From 01f84a1fa205b3fe493cb9422cab89dfaf97997a Mon Sep 17 00:00:00 2001
From: Ash Searle <ash@hexmen.com>
Date: Tue, 11 Jul 2017 19:46:43 +0100
Subject: [PATCH] Fix moment issue #3997

---
 src/lib/moment/add-subtract.js | 8 ++++----
 src/test/moment/duration.js    | 7 +++++++
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/lib/moment/add-subtract.js b/src/lib/moment/add-subtract.js
index b9e86a69d..e758b5d46 100644
--- a/src/lib/moment/add-subtract.js
+++ b/src/lib/moment/add-subtract.js
@@ -36,14 +36,14 @@ export function addSubtract (mom, duration, isAdding, updateOffset) {
 
     updateOffset = updateOffset == null ? true : updateOffset;
 
-    if (milliseconds) {
-        mom._d.setTime(mom._d.valueOf() + milliseconds * isAdding);
+    if (months) {
+        setMonth(mom, get(mom, 'Month') + months * isAdding);
     }
     if (days) {
         set(mom, 'Date', get(mom, 'Date') + days * isAdding);
     }
-    if (months) {
-        setMonth(mom, get(mom, 'Month') + months * isAdding);
+    if (milliseconds) {
+        mom._d.setTime(mom._d.valueOf() + milliseconds * isAdding);
     }
     if (updateOffset) {
         hooks.updateOffset(mom, days || months);
diff --git a/src/test/moment/duration.js b/src/test/moment/duration.js
index c7e0ea377..624d77787 100644
--- a/src/test/moment/duration.js
+++ b/src/test/moment/duration.js
@@ -611,6 +611,13 @@ test('add', function (assert) {
     assert.equal(d.add({h: 23, m: 59})._milliseconds, 23 * 60 * 60 * 1000 + 59 * 60 * 1000 + 10000, 'Add hour:minute');
 });
 
+test('add to moment', function (assert) {
+    var d = moment.duration({months: 1, seconds: -1});
+    var m = moment('2017-03-01').add(d);
+    assert.equal(m.month(), 2, 'Adds months before time');
+    assert.equal(m.date(), 31, 'Adds time after months');
+});
+
 test('add and bubble', function (assert) {
     var d;
 
-- 
2.47.2