jonschlinkert / merge-deep

Recursively merge values in a JavaScript object.

merge-deep

Recursively merge values in a javascript object.

Please consider following this project's author, Jon Schlinkert, and consider starring the project to show your ❤️ and support.

Install

Install with npm:

$ npm install --save merge-deep

Based on mout's implementation of merge

Usage

var merge = require('merge-deep');

merge({a: {b: {c: 'c', d: 'd'}}}, {a: {b: {e: 'e', f: 'f'}}});
//=> { a: { b: { c: 'c', d: 'd', e: 'e', f: 'f' } } }

About

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Running Tests

Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

$ npm install && npm test

Building docs

(This project's readme.md is generated by verb, please don't edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)

To generate the readme, run the following command:

$ npm install -g verbose/verb#dev verb-generate-readme && verb

Related projects

You might also be interested in these projects:

• assign-deep: Deeply assign the values of all enumerable-own-properties and symbols from one or more source objects… more | homepage
• defaults-deep: Like extend but recursively copies only the missing properties/values to the target object. | homepage
• extend-shallow: Extend an object with the properties of additional objects. node.js/javascript util. | homepage
• merge-deep: Recursively merge values in a javascript object. | homepage
• mixin-deep: Deeply mix the properties of objects into the first object. Like merge-deep, but doesn't clone… more | homepage
• omit-deep: Recursively omit the specified key or keys from an object. | homepage

Contributors

Commits	Contributor
32	jonschlinkert
8	doowb

Author

Jon Schlinkert

• GitHub Profile
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• LinkedIn Profile

License

Copyright © 2021, Jon Schlinkert. Released under the MIT License.

---

This file was generated by verb-generate-readme, v0.8.0, on January 11, 2021.

merge-deep's Issues

Misuse of CommonJS

From webpack:

WARNING in ./node_modules/merge-deep/utils.js
7:34-41 Critical dependency: require function is used in a way in which dependencies cannot be statically extracted
 @ ./node_modules/merge-deep/utils.js
 @ ./node_modules/merge-deep/index.js

security contact

Hi,

The GitHub Security Lab is attempting to reach a security contact for this project. Please drop us a line at [email protected] with reference GHSL-2020-160.

Kind regards,
Bas Alberts
GitHub Security Lab

webpack support

I got the error:

 WARNING in ./node_modules/merge-deep/utils.js
    7:34-41 Critical dependency: require function is used in a way in which dependencies cannot be statically extracted
     @ ./node_modules/merge-deep/utils.js
     @ ./node_modules/merge-deep/index.js

Why is this 2x the size of mixin-deep?

Is there any functional difference between,

  // 3.5Kb
  result = mergeDeep(obj1, obj2)

  // 1.1Kb
  result = mixinDeep({}, obj1, obj2)

Symbols are ignored

Symbols can be used as property keys, but they are ignored.

const merge = require('merge-deep');

const mySymbol = Symbol('mySymbol');

const x = { value: 42, [mySymbol]: 'hello' };

console.log(x);
// { value: 42, [Symbol(mySymbol)]: 'hello' }

const y = { other: 33 };
const z = merge(x, y);

console.log(z);
// { value: 42, other: 33 }
// expected: { value: 42, [Symbol(mySymbol)]: 'hello', other: 33 }

notUnion property for arrays

Can specify which array fields will be replaced (instead of concatenated with union). Few lines in code and all tests working.

module.exports = function mergeDeep(orig, objects, notUnionParams) {

if (isObject(val) || Array.isArray(val)) {
     merge(target, val, notUnionParams);
}

function merge(target, obj, notUnionParams) {
var notUnion = false;

if((notUnionParams !== undefined) && (notUnionParams.length > 0) && ((notUnionParams.indexOf(key) > -1) || (notUnionParams == key))){
     notUnion = true;
}

if (isObject(newVal) && isObject(oldVal)) {
     target[key] = merge(newVal, oldVal, notUnionParams);
} else if (Array.isArray(newVal)) {
     if(notUnion){
          target[key] = union([], newVal);  
     } else {
          target[key] = union([], newVal, oldVal);
     }
} else {
     target[key] = clone(oldVal);
}

And the test

it('should correctly use not union property', function() {
    var obj1 = {a: {
      "a": [{
        1: 1,2: 2
      }]
    }};
    var obj2 = {a: {
      "a": [{
        1: 2,2: 3
      }]
    }};

    var actual = merge(obj1, obj2, ["a"]);
    console.log(actual.a);
    assert.deepEqual(actual.a, { a: [{ 1:1,2:2 }] });
});

is-plain-object

Is there a reason for restricting this to plain objects?

Cannot find module 'kind-of'

Cannot find module 'kind-of'

doesn't browserify

The use of lazy-cache breaks browserify's ability to build this module. Would you accept pull requests to drop lazy-cache from merge-deep and clone-deep?

Cannot find module kind-of

encountered this problem with fresh node_modules

bundling with webpack against [email protected]

relevant issue with recent reports #4

Does Array values concat instead of be replaced?

I'm not sure, if this a bug or a feature. Look:

import merge from 'merge-deep';

const object1 = { a: '1', b: '2', c: [1, 2, 3] };
const object2 = { a: undefined, b: null, c: null }; // 'c' property might be anything else, like '1', or undefined, or an empty Array, doesn't matter

const mergedObject = merge(object1, object2);
console.log(mergedObject);
=> { a: undefined, b: null, c: [1, 2, 3] } // So, the last property is not changed.

If 'c' in the object2 was 'abc', we'll get

=> { a: undefined, b: null, c: ['abc', 1, 2, 3] }

It looks like Array type values concat, instead of be replaced with a new value. But I need a tool to replace values while merging.

Should I use assign-deep instead? Cause the last one does it well.

Properties containing functions aren't replaced like numbers and other data types

• OS: Debian 9.
• Node version: 6.3.1.
• Library version: 3.0.0.

Why should properties containing functions behave differently from, say, numbers?

• Consider: mergeDeep({ a: () => 1, b: () => 2 }, { b: () => 3, c: () => 4 }).b()
• Expected: 3
• Got: 2

vs.

• Consider: mergeDeep({ a: 1, b: 2 }, { b: 3, c: 4 }).b
• Expected: 3
• Got: 3