lodash-keyBy-mapKeys.js

const { keyBy, mapKeys } = require("lodash");

let result;

const current = {
  firstName: "Ahmed",
  lastName: "Mehri",
  age: 30
};

const expected = {
  Ahmed: {
    firstName: "Ahmed",
    lastName: "Mehri",
    age: 30
  }
};

// doesn't work either (wrong usage of mapKeys)
result = mapKeys(current, "firstName"); // { undefined: 30 }

// doesn't work either (correct usage of mapKeys)
result = mapKeys(current, (value, key) => value); // { 30: 30, Ahmed: 'Ahmed', Mehri: 'Mehri' }

// does not work
result = keyBy(current, "firstName"); // { undefined: 30 }

// works only on collection
const collection = [current];
result = keyBy(collection, "firstName"); // { Ahmed: { firstName: 'Ahmed', lastName: 'Mehri', age: 30 } }