# set-error-class > Properly update an error's class Latest version **3.0.1** (published 2025-03-29) · MIT license · 0 weekly downloads ## Install ```sh npm install set-error-class pnpm add set-error-class yarn add set-error-class bun add set-error-class ``` ## Health **Score 55/100 (C)** — status: stable. Positive: has types; esm support; no vulnerabilities; high maintenance score; high quality score. Warnings: low downloads. Negative: stale. ## Facts | | | |---|---| | Version | 3.0.1 | | Published | 2025-03-29 | | First published | 2022-08-31 | | Weekly downloads | 0 | | License | MIT | | TypeScript types | bundled | | Module format | ESM + CommonJS | | Node | >=18.18.0 | | Dependencies | 1 | | Unpacked size | 13.7 KB | | Known vulnerabilities | 0 | | Install scripts | no | | GitHub stars | 4 | | Author | ehmicky | | Maintainers | ehmicky | ## Links - npm: https://www.npmjs.com/package/set-error-class - Repository: https://github.com/ehmicky/set-error-class - Homepage: https://www.github.com/ehmicky/set-error-class - Issues: https://github.com/ehmicky/set-error-class/issues - npm.io page: https://npm.io/package/set-error-class ## Dependencies (1) - [normalize-exception](https://npm.io/package/normalize-exception.md) ^4.0.1 ## Recent versions - 3.0.1 (latest) — 2025-03-29 - 3.0.0 — 2023-10-28 - 2.0.0 — 2023-05-13 - 1.6.0 — 2022-12-12 - 1.5.0 — 2022-11-21 - 1.4.0 — 2022-11-11 - 1.3.0 — 2022-11-07 - 1.2.1 — 2022-10-13 - 1.2.0 — 2022-10-13 - 1.1.0 — 2022-08-31 - 1.0.1 — 2022-08-31 - 1.0.0 — 2022-08-31 - 0.0.1 — 2022-08-31 ## README [![Node](https://img.shields.io/badge/-Node.js-808080?logo=node.js&colorA=404040&logoColor=66cc33)](https://www.npmjs.com/package/set-error-class) [![Browsers](https://img.shields.io/badge/-Browsers-808080?logo=firefox&colorA=404040)](https://unpkg.com/set-error-class?module) [![TypeScript](https://img.shields.io/badge/-Typed-808080?logo=typescript&colorA=404040&logoColor=0096ff)](/src/main.d.ts) [![Codecov](https://img.shields.io/badge/-Tested%20100%25-808080?logo=codecov&colorA=404040)](https://codecov.io/gh/ehmicky/set-error-class) [![Minified size](https://img.shields.io/bundlephobia/minzip/set-error-class?label&colorA=404040&colorB=808080&logo=webpack)](https://bundlephobia.com/package/set-error-class) [![Mastodon](https://img.shields.io/badge/-Mastodon-808080.svg?logo=mastodon&colorA=404040&logoColor=9590F9)](https://fosstodon.org/@ehmicky) [![Medium](https://img.shields.io/badge/-Medium-808080.svg?logo=medium&colorA=404040)](https://medium.com/@ehmicky) Properly update an error's class. # Features - Sets an error's [prototype, name and constructor](#seterrorclasserror-errorclass) - Update the [error's `stack`](#errorstack) with its new `name` - Handles [invalid errors](#invalid-errors) # Example ```js import setErrorClass from 'set-error-class' const typeError = new TypeError('test') console.log(typeError instanceof TypeError) // true console.log(typeError.name) // 'TypeError' console.log(typeError.constructor) // TypeError console.log(typeError.stack) // TypeError: test ... const rangeError = setErrorClass(typeError, RangeError) console.log(rangeError === typeError) // true console.log(rangeError instanceof RangeError) // true console.log(rangeError.name) // 'RangeError' console.log(rangeError.constructor) // RangeError console.log(rangeError.stack) // RangeError: test ... ``` # Install ```bash npm install set-error-class ``` This package works in both Node.js >=18.18.0 and [browsers](https://raw.githubusercontent.com/ehmicky/dev-tasks/main/src/browserslist). This is an ES module. It must be loaded using [an `import` or `import()` statement](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c), not `require()`. If TypeScript is used, it must be configured to [output ES modules](https://www.typescriptlang.org/docs/handbook/esm-node.html), not CommonJS. # API ## setErrorClass(error, ErrorClass) `error` `Error | unknown`\ `ErrorClass` `typeof Error`\ _Return value_: `Error` Sets the `error`'s [prototype](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/getPrototypeOf), [`name`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/name) and [`constructor`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/constructor). # Usage ## Invalid errors `error` is returned. If `error` is not an `Error` instance, it is converted to one. ## `error.stack` In V8 (Chrome, Node.js, Deno, etc.), [`error.stack`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/stack) includes [`error.name`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/message). It is updated accordingly. ## Error constructors `ErrorClass` is assigned to `error`, but its constructor is not called. In some instances, this might lead to invalid errors. If `ErrorClass`'s constructor is doing anything significant, that logic should be performed on `error` as well. # Related projects - [`modern-errors`](https://github.com/ehmicky/modern-errors): Handle errors in a simple, stable, consistent way - [`error-custom-class`](https://github.com/ehmicky/error-custom-class): Create one error class - [`error-class-utils`](https://github.com/ehmicky/error-class-utils): Utilities to properly create error classes - [`error-serializer`](https://github.com/ehmicky/error-serializer): Convert errors to/from plain objects - [`normalize-exception`](https://github.com/ehmicky/normalize-exception): Normalize exceptions/errors - [`is-error-instance`](https://github.com/ehmicky/is-error-instance): Check if a value is an `Error` instance - [`set-error-message`](https://github.com/ehmicky/set-error-message): Properly update an error's message - [`wrap-error-message`](https://github.com/ehmicky/wrap-error-message): Properly wrap an error's message - [`set-error-props`](https://github.com/ehmicky/set-error-props): Properly update an error's properties - [`set-error-stack`](https://github.com/ehmicky/set-error-stack): Properly update an error's stack - [`merge-error-cause`](https://github.com/ehmicky/merge-error-cause): Merge an error with its `cause` - [`error-cause-polyfill`](https://github.com/ehmicky/error-cause-polyfill): Polyfill `error.cause` - [`handle-cli-error`](https://github.com/ehmicky/handle-cli-error): 💣 Error handler for CLI applications 💥 - [`log-process-errors`](https://github.com/ehmicky/log-process-errors): Show some ❤ to Node.js process errors - [`error-http-response`](https://github.com/ehmicky/error-http-response): Create HTTP error responses - [`winston-error-format`](https://github.com/ehmicky/winston-error-format): Log errors with Winston # Support For any question, _don't hesitate_ to [submit an issue on GitHub](../../issues). Everyone is welcome regardless of personal background. We enforce a [Code of conduct](CODE_OF_CONDUCT.md) in order to promote a positive and inclusive environment. # Contributing This project was made with ❤️. The simplest way to give back is by starring and sharing it online. If the documentation is unclear or has a typo, please click on the page's `Edit` button (pencil icon) and suggest a correction. If you would like to help us fix a bug or add a new feature, please check our [guidelines](CONTRIBUTING.md). Pull requests are welcome! --- _Source: https://npm.io/package/set-error-class · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._