Parses location.search string in ES2015

parse-location-search.js

/*
 * A method by @tmetler done in ES2015
 * Original method source http://www.timetler.com/2013/11/14/location-search-split-one-liner/
 */

/**
 * Parses location.search string
 * @return {Obeject} Search parameters
 */
function parseSearch() {
  // Remove the '?' at the start of the string and split out each assignment
  return location.search.slice(1).split('&') 
    // Split each array item into [key, value]
    // ignore empty string if search is empty
    .map(item => { if (item) return item.split('='); })
    // Remove undefined in the case the search is empty
    .filter(x => !!x)
    // Return the value of the chain operation
    .reduce((result, [key, val]) => {
      // Check whenever query contains array values
      if (key.match(/\[\]$/)) {
        const realKey = key.substr(0, key.length - 2);
        let array = result[realKey] || [];
        array.push(decodeURIComponent(val));
        return Object.assign(result, { [realKey] : array });
      } else {
        return Object.assign(result, { [key]: decodeURIComponent(val) });
      }
    }, {});
}