diff --git a/lib/empty/index.js b/lib/empty/index.js
index 23172bdc..a17cbae1 100644
--- a/lib/empty/index.js
+++ b/lib/empty/index.js
@@ -4,6 +4,7 @@ var mkdir = require('../mkdirs')
 var remove = require('../remove')
 
 function emptyDir (dir, callback) {
+  callback = callback || function () {}
   fs.readdir(dir, function (err, items) {
     if (err) return mkdir.mkdirs(dir, callback)