Diff XML documents

The goal of this module is to calculate diff between text content of two XML or HTML documents, preserving its tag structure:

import diff from '@emmetio/xml-diff';

const from = `<doc>
    <p>Lorem ipsum dolor sit amet <em>consectetur, adipisicing</em> elit.</p>
</doc>`;
const to = `<doc>
    <p>Lorem ipsum dolor sit amet aspernatur, <strong>doloribus</strong> in libero.</p>
</doc>`;

const result = diff(from, to);
console.log(result);
/*
<doc>
    <p>Lorem ipsum dolor sit amet <del>consectetur, adipisicing elit</del><ins>aspernatur, </ins><strong><ins>doloribus</ins></strong><ins> in libero</ins>.</p>
</doc>
*/

Project development is sponsored by Xcential Corporation

Features

• High performance: uses small and fast XML scanner, written in pure JavaScript.
• Supports multiple dialects: able to parse invalid HTML, even JSX and Angular templates.
• Works everywhere: doesn’t use browser DOM or APIs, runs in any browser, Node.JS and WebWorkers.

Installation & usage

Install it as regular npm module:

npm install @emmetio/xml-diff

This module exposes main diff(from, to) function which accepts two text documents and returns patched to document with updates marked with <ins> and <del> tags.

How it works

• Takes XML document and strips all markup data from it (tags, comments, CDATA etc.), leaving plain text content: <div>Hello <b>world</b>!</div> → Hello world!.
• Collapses and reduces insignificant white space characters like new lines, tabs and so on into a single space to reduce noise when comparing formatted documents.
• Performs diff with Google’s Diff Match Patch library.
• Applies patches to second document’s (to) plain content.
• Restores markup and whitespace data of original document