---
id: unidiff
version: "1.0.0"
license: MIT
license_treatment: permissive
maintenance: active
---

# unidiff — Unified diff parsing/metadata extraction library.

License: permissive · Maintenance: active · Popularity: top 1,000 on PyPI

## Install

pip install unidiff
uv add unidiff
poetry add unidiff

## Description

# Unidiff

Simple Python library to parse and interact with unified diff data.

[![CI](https://github.com/matiasb/python-unidiff/actions/workflows/ci.yml/badge.svg)](https://github.com/matiasb/python-unidiff/actions/workflows/ci.yml)

## Installing unidiff

```console
$ pip install unidiff
```

## Quick start

```python
>>> import urllib.request
>>> from unidiff import PatchSet
>>> diff = urllib.request.urlopen('https://github.com/matiasb/python-unidiff/pull/3.diff')
>>> encoding = diff.headers.get_charsets()[0]
>>> patch = PatchSet(diff, encoding=encoding)
>>> patch
<PatchSet: [<PatchedFile: .gitignore>, <PatchedFile: unidiff/patch.py>, <PatchedFile: unidiff/utils.py>]>
>>> patch[0]
<PatchedFile: .gitignore>
>>> patch[0].is_added_file
True
>>> patch[0].added
6
>>> patch[1]
<PatchedFile: unidiff/patch.py>
>>> patch[1].added, patch[1].removed
(20, 11)
>>> len(patch[1])
6
>>> patch[1][2]
<Hunk: @@ 109,14 110,21 @@ def __repr__(self):>
>>> patch[2]
<PatchedFile: unidiff/utils.py>
>>> print(patch[2])
diff --git a/unidiff/utils.py b/unidiff/utils.py
index eae63e6..29c896a 100644
--- a/unidiff/utils.py
+++ b/unidiff/utils.py
@@ -37,4 +37,3 @@
 # - deleted line
 # \ No newline case...

## AI interpretation — verify before relying

Parses and inspects unified diff format data, exposing file changes, hunks, and line-level metadata for programmatic analysis or transformation.

Verdict: Stable, dependency-free library for diff parsing with active maintenance, no known vulnerabilities, and permissive licensing. Well-suited for tools that need to analyze or transform patch data.

[View on SkillFed](https://skillfed.io/packages/unidiff) · [View on PyPI](https://pypi.org/project/unidiff/)