# has-proto

> Does this environment have the ability to get the [[Prototype]] of an object on creation with `__proto__`?

Latest version **1.2.0** (published 2024-12-06) · MIT license · 0 weekly downloads

> **Native alternative:** Always `true` — Use native JavaScript (Node 0.10.0+) (https://developer.mozilla.orgOperators/Object_initializer#prototype_setter)

## Install

```sh
npm install has-proto
pnpm add has-proto
yarn add has-proto
bun add has-proto
```

## Health

**Score 50/100 (C)** — status: stable.

Positive: has types; esm support; no vulnerabilities; high quality score.

Warnings: low downloads.

Negative: stale.

## Facts

| | |
|---|---|
| Version | 1.2.0 |
| Published | 2024-12-06 |
| First published | 2022-12-13 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Node | >= 0.4 |
| Dependencies | 1 |
| Unpacked size | 14.1 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 6 |
| Author | Jordan Harband |
| Maintainers | ljharb |
| Keywords | prototype, proto, set, get, __proto__, getPrototypeOf, setPrototypeOf, has |

## Links

- npm: https://www.npmjs.com/package/has-proto
- Repository: https://github.com/inspect-js/has-proto
- Homepage: https://github.com/inspect-js/has-proto#readme
- Issues: https://github.com/inspect-js/has-proto/issues
- Funding: https://github.com/sponsors/ljharb
- npm.io page: https://npm.io/package/has-proto

## Dependencies (1)

- [dunder-proto](https://npm.io/package/dunder-proto.md) ^1.0.0

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## Recent versions

- 1.2.0 (latest) — 2024-12-06
- 1.1.0 — 2024-12-01
- 1.0.3 — 2024-02-19
- 1.0.2 — 2024-02-19
- 1.0.1 — 2022-12-21
- 1.0.0 — 2022-12-13

## README

# has-proto <sup>[![Version Badge][npm-version-svg]][package-url]</sup>

[![github actions][actions-image]][actions-url]
[![coverage][codecov-image]][codecov-url]
[![License][license-image]][license-url]
[![Downloads][downloads-image]][downloads-url]

[![npm badge][npm-badge-png]][package-url]

Does this environment have the ability to set the [[Prototype]] of an object on creation with `__proto__`?

## Example

```js
var hasProto = require('has-proto');
var assert = require('assert');

assert.equal(typeof hasProto(), 'boolean');

var hasProtoAccessor = require('has-proto/accessor')();
if (hasProtoAccessor) {
	assert.equal([].__proto__, Array.prototype);
} else {
	assert(!('__proto__' in Object.prototype));
}

var hasProtoMutator = require('has-proto/mutator');
var obj = {};
assert('toString' in obj);

obj.__proto__ = null;
if (hasProtoMutator) {
	assert(!('toString' in obj));
} else {
	assert('toString' in obj);
	assert.equal(obj.__proto__, null);
}
```

## Tests
Simply clone the repo, `npm install`, and run `npm test`

[package-url]: https://npmjs.org/package/has-proto
[npm-version-svg]: https://versionbadg.es/inspect-js/has-proto.svg
[deps-svg]: https://david-dm.org/inspect-js/has-proto.svg
[deps-url]: https://david-dm.org/inspect-js/has-proto
[dev-deps-svg]: https://david-dm.org/inspect-js/has-proto/dev-status.svg
[dev-deps-url]: https://david-dm.org/inspect-js/has-proto#info=devDependencies
[npm-badge-png]: https://nodei.co/npm/has-proto.png?downloads=true&stars=true
[license-image]: https://img.shields.io/npm/l/has-proto.svg
[license-url]: LICENSE
[downloads-image]: https://img.shields.io/npm/dm/has-proto.svg
[downloads-url]: https://npm-stat.com/charts.html?package=has-proto
[codecov-image]: https://codecov.io/gh/inspect-js/has-proto/branch/main/graphs/badge.svg
[codecov-url]: https://app.codecov.io/gh/inspect-js/has-proto/
[actions-image]: https://img.shields.io/endpoint?url=https://github-actions-badge-u3jn4tfpocch.runkit.sh/inspect-js/has-proto
[actions-url]: https://github.com/inspect-js/has-proto/actions

---
_Source: https://npm.io/package/has-proto · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._