From a4fe7d1cb05e7d8fbeec38fd5ccf1ce1ffff649a Mon Sep 17 00:00:00 2001
From: Jason Mitchell <jason.mitchell.w@gmail.com>
Date: Sun, 15 Jan 2017 19:40:12 -0800
Subject: [PATCH] assign should not mutate format object

---
 packages/ember-intl/addon/services/intl.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/ember-intl/addon/services/intl.js b/packages/ember-intl/addon/services/intl.js
index bbe6bfb82..96bcdb61a 100644
--- a/packages/ember-intl/addon/services/intl.js
+++ b/packages/ember-intl/addon/services/intl.js
@@ -31,7 +31,7 @@ function formatterProxy(formatType) {
     const formatter = this.owner.lookup(`ember-intl@formatter:format-${formatType}`);
 
     if (typeof options.format === 'string') {
-      options = assign(this.getFormat(formatType, options.format), options);
+      options = assign(assign({}, this.getFormat(formatType, options.format)), options);
     }