Usage

This page describes how to use the difft binary directly. See also the Git, Mercurial, Fossil, or Jujutsu pages for instructions on how to configure them to use difftastic.

File Arguments

Diffing Files

bash

$ difft FIRST-FILE SECOND-FILE

# For example:
$ difft sample_files/simple_1.js sample_files/simple_2.js

Diffing Directories

bash

$ difft FIRST-DIRECTORY SECOND-DIRECTORY

# For example:
$ difft sample_files/dir_1/ sample_files/dir_2/

Difftastic will recursively walk the two directories, diffing files with the same name.

The --skip-unchanged option is useful when diffing directories that contain many unchanged files.

Reading stdin

You can read a file from stdin by specifying - as the file path.

bash

$ difft - SECOND-FILE

# For example:
$ cat sample_files/simple_1.js | difft - sample_files/simple_2.js

Files With Conflicts

(Added in version 0.50.)

If you have a file with <<<<<<< conflict markers, you can pass it as a single argument to difftastic. Difftastic will construct the two file states and diff those.

bash

$ difft FILE-WITH-CONFLICTS

# For example:
$ difft sample_files/conflicts.el

Configuration Options

Every difftastic option can be set with a command line argument or an environment variable. For example, DFT_BACKGROUND=light is equivalent to --background=light.

Environment variables are often useful when using VCS tools like git, because they invoke the difft binary directly.

For a full list of configuration options, see --help.

$ difft --help
...
OPTIONS:
        --background <BACKGROUND>
            Set the background brightness. Difftastic will prefer brighter colours on dark backgrounds.

            [env: DFT_BACKGROUND=]
            [default: dark]
            [possible values: dark, light]
...

Exit Codes

2: Difftastic was given invalid arguments. This includes invalid usage (e.g. the wrong number of arguments) as well as paths that difftastic cannot read (e.g. non-existent paths or insufficient permissions).

1: When called with --exit-code, difftastic will return an exit code of 1 when it finds any syntactic changes (in text files) or byte changes (in binary files).

0: All other cases.