'use strict' const { pathToFileURL } = require('node:url') const fs = require('node:fs') /** * Calls the provided function for each matching token. * * @param {Object} params RuleParams instance. * @param {string} type Token type identifier. * @param {Function} handler Callback function. * @returns {void} */ const filterTokens = (params, type, handler) => { for (const token of params.tokens) { if (token.type === type) { handler(token) } } } /** * Adds a generic error object via the onError callback. * * @param {Object} onError RuleOnError instance. * @param {number} lineNumber Line number. * @param {string} [detail] Error details. * @param {string} [context] Error context. * @param {number[]} [range] Column and length of error. * @param {Object} [fixInfo] RuleOnErrorFixInfo instance. * @returns {void} */ const addError = (onError, lineNumber, detail, context, range, fixInfo) => { onError({ lineNumber, detail, context, range, fixInfo }) } const EXTERNAL_PROTOCOLS = new Set([ 'http:', 'https:', 'mailto:', 'tel:', 'ftp:' ]) const customRule = { names: ['relative-links'], description: 'Relative links should be valid', tags: ['links'], function: (params, onError) => { filterTokens(params, 'inline', (token) => { token.children.forEach((child) => { const { lineNumber, type, attrs } = child if (type === 'link_open') { attrs.forEach((attr) => { if (attr[0] === 'href') { const href = attr[1] const url = new URL(href, pathToFileURL(params.name)) url.hash = '' const isRelative = href.startsWith('./') || href.startsWith('../') || !EXTERNAL_PROTOCOLS.has(url.protocol) if (isRelative && !fs.existsSync(url.pathname)) { const detail = `Link "${href}" is dead` addError(onError, lineNumber, detail) } } }) } }) }) } } module.exports = customRule