App-ccdiff

A colored diff that also colors inside changed lines

Synopsis

usage: ccdiff [options] file1 [file2]
       ccdiff --help | --man | --info
	file1 or file2 can be - (but not both)

Description

All command-line tools that show the difference between two files fall short in showing minor changes visually usefully. This tool tries to give the look and feel of diff --color or colordiff, but extending the display of colored output from red for deleted lines and green for added lines to red for deleted characters and green for added characters within the changed lines.

The tool has options to choose your own favorite color combinations, as long as they are supported by Term::ANSIColor.

If you want no colors but indicators below the removed/added characters in the output, which is very useful if you want to email the output, the option --no-color adds those indicators. With the --fancy option you will get Unicode characters.

Installation

Change the first line of ccdiff to start your favorite perl interpreter and then move the file to a folder in your $PATH, or install from CPAN:

$ cpan App::ccdiff

Alternatives

Command line / CLI

• diff

• diff --color

• colordiff

• klondiff

• diff-so-fancy

• git

  This however requires a long command:

$ git -c color.diff.new='bold reverse green' \
         -c color.diff.old='bold reverse red'   \
         diff --no-index -U0 --no-color \
              --word-diff=color --word-diff-regex=. \
             <file1> <file2>

An alternative for integration with git is diff-so-fancy

ASCII

• vimdiff

GUI

Please never use the xdiff command (if available at all), because it is included in many distributions and/or packages and they all work different or not at all. Some at not intended to be invoked from the command line.

The list is in increasing clarity of the tool being able to show minor changes in lines visually outstanding:

• mgdiff (C, X11)

• diffuse (Python)

• bcompare (C, X11, not freeware/opensource)

• kompare (C, X11, KDE)

• xxdiff (C, X11)

• meld (Python)

• kdiff3 (C, X11, Qt)

• tkdiff (Tcl/Tk)

Other (not checked yet)

Reasons for not checking include Windows and emacs.

• araxis
• bc
• bc3
• codecompare
• deltaworker
• diffmerge
• ecmerge
• emerge
• examdiff
• guiffy
• gvimdiff2
• gvimdiff3
• opendiff
• p4merge
• winmerge

Dependencies

This tool will run on recent perl distributions that have Algorithm::Diff installed. The modules Term::ANSIColor and Getopt::Long that are also used are part of the perl CORE distribution since at least version 5.6.0.

 suse#   zypper in perl-Algorithm-Diff

 centos# yum install -y perl-Algorithm-Diff

 other#  cpan Algorithm::Diff

Git integration

You can use ccdiff to show diffs in git. It may work like this:

$ git config --global diff.tool ccdiff
$ git config --global difftool.prompt false
$ git config --global difftool.ccdiff.cmd 'ccdiff --utf-8 -u -r $LOCAL $REMOTE'
$ git difftool SHA~..SHA
$ wget https://github.com/Tux/App-ccdiff/raw/master/Files/git-ccdiff \
    -O ~/bin/git-ccdiff
$ perl -pi -e 's{/pro/bin/perl}{/usr/bin/env perl}' ~/bin/git-ccdiff
$ chmod 755 ~/bin/git-ccdiff
$ git ccdiff SHA

Of course you can use curl instead of wget and you can choose your own (fixed) path to perl instead of using /usr/bin/env.

LIMITATIONS

There is no provision (yet) for coping with double-width characters.

Large datasets may consume all available memory, causing the diff to fail.

Not all that can be set from the configuration files can be overruled by command-line options.

LICENSE

The Artistic License 2.0

Copyright (c) 2018-2023 H.Merijn Brand