react-fast-compare

The fastest deep equal comparison for React. Really fast general-purpose deep comparison.
Great forshouldComponentUpdate. This is a fork of the brilliant
fast-deep-equal with some
extra handling for React.

[![Travis Status][trav_img]][trav_site]
[![AppVeyor Status][appveyor_img]][appveyor_site]
[![npm version][npm_img]][npm_site]
[![size_minzip][size_minzip]][size_site]
[![size_min][size_min]][size_site]

!benchmark chart

(Check out the benchmarking details.)

Install

``sh
$ yarn add @luchanso/react-fast-compare


or


$ npm install @luchanso/react-fast-compare
`

Highlights

- ES5 compatible; works in node.js (0.10+) and browsers (IE9+)
- deeply compares any value (besides objects with circular references)
- handles React-specific circular references, like elements
- checks equality Date and RegExp objects
- should be just as fast as fast-deep-equal for general use, and faster for React use
- small: under 600 bytes minified+gzipped

Usage

`jsx
const isEqual = require("@luchanso/react-fast-compare");

// general usage
console.log(isEqual({ foo: "bar" }, { foo: "bar" })); // true

// react usage
class ExpensiveRenderer extends React.Component {
shouldComponentUpdate(nextProps) {
return !isEqual(this.props, nextProps);
}
render() {
// ...
}
}
`

Or like Hight ordered component

`jsx
const performance = require("@luchanso/react-fast-compare").performance;

class ExpensiveRenderer extends React.Component {
render() {
// ...
}
}

export default performance()(ExpensiveRenderer);
`

Do I Need shouldComponentUpdate?

> What's faster than a really fast deep comparison? No deep comparison at all.

—This Readme

Deep checks in React's shouldComponentUpdate should not be used blindly.
First, see if a
PureComponent
would work for you. If it won't (if you need deep checks), it's wise to make
sure you've correctly indentified the bottleneck in your application by
profiling the performance.
After you've determined that you _do_ need deep equality checks and you've
identified the minimum number of places to apply them, then this library may
be for you! For more information about making your app faster, check out the
Optimizing Performance
section of the React docs.

Benchmarking this Library

All tests carried out locally on a MacBook. The absolute values are much less
important than the relative differences between packages.

Benchmarking source can be found
here.
Each "operation" consists of running all relevant tests. The React benchmark
uses both the generic tests and the react tests; these runs will be slower
simply because there are more tests in each operation.

$3

`
react-fast-compare x 207,503 ops/sec ±0.54% (92 runs sampled)
fast-deep-equal x 195,006 ops/sec ±0.70% (91 runs sampled)
lodash.isEqual x 43,778 ops/sec ±0.55% (91 runs sampled)
nano-equal x 198,036 ops/sec ±0.37% (95 runs sampled)
shallow-equal-fuzzy x 173,023 ops/sec ±0.59% (95 runs sampled)
fastest: react-fast-compare
`

react-fast-compare and fast-deep-equal should be the same speed for these
tests; any difference is just noise. react-fast-compare won't be faster than
fast-deep-equal, because it's based on it.

$3

`
react-fast-compare x 187,628 ops/sec ±0.58% (93 runs sampled)
fast-deep-equal x 477 ops/sec ±0.55% (91 runs sampled)
lodash.isEqual x 35,100 ops/sec ±0.16% (95 runs sampled)
nano-equal x 468 ops/sec ±0.53% (94 runs sampled)
shallow-equal-fuzzy x 684 ops/sec ±0.43% (92 runs sampled)
fastest: react-fast-compare
`

Three of these packages cannot handle comparing React elements (which are
circular): fast-deep-equal, nano-equal, and shallow-equal-fuzzy.

$3

`sh
$ yarn install
$ yarn run benchmark
``

fast-deep-equal Versioning

react-fast-compare@3.0.0 tracks fast-deep-equal@2.0.1

License

MIT

Contributing

Please see our contributions guide.

[trav_img]: https://api.travis-ci.org/FormidableLabs/react-fast-compare.svg
[trav_site]: https://travis-ci.org/FormidableLabs/react-fast-compare
[cov_img]: https://img.shields.io/coveralls/FormidableLabs/react-fast-compare.svg
[cov_site]: https://coveralls.io/r/FormidableLabs/react-fast-compare
[npm_img]: https://badge.fury.io/js/react-fast-compare.svg
[npm_site]: http://badge.fury.io/js/react-fast-compare
[appveyor_img]: https://ci.appveyor.com/api/projects/status/github/formidablelabs/react-fast-compare?branch=master&svg=true
[appveyor_site]: https://ci.appveyor.com/project/FormidableLabs/react-fast-compare
[size_min]: https://img.shields.io/bundlephobia/min/react-fast-compare.svg
[size_minzip]: https://img.shields.io/bundlephobia/minzip/react-fast-compare.svg
[size_site]: https://bundlephobia.com/result?p=react-fast-compare