rollup.config.js

// this is the top-level rollup config
//
// each child rollup config *must* use full paths, e.g.
// const DESTINATION_FILE = path.join(__dirname, '..', 'lib/index.js');
// const INPUT_FILE = path.join(__dirname, '..', 'src/index.js');

const requireGlob = require('require-glob');
const path = require('path');
const _ = require('lodash');

const allRollupConfigs = requireGlob.sync(['../packages/**/rollup.config.js'], {
  reducer: (options, tree, fileObj) => {
    const packageName = options.keygen(fileObj)[0];
    if (!packageName) {
      console.log(fileObj);
      throw new Error('error with rollup config');
    }

    const { exports: config } = fileObj;
    return Array.from(tree).concat(config);
  },
});

module.exports = allRollupConfigs;