Registry / testing / remark-lint-no-duplicate-headings

remark-lint-no-duplicate-headings

library4.0.1jsnpmunverified

remark-lint rule to warn when headings with equivalent text appear in a Markdown document. Current stable version is 4.0.1. Part of the remark-lint ecosystem, this plugin is ESM-only, requires Node.js 16+, and is included in the `remark-preset-lint-markdown-style-guide` preset. It helps screen reader users and prevents fragile automatic heading IDs. Unlike custom checks, it integrates directly with unified pipelines and CLI.

testing

npm install remark-lint-no-duplicate-headings

github ↗package ↗

INSTALL

IMPORT

SIG · REMARK-LINT-NO-DUP

remark-lint-no-duplicate-headings

testingjavascriptv4.0.1

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.

remarkLintNoDuplicateHeadings

✓ import remarkLintNoDuplicateHeadings from 'remark-lint-no-duplicate-headings'

✗ const remarkLintNoDuplicateHeadings = require('remark-lint-no-duplicate-headings')

Package is ESM-only since v3; CommonJS require will fail.

remarkLintNoDuplicateHeadings

✓ import remarkLintNoDuplicateHeadings from 'remark-lint-no-duplicate-headings'

✗ import { remarkLintNoDuplicateHeadings } from 'remark-lint-no-duplicate-headings'

Default export, not named.

Type definitions

✓ No type imports needed; types are shipped with package.

✗ Attempting to import types separately like `import type { Options } from 'remark-lint-no-duplicate-headings'`

The plugin accepts no options, so no types are exported.

Runs linting on example.md, reporting duplicate headings. ESM-only, Node 16+.

import { unified } from 'unified' import remarkParse from 'remark-parse' import remarkStringify from 'remark-stringify' import remarkLint from 'remark-lint' import remarkLintNoDuplicateHeadings from 'remark-lint-no-duplicate-headings' import { read } from 'to-vfile' import { reporter } from 'vfile-reporter' const file = await unified() .use(remarkParse) .use(remarkLint) .use(remarkLintNoDuplicateHeadings) .use(remarkStringify) .process(await read('example.md')) console.error(reporter(file))

remark --version

Debug

Known issues

breakingPackage is ESM-only since v3; CommonJS require() will throw.

fix

Use import syntax or dynamic import().

affects: >=3.0.0

gotchaPlugin accepts no options; attempting to pass options will be ignored.

fix

Remove any options object from .use(remarkLintNoDuplicateHeadings).

affects: >=1.0.0

gotchaComparison is case-sensitive and includes leading/trailing whitespace; headings that differ only in case or whitespace are not flagged.

fix

Ensure exact text match for detection.

affects: >=1.0.0

Errors

Common errors & fixes

Error [ERR_REQUIRE_ESM]: require() of ES Module

Using CommonJS require() on an ESM-only package.

fix

Switch to ESM imports or use dynamic import().

TypeError: (0 , remarkLintNoDuplicateHeadings) is not a function

Importing named export instead of default.

fix

Use `import remarkLintNoDuplicateHeadings from 'remark-lint-no-duplicate-headings'`.

Upgrade

Version history

4.0.1latest on npm

Audit

Dependencies

unifiedrequiredPeer dependency for integration with remark-lint pipeline

remark-lintrequiredRequired to register and run lint rules

Agent activity

2 hits · last 30 days

node

Resources

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

packagehttps://www.npmjs.com/package/remark-lint-no-duplicate-headings ↗