markdown-it/bin/markdown-it.mjs

#!/usr/bin/env node
/* eslint no-console:0 */

import fs from 'node:fs'
import argparse from 'argparse'
import markdownit from '../index.mjs'

const cli = new argparse.ArgumentParser({
  prog: 'markdown-it',
  add_help: true
})

cli.add_argument('-v', '--version', {
  action: 'version',
  version: JSON.parse(fs.readFileSync(new URL('../package.json', import.meta.url))).version
})

cli.add_argument('--no-html', {
  help: 'Disable embedded HTML',
  action: 'store_true'
})

cli.add_argument('-l', '--linkify', {
  help: 'Autolink text',
  action: 'store_true'
})

cli.add_argument('-t', '--typographer', {
  help: 'Enable smartquotes and other typographic replacements',
  action: 'store_true'
})

cli.add_argument('--trace', {
  help: 'Show stack trace on error',
  action: 'store_true'
})

cli.add_argument('file', {
  help: 'File to read',
  nargs: '?',
  default: '-'
})

cli.add_argument('-o', '--output', {
  help: 'File to write',
  default: '-'
})

const options = cli.parse_args()

function readFile (filename, encoding, callback) {
  if (options.file === '-') {
    // read from stdin
    const chunks = []

    process.stdin.on('data', function (chunk) { chunks.push(chunk) })

    process.stdin.on('end', function () {
      return callback(null, Buffer.concat(chunks).toString(encoding))
    })
  } else {
    fs.readFile(filename, encoding, callback)
  }
}

readFile(options.file, 'utf8', function (err, input) {
  let output

  if (err) {
    if (err.code === 'ENOENT') {
      console.error('File not found: ' + options.file)
      process.exit(2)
    }

    console.error(
      (options.trace && err.stack) ||
      err.message ||
      String(err))

    process.exit(1)
  }

  const md = markdownit({
    html: !options.no_html,
    xhtmlOut: false,
    typographer: options.typographer,
    linkify: options.linkify
  })

  try {
    output = md.render(input)
  } catch (e) {
    console.error(
      (options.trace && e.stack) ||
      e.message ||
      String(e))

    process.exit(1)
  }

  if (options.output === '-') {
    // write to stdout
    process.stdout.write(output)
  } else {
    fs.writeFileSync(options.output, output)
  }
})