From 63cfb82ca7b6366a3e9da7fd84383805a4c19bc5 Mon Sep 17 00:00:00 2001
From: Sebastian McKenzie <sebmck@gmail.com>
Date: Mon, 5 Oct 2015 16:34:40 +0100
Subject: [PATCH] clean up mergeSourceMap method - closes #2479

---
 packages/babel-core/src/transformation/file/index.js | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/packages/babel-core/src/transformation/file/index.js b/packages/babel-core/src/transformation/file/index.js
index e6c69ca1cd..731f62c5a8 100644
--- a/packages/babel-core/src/transformation/file/index.js
+++ b/packages/babel-core/src/transformation/file/index.js
@@ -417,13 +417,9 @@ export default class File extends Store {
   }
 
   mergeSourceMap(map: Object) {
-    let opts = this.opts;
-
-    let inputMap = opts.inputSourceMap;
+    let inputMap = this.opts.inputSourceMap;
 
     if (inputMap) {
-      map.sources[0] = inputMap.file;
-
       let inputMapConsumer   = new sourceMap.SourceMapConsumer(inputMap);
       let outputMapConsumer  = new sourceMap.SourceMapConsumer(map);
       let outputMapGenerator = sourceMap.SourceMapGenerator.fromSourceMap(outputMapConsumer);
@@ -433,9 +429,9 @@ export default class File extends Store {
       mergedMap.sources = inputMap.sources;
       mergedMap.file    = inputMap.file;
       return mergedMap;
+    } else {
+      return map;
     }
-
-    return map;
   }
 
   getModuleFormatter(type: string) {