lodash/internal/createObjectMapper.js

import baseCallback from './baseCallback';
import baseForOwn from './baseForOwn';

/**
 * Creates a function for `_.mapKeys` or `_.mapValues`.
 *
 * @private
 * @param {boolean} [isMapKeys] Specify mapping keys instead of values.
 * @returns {Function} Returns the new map function.
 */
function createObjectMapper(isMapKeys) {
  return function(object, iteratee, thisArg) {
    var result = {};
    iteratee = baseCallback(iteratee, thisArg, 3);

    baseForOwn(object, function(value, key, object) {
      var mapped = iteratee(value, key, object);
      key = isMapKeys ? mapped : key;
      value = isMapKeys ? value : mapped;
      result[key] = value;
    });
    return result;
  };
}

export default createObjectMapper;