rollup.config.js

import buble from '@rollup/plugin-buble'
import replace from '@rollup/plugin-replace'
import resolve from '@rollup/plugin-node-resolve'
import commonjs from '@rollup/plugin-commonjs'
import { terser } from 'rollup-plugin-terser'
import pkg from './package.json'

const banner = `/*!
 * vuex v${pkg.version}
 * (c) ${new Date().getFullYear()} Evan You
 * @license MIT
 */`

const configs = [
  {
    input: 'src/index.js',
    file: 'dist/vuex.esm-browser.js',
    format: 'es',
    browser: true,
    env: 'development'
  },
  {
    input: 'src/index.js',
    file: 'dist/vuex.esm-browser.prod.js',
    format: 'es',
    browser: true,
    env: 'production'
  },
  {
    input: 'src/index.js',
    file: 'dist/vuex.esm-bundler.js',
    format: 'es',
    env: 'development'
  },
  {
    input: 'src/index.cjs.js',
    file: 'dist/vuex.global.js',
    format: 'iife',
    env: 'development'
  },
  {
    input: 'src/index.cjs.js',
    file: 'dist/vuex.global.prod.js',
    format: 'iife',
    minify: true,
    env: 'production'
  },
  {
    input: 'src/index.cjs.js',
    file: 'dist/vuex.cjs.js',
    format: 'cjs',
    env: 'development'
  }
]

function createEntries() {
  return configs.map((c) => createEntry(c))
}

function createEntry(config) {
  const isGlobalBuild = config.format === 'iife'
  const isBundlerBuild = config.format !== 'iife' && !config.browser
  const isBundlerESMBuild = config.format === 'es' && !config.browser

  const c = {
    external: ['vue'],
    input: config.input,
    plugins: [],
    output: {
      banner,
      file: config.file,
      format: config.format,
      exports: 'auto',
      globals: {
        vue: 'Vue'
      }
    },
    onwarn: (msg, warn) => {
      if (!/Circular/.test(msg)) {
        warn(msg)
      }
    }
  }

  if (isGlobalBuild) {
    c.output.name = c.output.name || 'Vuex'
  }

  if (!isGlobalBuild) {
    c.external.push('@vue/devtools-api')
  }

  c.plugins.push(
    replace({
      preventAssignment: true,
      __VERSION__: pkg.version,
      __DEV__: isBundlerBuild
        ? `(process.env.NODE_ENV !== 'production')`
        : config.env !== 'production',
      __VUE_PROD_DEVTOOLS__: isBundlerESMBuild
        ? '__VUE_PROD_DEVTOOLS__'
        : 'false'
    })
  )

  if (config.transpile !== false) {
    c.plugins.push(
      buble({
        transforms: { asyncAwait: false, forOf: false }
      })
    )
  }

  c.plugins.push(resolve())
  c.plugins.push(commonjs())

  if (config.minify) {
    c.plugins.push(terser({ module: config.format === 'es' }))
  }

  return c
}

export default createEntries()