Add Faker::NHS - Support for the British National Health Service (fak…

…er-ruby#801)

* Adds support for the British National Health Service fake data.

Every person in the United Kingdom has a unique code which identifies them to the National Health Service (NHS). The code is in XXX XXX XXXX format where the final digit is a check digit calculated from the previous ones.

More information on NHS numbers can be found here: https://en.wikipedia.org/wiki/NHS_number

This commit adds the Faker::NHS class along with the Faker::NHS.nhs_number method to generate a valid NHS number.

* Add docs

* Update changelog.md

* Naming fixes

CHANGELOG.md

@@ -6,6 +6,7 @@
 [Full Changelog](https://github.com/stympy/faker/compare/v1.8.7...v1.9.1)
 
 ### Feature Request
+- [PR #801](https://github.com/stympy/faker/pull/801) Add Faker::NHS - Support for the British National Health Service [@substrakt-health](https://github.com/substrakt-health)
 - [PR #1308](https://github.com/stympy/faker/pull/1308) Add Faker::BojackHorseman [@saurabhudaniya200](https://github.com/saurabhudaniya200)
 - [PR #1292](https://github.com/stympy/faker/pull/1292) Add Faker::Bank - account_number and routing_number [@vbrazo](https://github.com/vbrazo)
 - [PR #1300](https://github.com/stympy/faker/pull/1300) Add Faker::GreekPhilosophers [@15ngburton](https://github.com/15ngburton)

README.md

@@ -113,6 +113,7 @@ Contents
   - [Faker::Nation](doc/nation.md)
   - [Faker::NatoPhoneticAlphabet](doc/nato_phonetic_alphabet.md)
   - [Faker::NewGirl](doc/new_girl.md)
+  - [Faker::NationalHealthService](doc/national_health_service.md)
   - [Faker::Number](doc/number.md)
   - [Faker::Omniauth](doc/omniauth.md)
   - [Faker::OnePiece](doc/one_piece.md)

doc/national_health_service.md

@@ -0,0 +1,9 @@
+# Faker::NationalHealthService
+
+It might be available in the next version
+
+```ruby
+Faker::NationalHealthService.british_number #=> "403 958 5577"
+
+Faker::NationalHealthService.check_digit(400_012_114) #=> 6
+```

lib/faker/nhs.rb

@@ -0,0 +1,23 @@
+module Faker
+  class NationalHealthService < Base
+    class << self
+      def british_number
+        base_number = rand(400_000_000...499_999_999)
+        "#{base_number}#{check_digit(base_number)}".to_s
+                                                   .chars
+                                                   .insert(3, ' ')
+                                                   .insert(7, ' ')
+                                                   .join('')
+      end
+
+      def check_digit(number = 0)
+        sum = 0
+        number.to_s.chars.each_with_index do |digit, idx|
+          position = idx + 1
+          sum += (digit.to_i * (11 - position))
+        end
+        11 - (sum % 11)
+      end
+    end
+  end
+end

test/test_faker_national_health_service.rb

@@ -0,0 +1,15 @@
+require File.expand_path(File.dirname(__FILE__) + '/test_helper.rb')
+
+class TestFakerNationalHealthService < Test::Unit::TestCase
+  def setup
+    @tester = Faker::NationalHealthService
+  end
+
+  def test_nhs_british_number
+    assert_match(/\A\d{3}\s\d{3}\s\d{4}\z/, @tester.british_number)
+  end
+
+  def test_nhs_check_digit
+    assert_equal 6, @tester.check_digit(400_012_114)
+  end
+end