add babel to build

Author: kmck

package.json

@@ -23,7 +23,8 @@
     "eslint-plugin-import": "^2.12.0",
     "glob": "^7.1.2",
     "jest-cli": "^23.1.0",
-    "rollup": "^0.59.4"
+    "rollup": "^0.59.4",
+    "rollup-plugin-babel": "^3.0.4"
   },
   "dependencies": {
     "hastscript": "^3.1.0"

rollup.config.js

@@ -1,3 +1,4 @@
+import babel from 'rollup-plugin-babel';
 import pkg from './package.json';
 
 export default {
@@ -6,5 +7,13 @@ export default {
     { file: pkg.main, format: 'cjs' },
     { file: pkg.module, format: 'es' },
   ],
+  plugins: [
+    babel({
+      presets: [
+        ['env', { targets: { browsers: '>0.25%' }, modules: false }],
+      ],
+      babelrc: false,
+    }),
+  ],
   external: ['hastscript'],
 };

yarn.lock

@@ -1416,6 +1416,10 @@ estraverse@^4.0.0, estraverse@^4.1.0, estraverse@^4.1.1, estraverse@^4.2.0:
   version "4.2.0"
   resolved "https://registry.yarnpkg.com/estraverse/-/estraverse-4.2.0.tgz#0dee3fed31fcd469618ce7342099fc1afa0bdb13"
 
+estree-walker@^0.2.1:
+  version "0.2.1"
+  resolved "https://registry.yarnpkg.com/estree-walker/-/estree-walker-0.2.1.tgz#bdafe8095383d8414d5dc2ecf4c9173b6db9412e"
+
 esutils@^2.0.2:
   version "2.0.2"
   resolved "https://registry.yarnpkg.com/esutils/-/esutils-2.0.2.tgz#0abf4f1caa5bcb1f7a9d8acc6dea4faaa04bac9b"
@@ -3450,6 +3454,19 @@ rimraf@^2.2.8, rimraf@^2.5.4, rimraf@^2.6.1:
   dependencies:
     glob "^7.0.5"
 
+rollup-plugin-babel@^3.0.4:
+  version "3.0.4"
+  resolved "https://registry.yarnpkg.com/rollup-plugin-babel/-/rollup-plugin-babel-3.0.4.tgz#41b3e762fe64450dd61da3105a2cf7ad76be4edc"
+  dependencies:
+    rollup-pluginutils "^1.5.0"
+
+rollup-pluginutils@^1.5.0:
+  version "1.5.2"
+  resolved "https://registry.yarnpkg.com/rollup-pluginutils/-/rollup-pluginutils-1.5.2.tgz#1e156e778f94b7255bfa1b3d0178be8f5c552408"
+  dependencies:
+    estree-walker "^0.2.1"
+    minimatch "^3.0.2"
+
 rollup@^0.59.4:
   version "0.59.4"
   resolved "https://registry.yarnpkg.com/rollup/-/rollup-0.59.4.tgz#6f80f7017c22667ff1bf3e62adf8624a44cc44aa"