build(rollup): add es module to package

Author: csvenke

package-lock.json

@@ -7,10 +7,12 @@
     "type": "git",
     "url": "https://github.com/csvenke/react-semantics.git"
   },
-  "main": "index.min.js",
+  "main": "index.js",
+  "module": "index.es.js",
   "types": "types/index.d.ts",
   "files": [
-    "index.min.js",
+    "index.js",
+    "index.es.js",
     "types/index.d.ts",
     "types/components"
   ],
@@ -54,6 +56,7 @@
     "react-styleguidist": "^7.1.0",
     "react": "^16.4.1",
     "rimraf": "^2.6.2",
+    "rollup-plugin-terser": "^1.0.1",
     "rollup-plugin-typescript2": "^0.16.1",
     "rollup-plugin-uglify": "^4.0.0",
     "rollup": "^0.63.4",

package.json

@@ -1,13 +1,14 @@
 import typescript from 'rollup-plugin-typescript2';
 import { uglify } from 'rollup-plugin-uglify';
+import { terser } from 'rollup-plugin-terser';
 import pkg from './package.json';
 
 const externals = [
   ...(Object.keys(pkg.dependencies) || {}),
   ...(Object.keys(pkg.peerDependencies) || {}),
 ];
 
-const createConfig = ({ output } = {}) => ({
+const createConfig = ({ output, plugins } = {}) => ({
   input: 'src/index.ts',
   output,
   external: externals,
@@ -17,16 +18,17 @@ const createConfig = ({ output } = {}) => ({
       tsconfig: './tsconfig.build.json',
       typescript: require('typescript'),
     }),
-    uglify(),
+    ...plugins,
   ],
 });
 
 export default [
   createConfig({
-    output: {
-      file: 'lib/index.min.js',
-      format: 'cjs',
-      exports: 'named',
-    },
+    output: { file: 'lib/index.js', format: 'cjs' },
+    plugins: [uglify()],
+  }),
+  createConfig({
+    output: { file: 'lib/index.es.js', format: 'es' },
+    plugins: [terser()],
   }),
 ];