Add registrar IBAN

test/fixtures/registrars.yml

@@ -11,6 +11,7 @@ bestnames:
   billing_email: billing@bestnames.test
   website:  https://bestnames.test
   reference_no: 13
+  iban: GB33BUKB20201555555555
 
 goodnames:
   name: Good Names

test/integration/admin_area/registrars_test.rb

@@ -0,0 +1,20 @@
+require 'test_helper'
+
+class AdminAreaRegistrarsIntegrationTest < ActionDispatch::IntegrationTest
+  include Devise::Test::IntegrationHelpers
+
+  setup do
+    @registrar = registrars(:bestnames)
+    sign_in users(:admin)
+  end
+
+  def test_updates_registrar_optional_attributes
+    new_iban = 'GB94BARC10201530093459'
+    assert_not_equal new_iban, @registrar.iban
+
+    patch admin_registrar_path(@registrar), registrar: { iban: new_iban }
+    @registrar.reload
+
+    assert_equal new_iban, @registrar.iban
+  end
+end