Faker::CreditCard creates fake credit card numbers and PhoneNumber::ddd creates fake ddds (brazilian) for testing

credit_card.rb

# Complement to Faker gem to create credit card number

# Usage:
#  > Faker::CreditCard.visa
#    => "4916287009378994"
#
# Card support:
# visa, master, amex, discover, diners, en_route, jcb, voyager

# Inspired by: http://www.darkcoding.net/credit-card/luhn-formula/
module Faker

  class InexistentCardTypeError < ArgumentError; end

  class CreditCard
    class << self

      def number(type, size = DEFAULT_SIZE)
        raise InexistentCardTypeError unless PREFIXES.include? type
        prefix = PREFIXES[type].sample
        number = prefix.to_s.split(//).map(&:to_i)
        number << rand(0..9) while number.size < size - 1
        number << check_digit(number)
        number.join
      end

      def method_missing(m)
        begin
          number(m)
        rescue InexistentCardTypeError
          super
        end
      end

      def cvv
        rand(100..999)
      end

      def expire_date
        (Time.now + rand(80000000..200000000)).strftime('%m/%y')
      end

      def type
        PREFIXES.keys.sample
      end

      def sample
        type = self.type

        {
          type:        type,
          number:      send(type),
          cvv:         cvv,
          expire_date: expire_date,
        }
      end

      private
        DEFAULT_SIZE = 16

        def check_digit(number)
          sum = 0
          number.reverse.each_with_index do |digit, index|
            # remeber indexes starts with 0!!!
            if index.even?
              digit *= 2
              digit -= 9 if digit > 9
            end
            sum += digit
          end
          ((sum / 10 + 1) * 10 - sum) % 10
        end
    end
    PREFIXES = {
      visa:         [4539, 4556, 4916, 4532, 4929, 40240071, 4485, 4716, 4],
      mastercard:   [51, 52, 53, 54, 55],
      amex:         [34, 37],
      discover:     [6011],
      diners:       [300, 301, 302, 303, 36, 38],
      en_route:     [2014, 2149],
      jcb:          [3088, 3096, 3112, 3158, 3337, 3528],
      voyager:      [8699],
    }

  end
end

phone_number.rb

module Faker
  class PhoneNumber
    class << self

      def ddd
        DDD.sample
      end
    end
    DDD = [11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 24, 27, 28, 31, 32, 33,
           34, 35, 37, 38, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 53, 54, 55,
           61, 62, 63, 64, 65, 66, 67, 68, 69, 71, 73, 74, 75, 77, 79, 81, 82,
           83, 84, 85, 86, 87, 88, 89, 91, 92, 93, 94, 95, 96, 97, 98]
  end
end

https://groups.google.com/g/fake-credit-card can i share this at here ?