Overview

react-merge - function that merge 2 (or more) objects in a proper "react"-way. I.e. if second object doesn't change first then the result object is strictly equals first object.

import { merge } from 'react-merge';

let firstObject = { "a": 1, "b": { "c": 2, "d": 3 } }
let result = merge(firstObject, { "a": 1 });
console.log(result === firstObject); // true

result = merge(firstObject, { "a": 2, "b": { "c": 2 } });
console.log(result === firstObject); // false
console.log(result.b === firstObject.b); // true

Installation

To install the stable version:

npm install --save react-merge

Usage

import { merge } from 'react-merge'

Documentation

merge(objectA: any, objectB: any, options: MergeOptions)

Merges objectA with objectB in react-way.

If objectB is not mergeable then objectA is returned as result.

If objectA is not mergeable then new object deeply equal to objectB is returned as result.

If both are not mergeable then empty object is returned.

If objectA is array and objectB is not array then the result is array with props of objectB.

options - object with following properties:

• path?: string | any[] - // path in first object that should be merged with second object
• replace?: replaceType - force replace for mergeable object instead of merge, can be boolean, object with boolean or function props or a function of the following type (path: any[], objectA: anyObject, objectB: anyObject) => boolean
• arrays?: Function - function to merge arrays of the following type (path: any[], arrayA: any[], arrayB: any[]) => any[]. Example, to concat arrays (t, a, b) => a.concat(b), to replace (t, a, b) => b
• del?: boolean - remove props with MergeOptions.delSymbol
• delSymbol?: any - symbol that marks props that should be removed if MergeOptions.del is true, default is undefined
• noSymbol?: boolean - if true, then skips symbol props in objects
• diff?: boolean - if true then first object is changed in the way to be deeply equal to the second.

merge.all(objectA: any, objectsB: any[], options: MergeOptions)

Merges objectA with objectsB array.

Examples:

merge array with object

import { merge } from 'react-merge';

let firstObject = { "a": [0, 1, 2, 3] }
let secondObject = { "a": { "1": 11, "length": 2 } };
let result = merge(firstObject, secondObject);
console.log(result); // {"a": [0, 11]}

default array merging

import { merge } from 'react-merge';

let firstObject = { "a": [0, 1, 2, 3] }
let secondObject = { "a": [] };
secondObject.a[2] = 22;
secondObject.a.length = 5;
let result = merge(firstObject, secondObject);
console.log(result); // {"a": [0, 1, 22, 3, undefined]}

del options

import { merge } from 'react-merge';

let firstObject = { "a": 1, "b": { "c": 2, "d": 3 } }
let secondObject = { "a": undefined };
let result = merge(firstObject, secondObject, { del: true });
console.log(result); // {"b": {"c":2, "d":3}}

result = merge(firstObject, secondObject, { del: false });
console.log(result); // {"a": undefined, "b": {"c":2, "d":3}}

diff options

import { merge } from 'react-merge';

const firstObject = { "a": 1, "b": { "c": 2, "d": 3 } }
const secondObject = { "a": 1 };
const result = merge(firstObject, secondObject, { diff: true });

console.log(result === firstObject); // false
console.log(result === secondObject); // false
console.log(result); // {"a": 1}