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Properly update an error's message.

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.message`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/message).
However, if `error.message` is modified, `error.stack` might not be updated and
still contain the previous message.

This library fixes it by setting `error.message` while updating `error.stack`
accordingly. This works on any JavaScript engine.

# Example

Without `set-error-message`:

```js
const error = new Error('one')
console.log(error.message) // 'one'
console.log(error.stack) // 'Error: one ...'

error.message = 'two'
console.log(error.message) // 'two'
console.log(error.stack) // 'Error: one ...'
```

With `set-error-message`:

```js
import setErrorMessage from 'set-error-message'

const error = new Error('one')
console.log(error.message) // 'one'
console.log(error.stack) // 'Error: one ...'

setErrorMessage(error, 'two')
console.log(error.message) // 'two'
console.log(error.stack) // 'Error: two ...'
```

# Install

```bash
npm install set-error-message
```

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

## setErrorMessage(error, newMessage)

`error` `Error | any`\
`newMessage` `string`\
_Return value_: `Error`

Sets `error.message = newMessage`.

Returns `error`. If `error` is not an `Error` instance, it is converted to one.

# 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
- [`merge-error-cause`](https://github.com/ehmicky/merge-error-cause): Merge an
  error with its `cause`
- [`set-error-class`](https://github.com/ehmicky/set-error-class): Properly
  update an error's class
- [`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
- [`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!







