twbs--bootstrap/build/rollup.config.js

'use strict'

const path = require('path')
const { babel } = require('@rollup/plugin-babel')
const { nodeResolve } = require('@rollup/plugin-node-resolve')
const banner = require('./banner.js')

const BUNDLE = process.env.BUNDLE === 'true'
const ESM = process.env.ESM === 'true'

let fileDest = `bootstrap${ESM ? '.esm' : ''}`
const external = ['popper.js']
const plugins = [
  babel({
  // Only transpile our source code
    exclude: 'node_modules/**',
    // Include the helpers in the bundle, at most one copy of each
    babelHelpers: 'bundled'
  })
]
const globals = {
  'popper.js': 'Popper'
}

if (BUNDLE) {
  fileDest += '.bundle'
  // Remove last entry in external array to bundle Popper
  external.pop()
  delete globals['popper.js']
  plugins.push(nodeResolve())
}

const rollupConfig = {
  input: path.resolve(__dirname, `../js/index.${ESM ? 'esm' : 'umd'}.js`),
  output: {
    banner,
    file: path.resolve(__dirname, `../dist/js/${fileDest}.js`),
    format: ESM ? 'esm' : 'umd',
    globals
  },
  external,
  plugins
}

if (!ESM) {
  rollupConfig.output.name = 'bootstrap'
}

module.exports = rollupConfig