Add Faker::Company.czech_organisation_number (faker-ruby#1101)

* Add czech_organisation_number support

* Add czech_organisation_number support

* Add czech_organisation_number support (docs)

* Update changelog.md

CHANGELOG.md

@@ -1,9 +1,10 @@
 # Change Log
 
 ## HEAD Unreleased
-### Latest update: 2018-06-01
+### Latest update: 2018-06-02
 
 ### Feature Request
+- [PR #1101](https://github.com/stympy/faker/pull/1101) Add Faker::Company.czech_organisation_number [@jindrichskupa](https://github.com/jindrichskupa)
 - [PR #1265](https://github.com/stympy/faker/pull/1265) Add Faker::WorldCup [@snayrouz](https://github.com/snayrouz)
 - [PR #1141](https://github.com/stympy/faker/pull/1141) Add Faker::Coffee.intensifier [@oyeanuj](https://github.com/oyeanuj)
 - [PR #1260](https://github.com/stympy/faker/pull/1260) Add Faker::Auto features to Faker::Vehicle [@mrstebo](https://github.com/mrstebo)

doc/company.md

@@ -33,6 +33,8 @@ Faker::Company.profession #=> "firefighter"
 
 Faker::Company.swedish_organisation_number #=> "7962578022"
 
+Faker::Company.czech_organisation_number #=> "77778171"
+
 Faker::Company.french_siren_number #=> "819489626"
 
 Faker::Company.french_siret_number #=> "81948962600013"

lib/faker/company.rb

@@ -71,6 +71,17 @@ def swedish_organisation_number
         base + luhn_algorithm(base).to_s
       end
 
+      def czech_organisation_number
+        sum = 0
+        base = []
+        [8, 7, 6, 5, 4, 3, 2].each do |weight|
+          base << sample((0..9).to_a)
+          sum += (weight * base.last)
+        end
+        base << (11 - (sum % 11)) % 10
+        base.join
+      end
+
       # Get a random French SIREN number. See more here https://fr.wikipedia.org/wiki/Syst%C3%A8me_d%27identification_du_r%C3%A9pertoire_des_entreprises
       def french_siren_number
         base = (1..8).map { rand(10) }.join

test/test_faker_company.rb

@@ -39,6 +39,13 @@ def test_swedish_organisation_number
     assert org_no[9] == @tester.send(:luhn_algorithm, org_no[0..8]).to_s
   end
 
+  def test_czech_organisation_number
+    org_no = @tester.czech_organisation_number
+    assert org_no.match(/\d{8}/)
+    assert [0, 1, 2, 3, 5, 6, 7, 8, 9].include?(org_no[0].to_i)
+    assert czech_o_n_checksum(org_no) == org_no[-1].to_i
+  end
+
   def test_french_siren_number
     siren = @tester.french_siren_number
     assert siren.match(/\A\d{9}\z/)
@@ -109,6 +116,16 @@ def test_mod11
 
   private
 
+  def czech_o_n_checksum(org_no)
+    weights = [8, 7, 6, 5, 4, 3, 2]
+    sum = 0
+    digits = org_no.split('').map(&:to_i)
+    weights.each_with_index.map do |w, i|
+      sum += (w * digits[i])
+    end
+    (11 - (sum % 11)) % 10
+  end
+
   def abn_checksum(abn)
     abn_weights = [10, 1, 3, 5, 7, 9, 11, 13, 15, 17, 19]