Lists line numbers of code blocks without info string in markdown files

checker.js

// Lists line numbers of code blocks without info string
// Usage: node checker.js */**/*.md

const fs = require('fs')
const commonmark = require('commonmark')

function* eachCodeBlocks(parsed) {
  const walker = parsed.walker()
  let event, node
  while ((event = walker.next())) {
    node = event.node
    if (event.entering && node.type === 'code_block') {
      yield node
    }
  }
}

process.argv.slice(2).forEach((path) => {
  const reader = new commonmark.Parser()
  const parsed = reader.parse(fs.readFileSync(path).toString())
  for (const node of eachCodeBlocks(parsed)) {
    if (!node.info) {
      console.log(`${path}:${node.sourcepos[0][0]}`)
    }
  }
})