Only add .coffee to extensions if it was present before

1 files changed, 7 insertions, 2 deletions

diff --git a/lib/moduleEnv.js b/lib/moduleEnv.js
index 074b5f3..239fecd 100644
--- a/lib/moduleEnv.js
+++ b/lib/moduleEnv.js
@@ -47,12 +47,17 @@ function requireProxy(path) {
 }
 
 function registerExtensions() {
-    originalExtensions.coffee = require.extensions[".coffee"];
+    var originalCoffeeExtension = require.extensions[".coffee"];
+    if (originalCoffeeExtension) {
+        originalExtensions.coffee = originalCoffeeExtension;
+    }
     require.extensions[".coffee"] = coffeeExtension;
 }
 
 function restoreExtensions() {
-    require.extensions[".coffee"] = originalExtensions.coffee;
+    if ("coffee" in originalExtensions) {
+        require.extensions[".coffee"] = originalExtensions.coffee;
+    }
 }
 
 function coffeeExtension(module, filename) {