From c68bb0a8206f0ea97f8bf31e8ad2f2e817a96486 Mon Sep 17 00:00:00 2001
From: Iskren Chernev <iskren.chernev@gmail.com>
Date: Fri, 29 Aug 2014 19:11:45 +0300
Subject: [PATCH] Fix moment().locale('ivalid-id')

---
 moment.js             | 10 +++++++---
 test/moment/locale.js | 12 ++++++++++++
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/moment.js b/moment.js
index 868206aad..3b5d65adc 100644
--- a/moment.js
+++ b/moment.js
@@ -2448,10 +2448,15 @@
         // instance.  Otherwise, it will return the locale configuration
         // variables for this instance.
         locale : function (key) {
+            var newLocaleData;
+
             if (key === undefined) {
                 return this._locale._abbr;
             } else {
-                this._locale = moment.localeData(key);
+                newLocaleData = moment.localeData(key);
+                if (newLocaleData != null) {
+                    this._locale = newLocaleData;
+                }
                 return this;
             }
         },
@@ -2462,8 +2467,7 @@
                 if (key === undefined) {
                     return this.localeData();
                 } else {
-                    this._locale = moment.localeData(key);
-                    return this;
+                    return this.locale(key);
                 }
             }
         ),
diff --git a/test/moment/locale.js b/test/moment/locale.js
index bf0bcdefb..57ecb4ae9 100644
--- a/test/moment/locale.js
+++ b/test/moment/locale.js
@@ -458,5 +458,17 @@ exports.locale = {
         test.equal(m.locale(), 'fr', 'instance locale reset to global locale');
 
         test.done();
+    },
+
+    'moment().locale with missing key doesn\'t change locale' : function (test) {
+        test.equal(moment().locale('boo').localeData(), moment.localeData(),
+                'preserve global locale in case of bad locale id');
+        test.done();
+    },
+
+    'moment().lang with missing key doesn\'t change locale' : function (test) {
+        test.equal(moment().lang('boo').localeData(), moment.localeData(),
+                'preserve global locale in case of bad locale id');
+        test.done();
     }
 };
-- 
2.47.2