From e9134d731dd723616831e41ec0bfda14486e3562 Mon Sep 17 00:00:00 2001
From: Aymeric Bouzy <aymeric.bouzy@gmail.com>
Date: Wed, 23 Nov 2016 15:33:17 +0100
Subject: [PATCH] create setTime function

---
 src/lib/moment/start-end-of.js | 5 +++--
 src/lib/units/hour.js          | 8 ++++++++
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/lib/moment/start-end-of.js b/src/lib/moment/start-end-of.js
index 02f982479a..dedfdb7451 100644
--- a/src/lib/moment/start-end-of.js
+++ b/src/lib/moment/start-end-of.js
@@ -1,4 +1,5 @@
 import { normalizeUnits } from '../units/aliases';
+import { setTime } from '../units/hour';
 
 export function startOf (units) {
     units = normalizeUnits(units);
@@ -16,8 +17,8 @@ export function startOf (units) {
         case 'isoWeek':
         case 'day':
         case 'date':
-            this.hours(0);
-            /* falls through */
+            setTime(this, 0, 0, 0, 0);
+            break;
         case 'hour':
             this.minutes(0);
             /* falls through */
diff --git a/src/lib/units/hour.js b/src/lib/units/hour.js
index d5733fbbcf..8a7d984910 100644
--- a/src/lib/units/hour.js
+++ b/src/lib/units/hour.js
@@ -8,6 +8,7 @@ import { HOUR, MINUTE, SECOND } from './constants';
 import toInt from '../utils/to-int';
 import zeroFill from '../utils/zero-fill';
 import getParsingFlags from '../create/parsing-flags';
+import { hooks } from '../utils/hooks';
 
 // FORMATTING
 
@@ -136,3 +137,10 @@ export function localeMeridiem (hours, minutes, isLower) {
 // a new timezone) makes sense. Adding/subtracting hours does not follow
 // this rule.
 export var getSetHour = makeGetSet('Hours', true);
+
+export function setTime (mom, hours, minutes, seconds, milliseconds) {
+    if (mom.isValid()) {
+        mom._d['set' + (mom._isUTC ? 'UTC' : '') + 'Hours'](hours, minutes, seconds, milliseconds);
+        hooks.updateOffset(mom, true);
+    }
+}