@dohasys/lib-javascript-bra-cpf-cnpj/src/cnpj.js

Uma lib portando o código do repositório https://github.com/carvalhoviniciusluiz/cpf-cnpj-validator de typescript para javascript.

// Blacklist common values.
const BLACKLIST = [
  '00000000000000',
  '11111111111111',
  '22222222222222',
  '33333333333333',
  '44444444444444',
  '55555555555555',
  '66666666666666',
  '77777777777777',
  '88888888888888',
  '99999999999999'
]

const STRICT_STRIP_REGEX = /[-\\/.]/g
const LOOSE_STRIP_REGEX = /[^\d]/g

const verifierDigit = (digits) => {
  let index = 2
  const reverse = digits.split('').reduce((buffer, number) => {
    return [parseInt(number, 10)].concat(buffer)
  }, [])

  const sum = reverse.reduce((buffer, number) => {
    buffer += number * index
    index = (index === 9 ? 2 : index + 1)
    return buffer
  }, 0)

  const mod = sum % 11
  return (mod < 2 ? 0 : 11 - mod)
}

const strip = (number, strict = false) => {
  const regex = strict ? STRICT_STRIP_REGEX : LOOSE_STRIP_REGEX
  return (number || '').replace(regex, '')
}

const format = (number) => {
  return strip(number).replace(/^(\d{2})(\d{3})(\d{3})(\d{4})(\d{2})$/, '$1.$2.$3/$4-$5')
}

const isValid = (number, strict = false) => {
  const stripped = strip(number, strict)

  // CNPJ must be defined
  if (!stripped) {
    return false
  }

  // CNPJ must have 14 chars
  if (stripped.length !== 14) {
    return false
  }

  // CNPJ can't be blacklisted
  if (BLACKLIST.includes(stripped)) {
    return false
  }

  let numbers = stripped.substr(0, 12)
  numbers += verifierDigit(numbers)
  numbers += verifierDigit(numbers)

  return numbers.substr(-2) === stripped.substr(-2)
}

const generate = (formatted = false) => {
  let numbers = ''

  for (let i = 0; i < 12; i += 1) {
    numbers += Math.floor(Math.random() * 9)
  }

  numbers += verifierDigit(numbers)
  numbers += verifierDigit(numbers)

  return (formatted ? format(numbers) : numbers)
}

module.exports = {
  verifierDigit,
  strip,
  format,
  isValid,
  generate
}