ice.fo.utils/Array/groupByKey.js

/* eslint-disable vue/max-len */
import _groupBy from 'lodash/groupBy';
import _get from 'lodash/get';
import _isEqual from 'lodash/isEqual';
import _isFunction from 'lodash/isFunction';

/**
 * Group a list of objects by [key] name. The [key] also supports properties path access e.g. 'user.profile.name'
 *
 * @example
 * groupByKey([{name: 'nikochin', age: 10}, {name: 'nikochin', age: 30}, {name: 'edward', age: 10}], 'name', true); // returns [ [{name: 'nikochin', age: 10}, {name: 'nikochin', age: 30}], [{name: 'edward', age: 10}] ]
 *
 * @param {any[]} list
 * @param {string|string[]} key
 * @param {boolean} keepOrder
 * @returns An list of objects list grouped by key
 */
export default function groupByKey(list, key, keepOrder = false) {
  if (!keepOrder) {
    return Object.values(_groupBy(list, (i) => _get(i, key)));
  }

  const result = [];
  const firstItem = _get(list, '0');
  const isFuncKey = _isFunction(key);

  let previousValue = isFuncKey ? key(firstItem) : _get(firstItem, key);
  let previousList = [];

  list.forEach((item) => {
    const value = isFuncKey ? key(item) : _get(item, key);

    if (_isEqual(value, previousValue)) {
      previousList.push(item);
    } else {
      result.push(previousList);
      previousList = [item];
      previousValue = value;
    }
  });

  if (previousList.length) {
    result.push(previousList);
  }

  return result;
}