rollup.config.js

const fs = require('fs')
const path = require('path')
const cleaner = require('rollup-plugin-cleaner')
const external = require('rollup-plugin-peer-deps-external')
const postcss = require('rollup-plugin-postcss')
const commonjs = require('@rollup/plugin-commonjs')
const {babel} = require('@rollup/plugin-babel')
const {nodeResolve: resolve} = require('@rollup/plugin-node-resolve')
const {ifProd} = require('./utils/env')

const srcPath = (...p) => path.resolve.apply(undefined, [__dirname, 'src', ...p].filter(Boolean))
const libPath = (...p) => path.resolve.apply(undefined, [__dirname, 'lib', ...p].filter(Boolean))

module.exports = (name) => {
  const indexFile = fs.readdirSync(srcPath(name)).find((f) => f.startsWith('index.'))
  return {
    input: srcPath(name, indexFile),
    output: [
      {
        dir: libPath(name),
        format: 'cjs',
        sourcemap: true,
      },
    ],
    plugins: [
      external(),
      postcss({
        modules: {
          camelCase: true,
          generateScopedName: '[hash:base64]',
        },
        autoModules: false,
        minimize: false,
        extensions: ['.css', '.scss'],
      }),
      resolve({
        extensions: ['.js', '.jsx', '.ts', '.tsx'],
      }),
      babel({
        exclude: '**/node_modules/**',
        extensions: ['.js', '.jsx', '.ts', '.tsx'],
        babelHelpers: 'runtime',
      }),
      commonjs({
        include: 'node_modules/**',
      }),
      ifProd(
        cleaner({
          targets: [libPath(name)],
        })
      ),
    ].filter(Boolean),
    external: (id) =>
      !!(
        id.match(/@babel\/runtime/) ||
        id.startsWith('config:') ||
        id.startsWith('part:') ||
        id.startsWith('@sanity/')
      ),
  }
}