Registry / testing / remark-lint-fenced-code-flag

remark-lint-fenced-code-flag

library4.2.0jsnpmunverified

A remark-lint rule that warns when fenced code blocks lack a language flag (infostring) or use an unrecognized one. Current stable version 4.2.0, released as part of the remark-lint monorepo with regular updates tied to remark ecosystem releases. Differentiates from generic linting by optionally validating against GitHub Linguist flags, ensuring code highlighting compatibility. Ships TypeScript definitions, ESM-only, requires Node.js 16+. Part of the remark-lint preset family.

testing

npm install remark-lint-fenced-code-flag

github ↗package ↗

INSTALL

IMPORT

SIG · REMARK-LINT-FENCED

remark-lint-fenced-code-flag

testingjavascriptv4.2.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

remarkLintFencedCodeFlag

✓ import remarkLintFencedCodeFlag from 'remark-lint-fenced-code-flag'

✗ const remarkLintFencedCodeFlag = require('remark-lint-fenced-code-flag')

Default export is the plugin function. ESM-only since v4; CommonJS require is not supported.

checkGithubLinguistFlag

✓ import { checkGithubLinguistFlag } from 'remark-lint-fenced-code-flag'

Exported utility function to validate a flag against GitHub Linguist list.

CheckFlag

✓ import type { CheckFlag } from 'remark-lint-fenced-code-flag'

TypeScript only. Available from v4.1.0+.

Options

✓ import type { Options } from 'remark-lint-fenced-code-flag'

TypeScript only. Represents options object type.

Demonstrates how to set up a unified pipeline with remark-lint and the fenced-code-flag rule, reading a markdown file, processing with options, and reporting lint warnings.

import { unified } from 'unified'; import remarkParse from 'remark-parse'; import remarkStringify from 'remark-stringify'; import remarkLint from 'remark-lint'; import remarkLintFencedCodeFlag from 'remark-lint-fenced-code-flag'; import { read } from 'to-vfile'; import { reporter } from 'vfile-reporter'; const file = await read('example.md'); await unified() .use(remarkParse) .use(remarkLint) .use(remarkLintFencedCodeFlag, { allowEmpty: false }) .use(remarkStringify) .process(file); console.error(reporter(file));

Debug

Known issues

breakingPackage is ESM-only since version 4.0.0.

fix

Use import statements. If required in CommonJS, use dynamic import() or downgrade to version 3.x.

affects: >=4.0.0

breakingNode.js version requirement raised to 16+ in v4.

fix

Update Node.js to version 16 or later.

affects: >=4.0.0

deprecatedThe built-in list of allowed flags may not be updated frequently; consider using the checkGithubLinguistFlag function for accurate validation.

fix

Use the checkGithubLinguistFlag imported utility to validate flags against GitHub Linguist.

affects: all

gotchaOptions can be passed as array, CheckFlag function, or Options object. Passing a string array directly is deprecated in favor of Options array property.

fix

Pass options as { allowEmpty: true, allowed: ['js', 'ts'] } for clarity.

affects: >=4.0.0

Errors

Common errors & fixes

Error [ERR_REQUIRE_ESM]: require() of ES Module /path/to/node_modules/remark-lint-fenced-code-flag/index.js from /path/to/file.js not supported.

Package is ESM-only from v4.

fix

Convert your project to ESM (use import/export) or use dynamic import: const m = await import('remark-lint-fenced-code-flag')

TypeError: Cannot read properties of undefined (reading 'type')

Missing 'remark-lint' in the unified pipeline.

fix

Ensure you have .use(remarkLint) before the rule: unified().use(remarkParse).use(remarkLint).use(remarkLintFencedCodeFlag)

Upgrade

Version history

4.2.0latest on npm

Audit

Dependencies

unifiedrequiredPlugin interface; must be used with unified pipeline.

remark-lintrequiredLint framework integration; required for the rule to function.

remark-parseoptionalMarkdown parser needed for converting source to AST.

remark-stringifyoptionalStringifier needed for output after linting (common in API usage).

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/remarkjs/remark-lint.git#main ↗

packagehttps://www.npmjs.com/package/remark-lint-fenced-code-flag ↗