@httpx/plain-object

Fast and lightweight (~80B) functions to check or assert that a value is a plain object.

A plain object is a basic JavaScript object, such as {}, { data: [] }, new Object() or Object.create(null).

See how it compares to other libraries.

Install

$ npm install @httpx/plain-object
$ yarn add @httpx/plain-object
$ pnpm add @httpx/plain-object

Features

• 👉  Provide isPlainObject and assertPlainObject functions.
• 🦄  Convenience PlainObject typescript typings.
• 🚀  Faster than most alternatives, see benchmarks.
• 📐  Lightweight (starts at ~80B)
• 🛡️  Tested on node 18-22, browser, cloudflare workers and runtime/edge.
• 🙏  Cross-realms tolerant (node:vm runInNewContext,...)
• 🗝️  Available in ESM and CJS formats.

Documentation

👉 Official website or GitHub Readme

Usage

isPlainObject

import { isPlainObject } from '@httpx/plain-object';

// ✅👇 True
isPlainObject({ });                       // ✅
isPlainObject({ key: 'value' });          // ✅
isPlainObject({ key: new Date() });       // ✅
isPlainObject(new Object());              // ✅
isPlainObject(Object.create(null));       // ✅
isPlainObject({ nested: { key: true} });  // ✅
isPlainObject(new Proxy({}, {}));         // ✅
isPlainObject({ [Symbol('tag')]: 'A' });  // ✅

// ✅👇 (node context, workers, ...)
const runInNewContext = await import('node:vm').then(
    (mod) => mod.runInNewContext
);
isPlainObject(runInNewContext('({})'));   // ✅

// ✅👇 Static built-in classes are treated as plain objects
//       check for `isStaticBuiltInClass` to exclude if needed

isPlainObject(Math);                // ✅
isPlainObject(JSON);                // ✅
isPlainObject(Atomics);             // ✅

// ❌👇 False

class Test { };
isPlainObject(new Test())           // ❌
isPlainObject(10);                  // ❌
isPlainObject(null);                // ❌
isPlainObject('hello');             // ❌
isPlainObject([]);                  // ❌
isPlainObject(new Date());          // ❌
isPlainObject(new Uint8Array([1])); // ❌
isPlainObject(Buffer.from('ABC'));  // ❌
isPlainObject(Promise.resolve({})); // ❌
isPlainObject(Object.create({}));   // ❌
isPlainObject(new (class Cls {}));  // ❌
isPlainObject(globalThis);          // ❌,

assertPlainObject

import { assertPlainObject } from '@httpx/plain-object';
import type { PlainObject } from '@httpx/plain-object';

function fn(value: unknown) {

    // 👇 Throws `new TypeError('Not a PlainObject')` if not a plain object
    assertPlainObject(value);

    // 👇 Throws `new TypeError('Custom message')` if not a plain object
    assertPlainObject(value, 'Custom message');

    // 👇 Throws custom error if not a plain object
    assertPlainObject(value, () => {
        throw new HttpBadRequest('Custom message');
    });
    
    return value;
}

try {
    const value = fn({ key: 'value' });
    // ✅ Value is known to be PlainObject<unknown>
    assertType<PlainObject>(value);
} catch (error) {
    console.error(error);
}

isStaticBuiltInClass

info: Since v2.0.0

Since v2.0.0, isPlainObject will accept static built-in classes as plain objects (Math, JSON, Atomics). If you need to exclude them, a new typeguard has been created isStaticBuiltInClass.

import { isPlainObject, isStaticBuiltInClass } from '@httpx/plain-object';
const v = Math; // or Atomics or JSON
if (isPlainObject(v) && !isStaticBuiltInClass(v)) {
    console.log('v is a plain object but not a static built-in class');
}

PlainObject type

Generic

ìsPlainObject and assertPlainObject accepts a generic to provide type autocompletion. Be aware that no runtime check are done. If you're looking for runtime validation, check zod, valibot or other alternatives.

import { isPlainObject } from '@httpx/plain-object';
import type { PlainObject } from '@httpx/plain-object';

type CustomType = {
    id: number;
    data?: {
        test: string[];
        attributes?: {
            url?: string | null;
            caption?: string | null;
            alternativeText?: string | null;
        } | null;
    } | null;
};

const value = { id: 1 } as unknown;

if (isPlainObject<CustomType>(value)) {
   // ✅ Value is a PlainObject with typescript autocompletion
   // Note that there's no runtime checking of keys, so they are
   // `unknown | undefined`. They will require unsing `?.` to access. 
    
  const url = value?.data?.attributes?.url; // autocompletion works
  // ✅ url is `unknown | undefined`, so in order to use it, you'll need to
  //    manually check for the type.
  if (typeof url === 'string') {
      console.log(url.toUpperCase());
  }
}

PlainObject

import { assertPlainObject } from '@httpx/plain-object';
import type { PlainObject } from '@httpx/plain-object';

function someFn(value: PlainObject) {
  //    
}

const value = { key: 'value' } as unknown;
assertPlainObject(value);
someFn(value)

Benchmarks

Performance is continuously monitored thanks to codspeed.io.

 RUN  v2.1.2 /home/sebastien/github/httpx/packages/plain-object
 
 ✓ bench/comparative.bench.ts (7) 5269ms
   ✓ Compare calling isPlainObject with 110x mixed types values (7) 5267ms
     name                                                         hz     min     max    mean     p75     p99    p995    p999     rme  samples
   · @httpx/plain-object: `isPlainObject(v)`              948,266.97  0.0010  0.0700  0.0011  0.0011  0.0013  0.0017  0.0034  ±0.10%   474134   fastest
   · (sindresorhus/)is-plain-obj: `isPlainObj(v)`         796,997.41  0.0011  0.0718  0.0013  0.0012  0.0026  0.0028  0.0053  ±0.14%   398499
   · @sindresorhus/is: `is.plainObject(v)`                544,333.86  0.0017  0.0359  0.0018  0.0018  0.0032  0.0037  0.0083  ±0.11%   272167
   · estoolkit:  `isPlainObject(v)`                        87,689.00  0.0103  1.0569  0.0114  0.0112  0.0189  0.0208  0.0350  ±0.47%    43845
   · redux:  `isPlainObject(v)`                           257,141.86  0.0030  0.3135  0.0039  0.0038  0.0070  0.0094  0.0219  ±0.23%   128571
   · (jonschlinkert/)is-plain-object: `isPlainObject(v)`  403,749.92  0.0018  0.3947  0.0025  0.0024  0.0057  0.0083  0.0185  ±0.38%   201875
   · lodash-es: `_.isPlainObject(v)`                        9,949.41  0.0685  0.6957  0.1005  0.1101  0.1964  0.2144  0.2790  ±0.95%     4975   slowest


 BENCH  Summary

  @httpx/plain-object: `isPlainObject(v)` - bench/comparative.bench.ts > Compare calling isPlainObject with 110x mixed types values
    1.19x faster than (sindresorhus/)is-plain-obj: `isPlainObj(v)`
    1.74x faster than @sindresorhus/is: `is.plainObject(v)`
    2.35x faster than (jonschlinkert/)is-plain-object: `isPlainObject(v)`
    3.69x faster than redux:  `isPlainObject(v)`
    10.81x faster than estoolkit:  `isPlainObject(v)`
    95.31x faster than lodash-es: `_.isPlainObject(v)`

See benchmark file for details.

Bundle size

Bundle size is tracked by a size-limit configuration

| Scenario (esm) | Size (compressed) | |-------------------------------------------------------------|------------------:| | import { isPlainObject } from '@httpx/plain-object | ~ 80B | | import { assertPlainObject } from '@httpx/plain-object | ~ 134B | | Both isPlainObject and assertPlainObject | ~ 142B | | import { isStaticBuiltInClass } from '@httpx/plain-object | ~ 37B |

For CJS usage (not recommended) track the size on bundlephobia.

Compatibility

| Level | CI | Description | |------------|----|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Node | ✅ | CI for 18.x, 20.x & 22.x. | | Browser | ✅ | Tested with latest chrome (vitest/playwright) | | Browsers | ✅ | > 96% on 07/2024. Mins to Chrome 96+, Firefox 90+, Edge 19+, iOS 12+, Safari 12+, Opera 77+ | | Edge | ✅ | Ensured on CI with @vercel/edge-runtime. | | Cloudflare | ✅ | Ensured with @cloudflare/vitest-pool-workers (see wrangler.toml | | Typescript | ✅ | TS 5.0 + / are-the-type-wrong checks on CI. | | ES2022 | ✅ | Dist files checked with es-check | | Performance| ✅ | Monitored with codspeed.io |

For older browsers: most frontend frameworks can transpile the library (ie: nextjs...)

Comparison with other libraries

| Library | Compat | Perf | CJS+ESM | |----------------------------------------------------------------|-------------|--------------|---------|
| is-plain-obj | Differences | 1.09x slower | No | | es-toolkit | No | | Yes | | (@redux)isPlainObject | ✅ 100% | 2.80x slower | Yes |

redux/isPlainObject

100% compatible see tests.

@sindresorhus/is-plain-obj

This library wouldn't be possible without @sindresorhus is-plain-obj. Notable differences:

• [x] SLightly faster (10%)
• [x] ESM and CJS formats.
• [x] Named export.
• [x] Smaller bundle size.
• [x] Provide a PlainObject type and assertPlainObject function.
• [x] Typescript convenience PlainObject type.

Since v2, it diverges from is-plain-obj by

• [x] Static built-in classes are considered as plain objects (use isStaticBuiltInClass to exclude).
• [x] [Symbol.iterator] is considered as a valid property for plain objects.
• [x] [Symbol.toStringTag] is considered as a valid property for plain objects.`

Contributors

Contributions are welcome. Have a look to the CONTRIBUTING document.

Sponsors

If my OSS work brightens your day, let's take it to new heights together! Sponsor, coffee, or star – any gesture of support fuels my passion to improve. Thanks for being awesome! 🙏❤️

Special thanks to

License

MIT © belgattitude and contributors.