require a file name before checking for a fallback

Author: jashkenas

lib/coffee-script/command.js

@@ -96,7 +96,7 @@
         throw err;
       }
       if ((err != null ? err.code : void 0) === 'ENOENT') {
-        if (topLevel && (_ref1 = path.extname(source), __indexOf.call(coffee_exts, _ref1) < 0)) {
+        if (topLevel && source && (_ref1 = path.extname(source), __indexOf.call(coffee_exts, _ref1) < 0)) {
           source = sources[sources.indexOf(source)] = "" + source + ".coffee";
           return compilePath(source, topLevel, base);
         }

src/command.coffee

@@ -86,7 +86,7 @@ compilePath = (source, topLevel, base) ->
   fs.stat source, (err, stats) ->
     throw err if err and err.code isnt 'ENOENT'
     if err?.code is 'ENOENT'
-      if topLevel and path.extname(source) not in coffee_exts
+      if topLevel and source and path.extname(source) not in coffee_exts
         source = sources[sources.indexOf(source)] = "#{source}.coffee"
         return compilePath source, topLevel, base
       if topLevel