From aee1af8c38b8384cf800e61c16e73f74cb155584 Mon Sep 17 00:00:00 2001
From: Joe Haddad <timer150@gmail.com>
Date: Wed, 10 Jan 2018 22:20:33 -0500
Subject: [PATCH] Specify ecma version (#3743)

---
 packages/react-scripts/config/webpack.config.prod.js | 1 +
 packages/react-scripts/package.json                  | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/react-scripts/config/webpack.config.prod.js b/packages/react-scripts/config/webpack.config.prod.js
index e1d4bc14a28..b99db8a27ef 100644
--- a/packages/react-scripts/config/webpack.config.prod.js
+++ b/packages/react-scripts/config/webpack.config.prod.js
@@ -293,6 +293,7 @@ module.exports = {
     // Minify the code.
     new UglifyJsPlugin({
       uglifyOptions: {
+        ecma: 5,
         compress: {
           warnings: false,
           // Disabled because of an issue with Uglify breaking seemingly valid code:
diff --git a/packages/react-scripts/package.json b/packages/react-scripts/package.json
index 33bff06c87c..d49640bd3fb 100644
--- a/packages/react-scripts/package.json
+++ b/packages/react-scripts/package.json
@@ -53,7 +53,7 @@
     "react-dev-utils": "^4.2.1",
     "style-loader": "0.19.0",
     "sw-precache-webpack-plugin": "0.11.4",
-    "uglifyjs-webpack-plugin": "1.1.4",
+    "uglifyjs-webpack-plugin": "1.1.6",
     "url-loader": "0.6.2",
     "webpack": "3.8.1",
     "webpack-dev-server": "2.9.4",