From 1e9247a96111b55e72a3ef8ac32cc1cf0baadefe Mon Sep 17 00:00:00 2001
From: Charlie Briggs <charliebriggs@gmail.com>
Date: Thu, 9 Nov 2017 10:23:48 +0000
Subject: [PATCH] Replace babel presets with preset-env (#499)

This is after running tests to determine that the output is identical for
es2015,2016,2016 and es3 code (output string is deepEquals).

es3 presets are _not_ included in preset-env, but without configuration it is identical
to the es-preset-20xx modules.

It would be nice to have some form of snapshot testing to verify this.
---
 config/webpack.config.js |  6 ++----
 package-lock.json        | 33 +++++++++++----------------------
 package.json             |  4 +---
 3 files changed, 14 insertions(+), 29 deletions(-)

diff --git a/config/webpack.config.js b/config/webpack.config.js
index fb3a0003..880215f4 100644
--- a/config/webpack.config.js
+++ b/config/webpack.config.js
@@ -56,13 +56,11 @@ module.exports = {
 						options: {
 							compact: false,
 
-							// TODO: Look into using preset-env instead and specifying our minimum versions
+							// TODO: Look into specifying our minimum versions in preset-env
 							// for enhanced experience instead of making everything become ES5
 							presets: [
 								require.resolve('babel-preset-es3'),
-								require.resolve('babel-preset-es2015'),
-								require.resolve('babel-preset-es2016'),
-								require.resolve('babel-preset-es2017')
+								require.resolve('babel-preset-env')
 							],
 							plugins: [
 								[
diff --git a/package-lock.json b/package-lock.json
index 07eccc21..be5b5741 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -877,12 +877,14 @@
         "babel-types": "6.26.0"
       }
     },
-    "babel-preset-es2015": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-preset-es2015/-/babel-preset-es2015-6.24.1.tgz",
-      "integrity": "sha1-1EBQ1rwsn+6nAqrzjXJ6AhBTiTk=",
+    "babel-preset-env": {
+      "version": "1.6.1",
+      "resolved": "https://registry.npmjs.org/babel-preset-env/-/babel-preset-env-1.6.1.tgz",
+      "integrity": "sha512-W6VIyA6Ch9ePMI7VptNn2wBM6dbG0eSz25HEiL40nQXCsXGTGZSTZu1Iap+cj3Q0S5a7T9+529l/5Bkvd+afNA==",
       "requires": {
         "babel-plugin-check-es2015-constants": "6.22.0",
+        "babel-plugin-syntax-trailing-function-commas": "6.22.0",
+        "babel-plugin-transform-async-to-generator": "6.24.1",
         "babel-plugin-transform-es2015-arrow-functions": "6.22.0",
         "babel-plugin-transform-es2015-block-scoped-functions": "6.22.0",
         "babel-plugin-transform-es2015-block-scoping": "6.26.0",
@@ -905,24 +907,11 @@
         "babel-plugin-transform-es2015-template-literals": "6.22.0",
         "babel-plugin-transform-es2015-typeof-symbol": "6.23.0",
         "babel-plugin-transform-es2015-unicode-regex": "6.24.1",
-        "babel-plugin-transform-regenerator": "6.26.0"
-      }
-    },
-    "babel-preset-es2016": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-preset-es2016/-/babel-preset-es2016-6.24.1.tgz",
-      "integrity": "sha1-+QC/k+LrwNJ235uKtZck6/2Vn4s=",
-      "requires": {
-        "babel-plugin-transform-exponentiation-operator": "6.24.1"
-      }
-    },
-    "babel-preset-es2017": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-preset-es2017/-/babel-preset-es2017-6.24.1.tgz",
-      "integrity": "sha1-WXvq37n38gi8/YoS6bKym4svFNE=",
-      "requires": {
-        "babel-plugin-syntax-trailing-function-commas": "6.22.0",
-        "babel-plugin-transform-async-to-generator": "6.24.1"
+        "babel-plugin-transform-exponentiation-operator": "6.24.1",
+        "babel-plugin-transform-regenerator": "6.26.0",
+        "browserslist": "2.5.1",
+        "invariant": "2.2.2",
+        "semver": "5.4.1"
       }
     },
     "babel-preset-es3": {
diff --git a/package.json b/package.json
index 7f0ce4ba..900cd47c 100644
--- a/package.json
+++ b/package.json
@@ -18,9 +18,7 @@
     "babel-loader": "^7.1.2",
     "babel-plugin-add-module-exports": "^0.2.1",
     "babel-plugin-transform-runtime": "^6.23.0",
-    "babel-preset-es2015": "^6.24.1",
-    "babel-preset-es2016": "^6.24.1",
-    "babel-preset-es2017": "^6.24.1",
+    "babel-preset-env": "^1.6.1",
     "babel-preset-es3": "^1.0.1",
     "bower": "^1.8.2",
     "bower-resolve-webpack-plugin": "^1.0.4",