diff --git a/src/pane.coffee b/src/pane.coffee
index 76d83a175..c19eb26d4 100644
--- a/src/pane.coffee
+++ b/src/pane.coffee
@@ -677,7 +677,7 @@ class Pane extends Model
     true
 
   handleSaveError: (error) ->
-    if error.code is 'EISDIR' or error.message?.endsWith('is a directory')
+    if error.code is 'EISDIR' or error.message?.endsWith?('is a directory')
       atom.notifications.addWarning("Unable to save file: #{error.message}")
     else if error.code is 'EACCES' and error.path?
       atom.notifications.addWarning("Unable to save file: Permission denied '#{error.path}'")