unflatn/lib/index.js

The opposite of `flatten`

'use strict'

const _set = require('lodash/set')
const _setWith = require('lodash/setWith')
/**
 * @id unflatten
 * @function unflatten
 * Opposite of `flatten-obj`. Unflattens an object with delimited keys
 * @param  {object} subject - Object that needs to be unflattened
 * @param  {object|string|boolean} [opts] - Optional.
 * - Provide a string as a shortcut for `{ separator: opts }`
 * - Provide a boolean as a shorcut for `{ objectMode: opts }`
 * - Provide an object to set both options `{ separator: '/', objectMode: true }`
 * - Available options:
 *   + **separator** (*string*) - defaults to `'.'`
 *   + **objectMode** (*boolean*) - defaults to `false`
 * @return {object} obj - Nested Javascript object
 */

module.exports = unflatten

function unflatten (obj, opts) {
  var separator = '.'
  var objectMode = false
  if (typeof opts === 'string') {
    separator = opts
  } else if (typeof opts === 'boolean') {
    objectMode = opts
  } else if (opts) {
    separator = opts.separator || separator
    objectMode = opts.objectMode
  }
  const dotSep = (separator === '.')
  var re = new RegExp(separator, 'g')
  var newObj = {}
  for (let path in obj) {
    if (objectMode) {
      _setWith(newObj, dotSep ? path : path.replace(re, '.'), obj[path], Object)
    } else {
      _set(newObj, dotSep ? path : path.replace(re, '.'), obj[path])
    }
  }
  return newObj
}