Add support to CNPJ

doc/unreleased/default/cnpj.md

@@ -0,0 +1,11 @@
+# Faker::CNPJ
+
+Brazilian CNPJ valid random generator.
+
+```ruby
+Faker::CNPJ.number
+#=> "00000000000"
+
+Faker::CNPJ.formatted
+#=> "000.000.000-00"
+```

lib/faker/default/cnpj.rb

@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+module Faker
+  class CNPJ < Faker::Base
+    attr_accessor :digits
+
+    def initialize
+      @digits = Array.new(8).map { Faker::Config.random.rand(0..9) }.concat([0, 0, 0, 1])
+    end
+
+    def number
+      @number ||= [*digits, first_digit, last_digit].join
+    end
+
+    def formatted
+      @formatted ||= '%s.%s.%s/%s-%s' % number.scan(/(\d{2})(\d{3})(\d{3})(\d{4})(\d{2})/).flatten
+    end
+
+    private
+
+    def first_digit
+      values = [5, 4, 3, 2, 9, 8, 7, 6, 5, 4, 3, 2]
+      sum = digits.map.with_index { |v, i| v * values[i] }.inject(&:+)
+      result = sum % 11
+      result < 2 ? 0 : 11 - result
+    end
+
+    def last_digit
+      values = [6, 5, 4, 3, 2, 9, 8, 7, 6, 5, 4, 3, 2]
+      sum = [*digits, first_digit].map.with_index { |v, i| v * values[i] }.inject(&:+)
+      result = sum % 11
+      result < 2 ? 0 : 11 - result
+    end
+
+    class << self
+      def number
+        new.number
+      end
+
+      def formatted
+        new.formatted
+      end
+    end
+  end
+end

test/faker/default/test_faker_cnpj.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require_relative '../../test_helper'
+
+class TestFakerCNPJ < Test::Unit::TestCase
+  def setup
+    @tester = Faker::CNPJ.new
+  end
+
+  def test_number
+    assert_equal(14, @tester.number.length)
+  end
+
+  def test_formatted
+    assert @tester.formatted.match(/\d{2}\.\d{3}\.\d{3}\/\d{4}-\d{2}/)
+  end
+end

unreleased_README.md

@@ -127,6 +127,7 @@ gem 'faker', :git => 'https://github.com/stympy/faker.git', :branch => 'master'
   - [Faker::Cannabis](doc/unreleased/default/cannabis.md)
   - [Faker::ChileRut](doc/unreleased/default/chile_rut.md)
   - [Faker::ChuckNorris](doc/unreleased/default/chuck_norris.md)
+  - [Faker::CNPJ](doc/unreleased/default/cnpj.md)
   - [Faker::Code](doc/unreleased/default/code.md)
   - [Faker::Coffee](doc/unreleased/default/coffee.md)
   - [Faker::Coin](doc/unreleased/default/coin.md)