vfile-message

Create vfile messages.

Contents

• What is this?
• When should I use this?
• Install
• Use
• API
  • VFileMessage(reason[, place][, origin])
  • Well-known
• Types
• Compatibility
• Contribute
• License

What is this?

This package provides a (lint) message format.

When should I use this?

In most cases, you can use file.message from VFile itself, but in some cases you might not have a file, and still want to emit warnings or errors, in which case this can be used directly.

Install

This package is ESM only. In Node.js (version 14.14+ and 16.0+), install with npm:

npm install vfile-message

In Deno with esm.sh:

import {VFileMessage} from 'https://esm.sh/vfile-message@3'

In browsers with esm.sh:

<script type="module">
  import {VFileMessage} from 'https://esm.sh/vfile-message@3?bundle'
</script>

Use

import {VFileMessage} from 'vfile-message'

const message = new VFileMessage(
  'Unexpected unknown word `braavo`, did you mean `bravo`?',
  {line: 1, column: 8},
  'spell:typo'
)

console.log(message)

Yields:

[1:8: Unexpected unknown word `braavo`, did you mean `bravo`?] {
  reason: 'Unexpected unknown word `braavo`, did you mean `bravo`?',
  line: 1,
  column: 8,
  source: 'spell',
  ruleId: 'typo',
  position: {start: {line: 1, column: 8}, end: {line: null, column: null}}
}

API

This package exports the identifier VFileMessage. There is no default export.

VFileMessage(reason[, place][, origin])

Create a message for reason at place from origin.

When an error is passed in as reason, the stack is copied.

Parameters

• reason (string or Error) — reason for message, uses the stack and message of the error if given
• place (Node, Position, or Point, optional) — place in file where the message occurred
• origin (string, optional) — place in code where the message originates (example: 'my-package:my-rule' or 'my-rule')

Extends

Error.

Returns

Instance of VFileMessage.

Fields

• reason (string) — reason for message (you should use markdown)
• fatal (boolean | null | undefined) — state of problem; true marks associated file as no longer processable (error); false necessitates a (potential) change (warning); null | undefined for things that might not need changing (info)
• line (number | null) — starting line of error
• column (number | null) — starting column of error
• position (Position | null) — full unist position
• source (string | null, example: 'my-package') — namespace of message
• ruleId (string | null, example: 'my-rule') — category of message
• stack (string | null) — stack of message in code
• file (string | null) — path of a file (used throughout the VFile ecosystem)

Well-known

It’s OK to store custom data directly on the VFileMessage, some of those are handled by utilities. The following fields are documented and typed here.

Fields

• actual (string | null) — specify the source value that’s being reported, which is deemed incorrect
• expected (Array<string> | null) — suggest acceptable values that can be used instead of actual
• url (string | null) — link to docs for the message (this must be an absolute URL that can be passed as x to new URL(x))
• note (string | null) — long form description of the message (you should use markdown)

Types

This package is fully typed with TypeScript. It exports no additional types.

Compatibility

Projects maintained by the unified collective are compatible with all maintained versions of Node.js. As of now, that is Node.js 14.14+ and 16.0+. Our projects sometimes work with older versions, but this is not guaranteed.

Contribute

See contributing.md in vfile/.github for ways to get started. See support.md for ways to get help.

This project has a code of conduct. By interacting with this repository, organization, or community you agree to abide by its terms.

License

MIT © Titus Wormer