From 7e23f3e4ef9ad52eb146de97fd2b18a739f77ac9 Mon Sep 17 00:00:00 2001
From: Joel Marcey <joelm@fb.com>
Date: Fri, 20 Oct 2017 15:19:13 -0700
Subject: [PATCH] Avoid `null` enabledLanguages when there is no languages.js
 file (#155)

```
var enabledLanguages = languages.filter(function (lang) {
                                  ^

TypeError: Cannot read property 'filter' of null
    at module.exports
```
---
 lib/server/sitemap.js | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/lib/server/sitemap.js b/lib/server/sitemap.js
index 1c036271e5..592ae0fe5d 100644
--- a/lib/server/sitemap.js
+++ b/lib/server/sitemap.js
@@ -43,16 +43,22 @@ module.exports = function(callback) {
 
   let files = glob.sync(CWD + "/pages/**/*.js");
 
-  let languages = null;
+  // English-only is the default.
+  let enabledLanguages = [{
+    enabled: true,
+    name: "English",
+    tag: "en"
+  }];
 
+  // If we have a languages.js file, get all the enabled languages in there
   if (fs.existsSync(CWD + "/languages.js")) {
-    languages = require(CWD + "/languages.js");
+    let languages = require(CWD + "/languages.js");
+    enabledLanguages = languages.filter(lang => {
+      return lang.enabled == true;
+    });
   }
 
-  let enabledLanguages = languages.filter(lang => {
-    return lang.enabled == true;
-  });
-
+  // create a url mapping to all the enabled languages files
   files.map(file => {
     enabledLanguages.map(lang => {
       let url = file.split("/pages/en")[1];