How to immutably rename object keys in JavaScript

In this Article we will go through how to immutably rename object keys only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const renameKeys = (keysMap, obj) => Object.keys(obj).reduce((acc, key) => ({ ...acc, ...{ [keysMap[key] || key]: obj[key] }}), {});

const obj = { a: 1, b: 2, c: 3 };
const keysMap = { a: 'd', b: 'e', c: 'f' };
renameKeys(keysMap, obj);       // { d: 1, e: 2, f: 3 }