Update build configuration (closes #36)

package.json

@@ -21,10 +21,9 @@
   ],
   "main": "dist/index.js",
   "module": "dist/index.mjs",
-  "es2015": "dist/index.es6.mjs",
   "types": "dist/index.d.ts",
   "scripts": {
-    "build": "rollup -c rollup.config.js",
+    "build": "rollup -c",
     "lint": "eslint --ext .ts src/",
     "prepare": "$npm_execpath run build",
     "test": "jest --coverage"
@@ -33,8 +32,6 @@
     "node": ">=6.4.0"
   },
   "devDependencies": {
-    "@babel/core": "^7.0",
-    "@babel/preset-env": "^7.0",
     "@types/jest": "^27.0",
     "@typescript-eslint/eslint-plugin": "^5.0",
     "@typescript-eslint/parser": "^5.0",
@@ -46,10 +43,9 @@
     "eslint-plugin-prettier": "^4.0",
     "jest": "^27.2",
     "prettier": "^2.4",
-    "rollup": "^1.23",
-    "rollup-plugin-babel": "^4.0",
-    "rollup-plugin-terser": "^5.0",
-    "rollup-plugin-typescript2": "^0.24",
+    "rollup": "^2.58",
+    "rollup-plugin-dts": "^4.0",
+    "rollup-plugin-typescript2": "^0.30",
     "ts-jest": "^27.0",
     "typescript": "^4.4"
   },

rollup.config.js

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 dokmic, Snowplow Analytics Ltd. All rights reserved.
+ * Copyright (c) 2019-2021 dokmic, Snowplow Analytics Ltd. All rights reserved.
  *
  * This program is licensed to you under the Apache License Version 2.0,
  * and you may not use this file except in compliance with the Apache License Version 2.0.
@@ -11,56 +11,46 @@
  * See the Apache License Version 2.0 for the specific language governing permissions and limitations there under.
  */
 
-import babel from 'rollup-plugin-babel';
-import { terser } from 'rollup-plugin-terser';
+import dts from 'rollup-plugin-dts';
 import typescript from 'rollup-plugin-typescript2';
-import terserOptions from './terser.json';
 
 export default [
   {
     input: 'src/index.ts',
     output: [
       {
+        dir: 'dist',
+        entryFileNames: '[name].js',
         exports: 'named',
-        file: 'dist/index.js',
         format: 'umd',
         name: 'SnowplowAnalyticsSdk',
         sourcemap: true,
         sourcemapExcludeSources: true,
       },
       {
-        file: 'dist/index.mjs',
+        dir: 'dist',
+        entryFileNames: '[name].mjs',
         format: 'esm',
       },
     ],
     plugins: [
       typescript({
-        cacheRoot: './node_modules/.cache/rpt2',
-        compilerOptions: {
-          declaration: false,
+        clean: true,
+        tsconfigOverride: {
+          compilerOptions: { removeComments: true },
         },
       }),
-      babel({ extensions: ['.ts'] }),
-      terser(terserOptions),
     ],
   },
-
   {
     input: 'src/index.ts',
     output: [
       {
-        file: 'dist/index.es6.mjs',
+        dir: 'dist',
+        entryFileNames: '[name].d.ts',
         format: 'esm',
       },
     ],
-    plugins: [
-      typescript({
-        cacheRoot: './node_modules/.cache/rpt2',
-        tsconfigOverride: {
-          useTsconfigDeclarationDir: true,
-        },
-      }),
-      terser(terserOptions),
-    ],
+    plugins: [dts()],
   },
 ];

tsconfig.json

@@ -1,7 +1,5 @@
 {
   "compilerOptions": {
-    "declaration": true,
-    "declarationDir": "./dist",
     "esModuleInterop": true,
     "lib": [
       "es6"