rollup.config.ts

import resolve from 'rollup-plugin-node-resolve'
import commonjs from 'rollup-plugin-commonjs'
import camelCase from 'lodash.camelcase'
import typescript from 'rollup-plugin-typescript2'
import json from 'rollup-plugin-json'
import shebang from 'rollup-plugin-preserve-shebang'

const pkg = require('./package.json')

const libraryName = 'cga'

export default {
  input: `src/${libraryName}.ts`,
  acorn: {
    allowHashBang: true
  },
  output: [
    { file: pkg.main, name: camelCase(libraryName), format: 'umd', sourcemap: false },
    { file: pkg.module, format: 'es', sourcemap: false },
  ],
  // Indicate here external modules you don't wanna include in your bundle (i.e.: 'lodash')
  external: ["tslib"],
  watch: {
    include: 'src/**',
  },
  plugins: [
    // Allow json resolution
    json(),
    // Allow # for #!/usr/bin/env node
    shebang(),
    // Compile TypeScript files
    typescript({ useTsconfigDeclarationDir: true }),
    // Allow bundling cjs modules (unlike webpack, rollup doesn't understand cjs)
    commonjs({
      sourceMap: false
    }),
    // Allow node_modules resolution, so you can use 'external' to control
    // which external modules to include in the bundle
    // https://github.com/rollup/rollup-plugin-node-resolve#usage
    resolve(),

    // Resolve source maps to the original source
    // sourceMaps(),
  ],
}