three-way-merge

A javascript library for performing three-way diffs and merges on text. Based closely on dyph in ruby. An implementation of Paul Heckel's two-way diff algorithm.

This library works similar to git merge: imagine you have a text document, and you share it with a friend, then make some changes. Your friend also makes some changes, now you need to resolve the differences and merge the two changed documents together. If you just compare your changed document to your friend's changed document, it will be impossible to tell whether each of you made additions or deletions. But if you compare both changed documents to your original document, you can compute a diff for each and combine the diffs together.

Installation

npm install --save three-way-merge

Usage

import merge from 'three-way-merge';

const base =     [1, 2, 3, 4, 5, 6].join("\n");
const left =     [   2, 3, 4, 5, 6].join("\n");
const right =    [1, 2, 3, 4, 9, 6].join("\n");

const merged = merge(base, left, right);

console.log(merged.conflict);      => false
console.log(merged.joinedResult()) => (merged string)

License (The MIT License)

Copyright 2017 Movable, Inc Portions Copyright 2016 Boundless

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.