@visulima/deep-clone

Visulima Deep Clone

Really Fast Deep Clone.

^{Daniel Bannert's open source work is supported by the community on GitHub Sponsors}

Install

npm install @visulima/deep-clone

yarn add @visulima/deep-clone

pnpm add @visulima/deep-clone

Usage

Copy or deep clone an input value to an arbitrary depth. The function accepts both objects and primitives.

import deepClone from "@visulima/deep-clone";

const cloned = deepClone({ a: 1, b: { c: 2 } });

console.log(cloned); // => {a: 1, b: {c: 2}}

API

deepClone(input, options?)

input

Type: any

The input value to copy.

options

Type: object

strict

Type: boolean

Default: false

If true, it will copy all properties, including non-enumerable ones and symbols.

handlers

Type: object

A set of custom handlers for specific type of value. Each handler is a function that takes the original value and returns a new value or throws an error if the value is not supported.

Array: InternalHandler<unknown[]>;
ArrayBuffer: InternalHandler;
Blob: InternalHandler;
DataView: InternalHandler;
Date: InternalHandler;
Error: InternalHandler;
Float32Array: InternalHandler;
Float64Array: InternalHandler;
Int8Array: InternalHandler;
Int16Array: InternalHandler;
Int32Array: InternalHandler;
Map: InternalHandler<Map<unknown, unknown>>;
Object: InternalHandler<Record<string, unknown>>;
Promise: InternalHandler<Promise>;
RegExp: InternalHandler;
Set: InternalHandler<Set>;
WeakMap: InternalHandler<WeakMap<any, unknown>>;
WeakSet: InternalHandler<WeakSet>;

Utils

copyOwnProperties(input)

Copy all properties contained on the object.

import { copyOwnProperties } from "@visulima/deep-clone/utils";

const obj = { a: 1, b: 2 };

const copy = copyOwnProperties(obj);

console.log(copy); // => {a: 1, b: 2}

getCleanClone(input)

Get an empty version of the object with the same prototype it has.

import { getCleanClone } from "@visulima/deep-clone/utils";

const obj = { a: 1, b: 2 };

const clean = getCleanClone(obj);

console.log(clean); // => {}

Notes

List of supported values/types:
- undefined (original value is returned)
- null (original value is returned)
- boolean/Boolean (original value is returned)
- string/String (original value is returned)
- number/Number (original value is returned)
- function
- Object
- Date
- RegExp
- Set
- Map
- Error
- URIError
- ReferenceError
- SyntaxError
- RangeError
- EvalError
- TypeError
- System Error (Node.js)
- Array
- Int8Array
- Uint8Array
- Uint8ClampedArray
- Init16Array
- Uint16Array
- Int32Array
- Uint32Array
- Float32Array
- Float64Array
- Buffer (Node.js)
- DataView
- Blob
List of unsupported values/types:
- DOMElement: to copy DOM elements, use element.cloneNode().
- Symbol
- WeakMap
- WeakSet
- File
- FileList
- ImageData
- ImageBitmap
- Promise
- SharedArrayBuffer
The implementation can handle circular references.
If a Number, String, or Boolean object is encountered, the value is cloned as a primitive. This behavior is intentional. The implementation is opinionated in wanting to avoid creating numbers, strings, and booleans via the new operator and a constructor.
The implementation only checks whether basic Objects, Arrays, and class instances are extensible, sealed, and/or frozen.
functions are not cloned; their reference is copied.
The implementation supports custom error types which are Error instances (e.g., ES2015 subclasses).

Benchmarks

Note:

It is true that jsondiffpatch.clone() from jsondiffpatch is faster than @visulima/deep-clonse in this particular benchmark, but it cannot handle as many situations as @visulima/deep-clonse can.

It is true that fastest-json-copy is faster than @visulima/deep-clonse in this particular benchmark. Also, fastest-json-copy has such huge limitations that it is rarely useful. For example, it treats things like Date and Map instances the same as empty {}. It can't handle circular references.

plain-object-clone is also really limited in capability.

Supported Node.js Versions

Libraries in this ecosystem make the best effort to track Node.js’ release schedule. Here’s a post on why we think this is important.

Contributing

If you would like to help take a look at the list of issues and check our Contributing guild.

Note: please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.

Credits

License

The visulima deep-clone is open-sourced software licensed under the MIT

@visulima/deep-clone