README.md

Properly update an error's properties.

Features

• Prevents overriding error core properties (name, message, etc.)
• Protects against prototype pollution
• Merges deeply
• Merges with either high or low priority
• Copies another error's properties
• Strict, deep TypeScript typing of the return value

Examples

Error core properties

import setErrorProps from 'set-error-props'

const error = new Error('one')
setErrorProps(error, { message: 'two' })
console.log(error.message) // 'one'

Prototype pollution

const error = new Error('one')
setErrorProps(error, { toString: () => 'injected' })
console.log(error.toString()) // 'Error: one'
console.log(Error.prototype.toString()) // 'Error'

Deep merging

// Deep merges plain objects and arrays
const error = new Error('message')
error.prop = { one: [true] }
setErrorProps(error, { prop: { one: [false], two: true } })
console.log(error.prop) // { one: [true, false], two: true }

Low priority merging

const error = new Error('message')
error.prop = { one: true }
setErrorProps(error, { prop: { one: false, two: true } }, { soft: true })
console.log(error.prop) // { one: true, two: true }

Error copy

const error = new Error('one')
const secondError = new Error('two')
secondError.prop = true
setErrorProps(error, secondError)
console.log(error.message) // 'one'
console.log(error.prop) // true

Install

npm install set-error-props

This package is an ES module and must be loaded using an import or import() statement, not require().

API

setErrorProps(error, props, options?)

error Error | object
props Error | object
options Options?
Return value: Error

Assigns props to error, then returns error.

Options

Optional object with the following properties.

soft

Type: boolean
Default: false

Whether props should have lower merging priority over error or not.

Related projects

• modern-errors: Handle errors like it's 2022 🔮
• error-custom-classes: Create multiple error classes
• error-custom-class: Create one error class
• error-class-utils: Utilities to properly create error classes
• error-serializer: Convert errors to/from plain objects
• normalize-exception: Normalize exceptions/errors
• set-error-class: Properly update an error's class
• set-error-message: Properly update an error's message
• merge-error-cause: Merge an error with its cause
• error-cause-polyfill: Polyfill error.cause
• handle-cli-error: 💣 Error handler for CLI applications 💥
• log-process-errors: Show some ❤ to Node.js process errors

Support

For any question, don't hesitate to submit an issue on GitHub.

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Contributing

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