feat: usage of ESM modules imports (instead of CommonJS)

Fixes #10

BREAKING CHANGE: This package is now pure ESM

BREAKING CHANGE: minimum supported Node.js >= 22.0.0

.github/workflows/lint.yml

@@ -10,10 +10,10 @@ jobs:
   lint:
     runs-on: "ubuntu-latest"
     steps:
-      - uses: "actions/checkout@v4.1.7"
+      - uses: "actions/checkout@v4.2.2"
 
       - name: "Setup Node.js"
-        uses: "actions/setup-node@v4.0.3"
+        uses: "actions/setup-node@v4.1.0"
         with:
           node-version: "lts/*"
           cache: "npm"
@@ -30,6 +30,6 @@ jobs:
   commitlint:
     runs-on: "ubuntu-latest"
     steps:
-      - uses: "actions/checkout@v4.1.7"
+      - uses: "actions/checkout@v4.2.2"
 
-      - uses: "wagoid/commitlint-github-action@v6.1.2"
+      - uses: "wagoid/commitlint-github-action@v6.2.0"

.github/workflows/release.yml

@@ -13,13 +13,13 @@ jobs:
       pull-requests: "write"
       id-token: "write"
     steps:
-      - uses: "actions/checkout@v4.1.7"
+      - uses: "actions/checkout@v4.2.2"
         with:
           fetch-depth: 0
           persist-credentials: false
 
       - name: "Setup Node.js"
-        uses: "actions/setup-node@v4.0.3"
+        uses: "actions/setup-node@v4.1.0"
         with:
           node-version: "lts/*"
           cache: "npm"

.github/workflows/test.yml

@@ -10,10 +10,10 @@ jobs:
   test:
     runs-on: "ubuntu-latest"
     steps:
-      - uses: "actions/checkout@v4.1.7"
+      - uses: "actions/checkout@v4.2.2"
 
       - name: "Setup Node.js"
-        uses: "actions/setup-node@v4.0.3"
+        uses: "actions/setup-node@v4.1.0"
         with:
           node-version: "lts/*"
           cache: "npm"

README.md

@@ -66,7 +66,7 @@ Contributions are welcome to improve the rule, and to alleviate these limitation
 
 ## Prerequisites
 
-[Node.js](https://nodejs.org/) >= 16.0.0
+[Node.js](https://nodejs.org/) >= 22.0.0
 
 ## Installation
 

package.json

@@ -18,6 +18,8 @@
     "markdownlint-rule"
   ],
   "main": "src/index.js",
+  "types": "src/index.d.ts",
+  "type": "module",
   "files": [
     "src"
   ],
@@ -26,7 +28,7 @@
     "provenance": true
   },
   "engines": {
-    "node": ">=16.0.0"
+    "node": ">=22.0.0"
   },
   "scripts": {
     "lint:editorconfig": "editorconfig-checker",
@@ -42,19 +44,19 @@
   },
   "devDependencies": {
     "@types/markdown-it": "14.1.2",
-    "@types/node": "22.9.0",
+    "@types/node": "22.10.2",
     "editorconfig-checker": "6.0.0",
-    "eslint": "9.14.0",
-    "eslint-config-conventions": "17.0.0",
-    "eslint-plugin-promise": "7.1.0",
-    "eslint-plugin-unicorn": "56.0.0",
-    "eslint-plugin-import-x": "4.4.0",
-    "globals": "15.12.0",
-    "markdownlint": "0.36.1",
-    "markdownlint-cli2": "0.15.0",
-    "prettier": "3.3.3",
-    "semantic-release": "23.1.1",
-    "typescript-eslint": "8.13.0",
-    "typescript": "5.6.3"
+    "eslint": "9.17.0",
+    "eslint-config-conventions": "18.0.0",
+    "eslint-plugin-promise": "7.2.1",
+    "eslint-plugin-unicorn": "56.0.1",
+    "eslint-plugin-import-x": "4.6.1",
+    "globals": "15.14.0",
+    "markdownlint": "0.37.2",
+    "markdownlint-cli2": "0.17.0",
+    "prettier": "3.4.2",
+    "semantic-release": "24.2.0",
+    "typescript-eslint": "8.18.2",
+    "typescript": "5.7.2"
   }
 }

src/index.d.ts

@@ -0,0 +1,5 @@
+import type { Rule } from "markdownlint"
+
+declare const relativeLinksRule: Rule
+
+export default relativeLinksRule

src/index.js

@@ -1,10 +1,8 @@
-"use strict"
+import { pathToFileURL } from "node:url"
+import fs from "node:fs"
 
-const { pathToFileURL } = require("node:url")
-const fs = require("node:fs")
-
-const { filterTokens } = require("./markdownlint-rule-helpers/helpers.js")
-const {
+import { filterTokens } from "./markdownlint-rule-helpers/helpers.js"
+import {
   convertHeadingToHTMLFragment,
   getMarkdownHeadings,
   getMarkdownIdOrAnchorNameFragments,
@@ -12,14 +10,14 @@ const {
   getNumberOfLines,
   getLineNumberStringFromFragment,
   lineFragmentRe,
-} = require("./utils.js")
+} from "./utils.js"
 
 /** @typedef {import('markdownlint').Rule} MarkdownLintRule */
 
 /**
  * @type {MarkdownLintRule}
  */
-const customRule = {
+const relativeLinksRule = {
   names: ["relative-links"],
   description: "Relative links should be valid",
   tags: ["links"],
@@ -172,4 +170,4 @@ const customRule = {
   },
 }
 
-module.exports = customRule
+export default relativeLinksRule

src/markdownlint-rule-helpers/helpers.js

@@ -14,7 +14,7 @@
  * @param {(token: MarkdownItToken) => void} handler Callback function.
  * @returns {void}
  */
-const filterTokens = (params, type, handler) => {
+export const filterTokens = (params, type, handler) => {
   for (const token of params.parsers.markdownit.tokens) {
     if (token.type === type) {
       handler(token)
@@ -28,11 +28,6 @@ const filterTokens = (params, type, handler) => {
  * @param {string} name HTML attribute name.
  * @returns {RegExp} Regular Expression for matching.
  */
-const getHtmlAttributeRe = (name) => {
+export const getHtmlAttributeRe = (name) => {
   return new RegExp(`\\s${name}\\s*=\\s*['"]?([^'"\\s>]*)`, "iu")
 }
-
-module.exports = {
-  filterTokens,
-  getHtmlAttributeRe,
-}

src/utils.js

@@ -1,10 +1,10 @@
-const MarkdownIt = require("markdown-it")
+import MarkdownIt from "markdown-it"
 
-const { getHtmlAttributeRe } = require("./markdownlint-rule-helpers/helpers.js")
+import { getHtmlAttributeRe } from "./markdownlint-rule-helpers/helpers.js"
 
 const markdownIt = new MarkdownIt({ html: true })
 
-const lineFragmentRe = /^#(?:L\d+(?:C\d+)?-L\d+(?:C\d+)?|L\d+)$/
+export const lineFragmentRe = /^#(?:L\d+(?:C\d+)?-L\d+(?:C\d+)?|L\d+)$/
 
 /**
  * Converts a Markdown heading into an HTML fragment according to the rules
@@ -14,7 +14,7 @@ const lineFragmentRe = /^#(?:L\d+(?:C\d+)?-L\d+(?:C\d+)?|L\d+)$/
  * @param {string} inlineText Inline token for heading.
  * @returns {string} Fragment string for heading.
  */
-const convertHeadingToHTMLFragment = (inlineText) => {
+export const convertHeadingToHTMLFragment = (inlineText) => {
   return (
     "#" +
     encodeURIComponent(
@@ -40,7 +40,7 @@ const ignoredTokens = new Set(["heading_open", "heading_close"])
  * @param {string} content
  * @returns {string[]}
  */
-const getMarkdownHeadings = (content) => {
+export const getMarkdownHeadings = (content) => {
   const tokens = markdownIt.parse(content, {})
 
   /** @type {string[]} */
@@ -88,7 +88,7 @@ const idHTMLAttributeRegex = getHtmlAttributeRe("id")
  * @param {string} content
  * @returns {string[]}
  */
-const getMarkdownIdOrAnchorNameFragments = (content) => {
+export const getMarkdownIdOrAnchorNameFragments = (content) => {
   const tokens = markdownIt.parse(content, {})
 
   /** @type {string[]} */
@@ -128,7 +128,7 @@ const getMarkdownIdOrAnchorNameFragments = (content) => {
  * @example isValidIntegerString("1abc") // false
  * @example isValidIntegerString("1.0") // false
  */
-const isValidIntegerString = (value) => {
+export const isValidIntegerString = (value) => {
   const regex = /^\d+$/
   return regex.test(value)
 }
@@ -138,7 +138,7 @@ const isValidIntegerString = (value) => {
  * @param {string} content
  * @returns {number}
  */
-const getNumberOfLines = (content) => {
+export const getNumberOfLines = (content) => {
   return content.split("\n").length
 }
 
@@ -148,16 +148,6 @@ const getNumberOfLines = (content) => {
  * @returns {string}
  * @example getLineNumberStringFromFragment("#L50") // 50
  */
-const getLineNumberStringFromFragment = (fragment) => {
+export const getLineNumberStringFromFragment = (fragment) => {
   return fragment.slice(2)
 }
-
-module.exports = {
-  lineFragmentRe,
-  convertHeadingToHTMLFragment,
-  getMarkdownHeadings,
-  getMarkdownIdOrAnchorNameFragments,
-  isValidIntegerString,
-  getNumberOfLines,
-  getLineNumberStringFromFragment,
-}

test/index.test.js

@@ -1,9 +1,9 @@
-const { test } = require("node:test")
-const assert = require("node:assert/strict")
+import { test } from "node:test"
+import assert from "node:assert/strict"
 
-const { markdownlint } = require("markdownlint").promises
+import * as markdownlint from "markdownlint/promise"
 
-const relativeLinksRule = require("../src/index.js")
+import relativeLinksRule from "../src/index.js"
 
 /**
  *
@@ -11,7 +11,7 @@ const relativeLinksRule = require("../src/index.js")
  * @returns
  */
 const validateMarkdownLint = async (fixtureFile) => {
-  const lintResults = await markdownlint({
+  const lintResults = await markdownlint.lint({
     files: [fixtureFile],
     config: {
       default: false,

test/utils.test.js

@@ -1,14 +1,14 @@
-const { test } = require("node:test")
-const assert = require("node:assert/strict")
+import { test } from "node:test"
+import assert from "node:assert/strict"
 
-const {
+import {
   convertHeadingToHTMLFragment,
   getMarkdownHeadings,
   getMarkdownIdOrAnchorNameFragments,
   isValidIntegerString,
   getNumberOfLines,
   getLineNumberStringFromFragment,
-} = require("../src/utils.js")
+} from "../src/utils.js"
 
 test("utils", async (t) => {
   await t.test("convertHeadingToHTMLFragment", async () => {