From 4fc53119f9fa69aeb2c1656514707d8f2dd161af Mon Sep 17 00:00:00 2001
From: Matt Lewis <mattlewis92@users.noreply.github.com>
Date: Sun, 30 Apr 2017 18:51:50 +0100
Subject: [PATCH] fix: don't throw when there are no sources as part of the
 sourcemap

Closes #15
---
 src/util.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util.js b/src/util.js
index 8a1b8e5..2558de8 100644
--- a/src/util.js
+++ b/src/util.js
@@ -19,7 +19,7 @@ function fixWebpackFilePath(filePath) {
 
 function fixWebpackSourcePaths(sourceMap) {
   return Object.assign({}, sourceMap, {
-    sources: sourceMap.sources.map(source => {
+    sources: (sourceMap.sources || []).map(source => {
       source = fixWebpackFilePath(source);
       if (sourceMap.sourceRoot && source.startsWith(sourceMap.sourceRoot)) {
         source = source.replace(sourceMap.sourceRoot, '');