git a/app/assets/javascripts/notes.js b/app/assets/javascripts/notes.js
index ab169d04804..fd5163bdd5b 100644
--- a/app/assets/javascripts/notes.js
+++ b/app/assets/javascripts/notes.js
@@ -300,7 +300,7 @@
         discussionContainer.append(note_html);
       }
 
-      if (DiffNotesApp) {
+      if (typeof DiffNotesApp !== 'undefined') {
         DiffNotesApp.compileComponents();
       }
 
@@ -429,7 +429,7 @@
 
       $note_li.replaceWith($html);
 
-      if (DiffNotesApp) {
+      if (typeof DiffNotesApp !== 'undefined') {
         DiffNotesApp.compileComponents();
       }
     };
@@ -593,7 +593,7 @@
 
       if (canResolve === 'false' || !form.closest('.notes_content').find('.note:not(.system-note)').length) {
         form.find('comment-and-resolve-btn').remove();
-      } else if (DiffNotesApp) {
+      } else if (typeof DiffNotesApp !== 'undefined') {
         var $commentBtn = form.find('comment-and-resolve-btn');
         $commentBtn
           .attr(':discussion-id', "'" + dataHolder.data('discussionId') + "'");
diff --git a/app/assets/javascripts/single_file_diff.js b/app/assets/javascripts/single_file_diff.js
index 9d181586b1d..b9adc5f3728 100644
--- a/app/assets/javascripts/single_file_diff.js
+++ b/app/assets/javascripts/single_file_diff.js
@@ -36,13 +36,13 @@
       if (!this.isOpen && !this.hasError) {
         this.content.hide();
         this.collapsedContent.show();
-        if (DiffNotesApp) {
+        if (typeof DiffNotesApp !== 'undefined') {
           DiffNotesApp.compileComponents();
         }
       } else if (this.content) {
         this.collapsedContent.hide();
         this.content.show();
-        if (DiffNotesApp) {
+        if (typeof DiffNotesApp !== 'undefined') {
           DiffNotesApp.compileComponents();
         }
       } else {
@@ -59,7 +59,7 @@
           if (data.html) {
             _this.content = $(data.html);
             _this.content.syntaxHighlight();
-            if (DiffNotesApp) {
+            if (typeof DiffNotesApp !== 'undefined') {
               DiffNotesApp.compileComponents();
             }
           } else {