From 2738baac01810c7188274c0d3cc84f8522da88cd Mon Sep 17 00:00:00 2001
From: Brandon Payton <brandon@happycode.net>
Date: Mon, 5 Feb 2018 02:07:58 -0700
Subject: [PATCH] Make preprocessor optional again (#172)

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

diff --git a/lib/options.js b/lib/options.js
index 75010e1..6497e56 100644
--- a/lib/options.js
+++ b/lib/options.js
@@ -74,7 +74,7 @@ function parseAssetsPath(assets) {
 }
 
 function parsePreprocessorArg(preprocessor) {
-  if(!_.startsWith(preprocessor, '/')) {
+  if(preprocessor && !_.startsWith(preprocessor, '/')) {
     preprocessor = path.join(process.cwd(), preprocessor);
   }
   return preprocessor ? require(preprocessor) : _.identity;