CustomPatch

Patch a buggy NPM package without forking it.

Based on the handy diff package (there is a jsdiff published on the NPM registry but it is a bogus one)

WHY

This tool does what patch-package does (or more accurately - should be doing) but without the related issues:

it works faster, especially when creating the patch
it never chokes on its own patches
it does not break if you try to apply a patch more than once (but shows a warning)
it does not require/depend on GIT
it does not require a lockfile present when creating patches

When you have made a bugfix for one of your dependencies but the author/maintainers refuse to accept your PR - you do not need to fork the package. Create a patch and seamlessly apply it locally for all your builds.

Installation

npm install custompatch -g

Setup

It operates in exactly the same way as patch-package so you can use the same setup if you have it already. Add the following to your package.json

"scripts": 
{
  "prepare": "custompatch"
}

Usage

Making patches

Open your IDE and make the required changes for the bugfix inside your dependency in node_modules. After that run

custompatch "name-of-the-buggy-package"

This will create a folder called patches inside your project and a file called name-of-the-buggy-package#version.patch in this folder. This file will be a unified diff between your fixed version of the dependency and its original code.

You can specify more than 1 package on the command-line - but no command-line options are accepted.

Updating patches

The process is exactly the same as for creating a patch for the first time.

Applying patches

Run custompatch without arguments inside your project folder - it will apply all the patches from patches folder. Currently there is no possibility to apply only the patch for a specific dependency. Also, it is not yet possible to undo a patch. Perhaps the command-line utility patch can do the job but this has not been tested:

patch -p1 -i patches/package-name#2.5.16.patch

Benefits of patching over forking

Forks often require extra build steps - and even more often you do not need this overhead
CustomPatch warns you when a patch was not applied cleanly - so that you can check that your fix is still valid for the new version of dependency
Keep your patches colocated with the code that depends on them
Patches can be reviewed as part of your normal review process, forks probably can't

License

Software License Agreement (BSD License)

Redistribution and use of this software in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
Neither the name of TMCDOS nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

tmcdos / custompatch

readme