multi-diff v1.0.1

multi-diff

This tool allows to compute the difference between objects. There are plenty of other excellent tools to get the difference between objects, but most of them only work on two objects. This tool allows to compute the difference between however many objects you'd like.

The objects that are passed to diff() need to have an id property of type string or number. The ids are used to be able to tell which value belongs to which object.

Installation

yarn add multi-diff

or

npm i multi-diff

Usage

This tool can be used in both node and browser environments.

import { diff } from 'multi-diff';
// const { diff } = require('multi-diff');

const result = diff(
  {
    id: 0,
    prop1: 13,
    prop2: 'value'
  },
  {
    id: 1,
    prop1: 42,
    prop2: 'value'
  },
  {
    id: 'some-id',
    prop1: 7,
    prop2: 'value'
  }
);
// result = { prop1: { 0: 13, 1: 42, 'some-id': 7 } }

Nested objects

diff internally uses a Set to keep track of property values (essentially a === comparison) so nested objects are shown as difference if they don't refer to the same object.

const a = {
  id: 0,
  prop1: { key: 'value' },
  prop2: 13
};

const b = {
  id: 1,
  prop1: { key: 'value' },
  prop2: 13
}

diff(a, b); // { prop1: { 0: { key: 'value' }, 1: { key: 'value' } } }

// shared object
const o = { key: 'value' };

const x = {
  id: 0,
  prop1: o,
  prop2: 13
};

const y = {
  id: 1,
  prop1: o,
  prop2: 42
};

diff(x, y); // { prop2: { 0: 13, 1: 42 } }

Test

Run the tests with

yarn test

or

npm test