From 7a12f3660270c16e239e1862b7b65a5140f3ea0f Mon Sep 17 00:00:00 2001
From: Matt Zabriskie <mzabriskie@gmail.com>
Date: Thu, 23 Jun 2016 13:59:03 -0600
Subject: [PATCH] Only use  if it's a function

---
 lib/adapters/xhr.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/adapters/xhr.js b/lib/adapters/xhr.js
index 2cfc31a..0f19802 100644
--- a/lib/adapters/xhr.js
+++ b/lib/adapters/xhr.js
@@ -143,7 +143,7 @@ module.exports = function xhrAdapter(resolve, reject, config) {
   }
 
   // Handle progress if needed
-  if (config.progress) {
+  if (typeof config.progress === 'function') {
     if (config.method === 'post' || config.method === 'put') {
       request.upload.addEventListener('progress', config.progress);
     } else if (config.method === 'get') {