unipatch
Apply unified diffs in memory, compatible with GNU patch.
A quick example:
>>> import textwrap
>>> import unipatch
>>> patch = textwrap.dedent(
... """\
... @@ -1,2 +1,3 @@
... apples
... bananas
... +cherries
... """
... )
>>> print(unipatch.apply_patch("apples\nbananas\n", patch))
apples
bananas
cherriesInstallation
Use pip:
python -m pip install unipatchPython 3.10 to 3.15 supported.
API
apply_patch(source: str, patch: str, forwards: bool=True)
Apply the unified diff in the string patch to the string source and return the resulting string. Pass forwards=False to apply the patch in reverse, undoing it instead.
Raises PatchError if the patch cannot be parsed or does not apply.
>>> unipatch.apply_patch("a\nb\n", "@@ -1 +1 @@\n-a\n+c\n")
'c\nb\n'
>>> unipatch.apply_patch("c\nb\n", "@@ -1 +1 @@\n-a\n+c\n", forwards=False)
'a\nb\n'PatchError
The base exception class, a subclass of ValueError. It has two subclasses:
PatchParseError: the patch is not valid unified diff format.
HunkApplyError: the patch parsed, but a hunk’s lines do not match the source.
Exception messages name the failing hunk and what went wrong.
Behaviour
unipatch follows the behaviour of the GNU patch commandline utility, verified by differentially testing against it with randomized inputs:
Hunks may apply at an offset from the line numbers stated in their @@ headers, matching by content, with a found offset carrying forward to later hunks.
A fuzz factor ignores up to two mismatching context lines at the edges of a hunk. Ignored context lines are left as they are in the source. A hunk with less context on one side, as diff produces at the start or end of a file, only applies at that edge of the source.
Oddities are tolerated like GNU patch:
Hunks cut short at the end of the patch
Context lines that have lost their leading space (empty and tab-led lines)
\ No newline at end of file markers
Only unified diff format is supported, not the older context or ed formats. Hence the name is unipatch.
1 maintainer
Metadata
1 maintainer
Release files for unipatch 1.0.1
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| unipatch-1.0.1.tar.gz | 8.7 kB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| unipatch-1.0.1-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 17.6 kB
Release files / unipatch-1.0.1.tar.gz
| Download URL | unipatch-1.0.1.tar.gz |
|---|---|
| Size | 8.7 kB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
876199e2ca3e74fb45afa6fb15caf8a5f076556dbecc3fc4864488bfe3b2b07f
|
|
BLAKE2b-256 checksum How to use checksums |
812e6e2bce2bd3dbb78db45f1820f9c1288e702395346a13c0e11ae3ff005f5c
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.13
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Sep 3, 2026.
Transparency logRelease files / unipatch-1.0.1-py3-none-any.whl
| Download URL | unipatch-1.0.1-py3-none-any.whl |
|---|---|
| Size | 8.9 kB |
| Tags | Python 3 |
|
SHA-256 checksum How to use checksums |
1994cec00483584ba13290a0745b6c81cf6bb0e557a77ffdfaed668c59ed4218
|
|
BLAKE2b-256 checksum How to use checksums |
e5e3a0da2ea893901615f43caeb0d7613bc60b9c4d7140ab20f3ec745f9ecf45
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.13
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Sep 3, 2026.
Transparency log
