what is mv function in js code example

Example 1: node filesystem change directory of a file

const {promisify} = require('util');
const fs = require('fs');
const {join} = require('path');
const mv = promisify(fs.rename);

const moveThem = async () => {
  // Move file ./bar/foo.js to ./baz/qux.js
  const original = join(__dirname, 'bar/foo.js');
  const target = join(__dirname, 'baz/qux.js'); 
  await mv(original, target);
}

moveThem();

Example 2: node filesystem change directory of a file

var fs = require('fs-extra')

fs.move('/tmp/somefile', '/tmp/does/not/exist/yet/somefile', function (err) {
 if (err) return console.error(err)
 console.log("success!")
})