mirror-key-value/index.js

Mirroring to keys and values from array of strings

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = mirrorKeyValue;
/*!
 * @license mirror-key-value
 * (c) sugarshin
 * License: MIT
 */

/**
 * mirrorKeyValue
 *
 * @param {String[]} array
 * @param {Object} [base = {}]
 * @returns {Object}
 */
function mirrorKeyValue(array) {
  var base = arguments.length <= 1 || arguments[1] === undefined ? {} : arguments[1];

  if (!Array.isArray(array) || !isStrings(array)) {
    throw new TypeError('should be an array of string.');
  }
  return array.reduce(function (result, str) {
    if (result[str]) {
      return result;
    }
    result[str] = str;
    return result;
  }, base);
}

function isStrings(array) {
  return array.every(function (val) {
    return typeof val === 'string';
  });
}