react-fast-compare

The fastest deep equal comparison for React, perfect for shouldComponentUpdate, also really fast at general-purpose deep comparison. This is a fork of the brilliant fast-deep-equal with some extra handling for React.

(Check out the benchmarking details.)

Install

$ yarn add react-fast-compare
# or
$ npm install 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

Usage

const isEqual = require('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() {
    // ...
  }
}

Benchmarking

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.

Generic Data

react-fast-compare x 161,872 ops/sec ±1.18% (82 runs sampled)
fast-deep-equal x 159,889 ops/sec ±1.62% (85 runs sampled)
lodash.isEqual x 30,750 ops/sec ±2.02% (86 runs sampled)
nano-equal x 35,608 ops/sec ±1.55% (86 runs sampled)
shallow-equal-fuzzy x 94,141 ops/sec ±1.80% (89 runs sampled)
  fastest: react-fast-compare,fast-deep-equal

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.

React and Generic Data

react-fast-compare x 150,667 ops/sec ±1.86% (83 runs sampled)
fast-deep-equal x 510 ops/sec ±1.67% (77 runs sampled)
lodash.isEqual x 25,760 ops/sec ±1.63% (83 runs sampled)
nano-equal x 629 ops/sec ±2.43% (80 runs sampled)
shallow-equal-fuzzy x 454 ops/sec ±1.42% (79 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.

Running Benchmarks

$ yarn install
$ yarn run benchmark

License

MIT

Contributing

Please see our contributions guide.