Beautifier and language aware code comparison tool for many languages. It also minifies and a few other things.
JavaScript HTML CSS
Latest commit 7e4ceb3 Dec 4, 2016 @prettydiff committed on GitHub Merge pull request #395 from prettydiff/2.1.15
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JSLint @ 7e3d140 fixing submodule management Sep 7, 2016
ace Adding Liquid Templates and improved template stability Mar 8, 2016
api fixes #381 Dec 2, 2016
bin Adding support for wrapping markup tags and attributes and exposing t… Apr 3, 2015
css minor adjustments to tool css Nov 19, 2016
guide fixes #353 Sep 2, 2016
images updated logosand readme. no code updated Mar 18, 2013
lib adding test samples for #394 Dec 4, 2016
test adding test samples for #394 Dec 4, 2016
.biddlerc creating additional publication variants Nov 11, 2016
.bithoundrc Update to TWIG support and some updates to the diff reports Feb 23, 2016
.bower.json Fixes #383 Nov 19, 2016
.codeclimate.yml adding codeclimate config Apr 19, 2016
.gitmodules Updating test runner to run on Windows Apr 18, 2016
.prettydiffrc bug fixes Aug 16, 2016
.travis.yml adding support for Travis OSX builds Jul 5, 2016 2.1.9 Sep 7, 2016
appveyor.yml preparing for biddle publication in production Nov 5, 2016
bower.json Fixes #383 Nov 19, 2016 updating changelog Dec 4, 2016
documentation.xhtml fixes #381 Dec 2, 2016
inch.json solving issue #290 and a variety of bugs Apr 21, 2016
index.xhtml fixes #381 Dec 2, 2016
license.txt bug fixes in node-local.js file Nov 2, 2015
overview.xhtml creating a guide describing how to write parsers Aug 5, 2016
package.json Fixes #383 Nov 19, 2016
prettydiff.js updating changelog Dec 4, 2016
proxy.php extended cross-domain AJAX support Aug 9, 2011
samples.xhtml creating a guide describing how to write parsers Aug 5, 2016

Try it online at

Pretty Diff logo Pretty Diff

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Language aware code comparison tool for several web based languages. It also beautifies, minifies, and a few other things.

Benefits - see overview page for more details

Executing Pretty Diff

Run with Node.js / CommonJS / RequireJS

A Node.js command line utility is provided by api/node-local.js. This file can execute in the following modes:

  • auto - Determine if the resource is text, a file, or a directory and process as such (except that directories are processed with the subdirectory option)
  • screen - code input is on the command line and output is to the command line
  • filescreen - code input is in a file and the output is to the command line
  • file - the input and the output reside in files
  • directory - everything in a directory is processed into a specified output directory except ".", "..", and subdirectories
  • subdirectory - process the entire directory tree

Execute in the context of a NodeJS application

Add this code to your application

var prettydiff = require("prettydiff"),
    args       = {
        source: "asdf",
        diff  : "asdd",
        lang  : "text"
    output     = prettydiff(args);

Execute from the command line

Run in windows

node api/node-local.js source:"c:\myDirectory" readmethod:"subdirectory" diff:"c:\myOtherDirectory"

Run in Linux and OSX

node api/node-local.js source:"myDirectory" mode:"beautify" readmethod:"subdirectory" output:"path/to/outputDirectory"

To see a man page provide no arguments or these: help, man, manual

node api/node-local.js h
node api/node-local.js help
node api/node-local.js man
node api/node-local.js manual

To see only the version number supply only v or version as an argument:

node api/node-local.js v
node api/node-local.js version

To see a list of current settings on the console supply list as an argument:

node api/node-local.js l
node api/node-local.js list

Set configurations with a .prettydiffrc file.

Pretty Diff will first look for a .prettydiffrc file from the current directory in the command prompt. If the .prettydiffrc is not present in the current directory it will then look for it in the application's directory.

The .prettydiffrc first checks for JSON format. This allows a simple means of defining options in a file. It also allows a JavaScript application format so that options can be set conditionally.

Run in a web browser with api/dom.js

Please feel free to use index.xhtml file to supplement dom.js. Otherwise, dom.js requires supplemental assistance to map DOM nodes from an HTML source. dom.js is fault tolerant so nodes mapped to the supplied index.xhtml don't need to be supported from custom HTML.

To run Pretty Diff using dom.js include the following two script tags and bind the global.prettydiff.pd.recycle() function to the executing event. Please refer to index.xhtml for an HTML example and documentation.xhtml for option and execution information.

<script src="lib/global.js" type="application/javascript"></script>
<script src="lib/language.js" type="application/javascript"></script>
<script src="lib/options.js" type="application/javascript"></script>
<script src="lib/finalFile.js" type="application/javascript"></script>
<script src="lib/safeSort.js" type="application/javascript"></script>
<script src="ace/ace.js" type="application/javascript"></script> **(optional)**
<script src="api/dom.js" type="application/javascript"></script>
<script src="lib/csspretty.js" type="application/javascript"></script>
<script src="lib/csvpretty.js" type="application/javascript"></script>
<script src="lib/diffview.js" type="application/javascript"></script>
<script src="lib/jspretty.js" type="application/javascript"></script>
<script src="lib/markuppretty.js" type="application/javascript"></script>
<script src="prettydiff.js" type="application/javascript"></script>

Execute with vanilla JS

var global = {},
    args   = {
        source: "asdf",
        diff  : "asdd",
        lang  : "text"
    output = prettydiff(args);

Run Pretty Diff in Atom code editor with the atom-beautify package.

Run the unit tests

cd prettydiff
node test/lint.js



@documentation English:

@licstart The following is the entire license notice for Pretty Diff.

This code may not be used or redistributed unless the following conditions are met:

  • Prettydiff created by Austin Cheney originally on 3 Mar 2009.
  • The use of diffview.js and prettydiff.js must contain the following copyright:
  • Copyright (c) 2007, Snowtide Informatics Systems, Inc. All rights reserved.
    • Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
    • Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
    • Neither the name of the Snowtide Informatics Systems nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
    • used as diffview function
  • The code mentioned above has significantly expanded documentation in each of the respective function's external JS file as linked from the documentation page:
  • In addition to the previously stated requirements any use of any component, aside from directly using the full files in their entirety, must restate the license mentioned at the top of each concerned file.

    If each and all these conditions are met use, extension, alteration, and redistribution of Pretty Diff and its required assets is unlimited and free without author permission.

    @licend The above is the entire license notice for Pretty Diff.