using diff-match-patch-es this library compares two texts, computes the changes between them, and renders them nicely for different environents:

npm install same-diff

JS API

import {diffCli, diffHtml, diffConsole } from 'same-diff'

let input='the best of times'
let output='the blurst of times'

// show a nice command-line diff
diffCli(input, output)

// render a nice HTML diff
let html = diffHtml(input, output)
document.body.innerHTML = html

// show a nice diff browser dev console
diffConsole(input, output)

Output

diffHtml - basic stylable html

diffCli - command line output

diffConsole - browser dev console

CLI API

npm install -g same-diff

same-diff <input> <output> 

same-diff ./input.txt ./output.txt --fmt=html

MIT