difftastic 0.12.0

A syntactic diffing tool
Documentation 
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<p align="center">
  <a href="#readme"><img src="img/logo.png" alt="it's difftastic!"/></a>
  <br>
  <a href="https://crates.io/crates/difftastic"><img src="https://img.shields.io/crates/v/difftastic.svg" alt="crates.io"></a>
  <a href="https://codecov.io/gh/Wilfred/difftastic"><img src="https://codecov.io/gh/Wilfred/difftastic/branch/master/graph/badge.svg?token=dZzAZtQT2S" alt="codecov.io"></a>
  <a href="http://difftastic.wilfred.me.uk/"><img src="https://img.shields.io/badge/manual-mdBook-brightgreen" alt="manual"></a>
</p>


Difftastic is an experimental structured diff tool that compares files
based on their syntax.

See [the manual](http://difftastic.wilfred.me.uk/) to get started.

## Screenshots

![Rust screenshot](img/rust.png)

![C screenshot](img/c.png)

![Haskell screenshot](img/haskell.png)

<!--
To regenerate these screenshots:

$ git clone git@github.com:rust-itertools/itertools.git
$ cd itertools
$ GIT_EXTERNAL_DIFF=difft git show --ext-diff 38805c6a882a9f00615078250ccc8c070c3a214d

$ git clone git@github.com:stedolan/jq.git
$ cd jq
$ GIT_EXTERNAL_DIFF=difft git show --ext-diff 6306ac89667cf35f47ddc40aa0630546c57e387f

$ git clone git@github.com:xmonad/xmonad.git
$ cd xmonad
$ GIT_EXTERNAL_DIFF=difft git show --ext-diff 6d661203d39e44d1dc2aa3a930381e6711d26d56

-->

## Languages

Difftastic supports the following languages:

* C
* C++
* C#
* Clojure
* CSS
* Elixir
* Emacs Lisp
* Go
* Haskell
* Java
* JavaScript (and JSX)
* JSON
* OCaml
* Python
* Rust
* TypeScript (and TSX)

If a file has an unrecognised extension, difftastic uses a
line-oriented diff.

## Known Issues

Performance. Difftastic scales relatively poorly on files with a large
number of changes, and can use a lot of memory. This might be solved
by A* search.

Display. Difftastic has a side-by-side display which usually works well, but can
be confusing.

Diff accuracy. Some delimiter moves are currently ignored (see
[#30](https://github.com/Wilfred/difftastic/issues/30)).

Integration. Difftastic only has [limited
support](http://difftastic.wilfred.me.uk/getting_started.html#git-external-diffs)
for git and mercurial today.

## Non-goals

Patch files. If you want to create a patch that you can later apply,
use `diff`. Difftastic ignores whitespace, so its output is
lossy. (AST patching is also a hard problem.)

## License

Difftastic is open source under the MIT license, see LICENSE for more
details.

Files in `sample_files/` are also under the MIT license unless stated
otherwise in their header.

## Further Reading

The [wiki](https://github.com/Wilfred/difftastic/wiki) includes
additional notes on alternative diffing techniques and tools.