File Arguments

Diffing Files


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

Diffing Directories


# 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.

$ 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.


# For example:
$ difft sample_files/conflicts.el

Language Detection

Difftastic guesses the language used based on the file extension, file name, and the contents of the first lines. To see the languages available, and the associated file names, use the --list-languages option.

$ difft --list-languages

You can override language detection for specific file globs using the --override option.


# For example, treating .h files as C rather than C++:
$ difft --override=*.h:c sample_files/preprocesor_1.h sample_files/preprocesor_2.h


Difftastic includes a range of configuration CLI options, see difft --help for the full list.

Difftastic can also be configured with environment variables. These are also visible in --help.

For example, DFT_BACKGROUND=light is equivalent to --background=light. This is useful when using VCS tools like git, where you are not invoking the difft binary directly.

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.