Добавил поддержку babel

cp/javascript/src/typos.js

+

cp/package-lock.json

@@ -459,6 +459,17 @@
         "babel-template": "6.26.0"
       }
     },
+    "babel-loader": {
+      "version": "7.1.4",
+      "resolved": "https://registry.npmjs.org/babel-loader/-/babel-loader-7.1.4.tgz",
+      "integrity": "sha512-/hbyEvPzBJuGpk9o80R0ZyTej6heEOr59GoEUtn8qFKbnx4cJm9FWES6J/iv644sYgrtVw9JJQkjaLW/bqb5gw==",
+      "dev": true,
+      "requires": {
+        "find-cache-dir": "1.0.0",
+        "loader-utils": "1.1.0",
+        "mkdirp": "0.5.1"
+      }
+    },
     "babel-messages": {
       "version": "6.23.0",
       "resolved": "https://registry.npmjs.org/babel-messages/-/babel-messages-6.23.0.tgz",

cp/package.json

@@ -6,6 +6,9 @@
   "private": true,
   "dependencies": {},
   "devDependencies": {
+    "babel-core": "^6.26.0",
+    "babel-loader": "^7.1.4",
+    "babel-preset-es2015": "^6.24.1",
     "webpack": "^4.4.1",
     "webpack-cli": "^2.0.13"
   },

cp/webpack.config.js

 const path = require("path");
 
 module.exports = {
-    entry: "./javascript/typos.js",
+    entry: [
+        // Application code
+        "./javascript/src/typos.js",
+    ],
+
     output: {
         filename: "typos-page.js",
         path: path.resolve(__dirname, "javascript/dist")
     },
-    mode: "development"
+
+    mode: "development",
 };
 
+module.loaders = [
+    {
+        loader: "babel-loader",
+
+        include: [
+            path.resolve(__dirname, "javascript/src")
+        ],
+
+        test: "/\.js$/",
+
+        query: {
+            presets: ['es2015']
+        }
+    }
+];
+