Refactor inactive contact archivation

Fixes #956

test/tasks/contacts/archive_test.rb

@@ -0,0 +1,46 @@
+require 'test_helper'
+
+class ArchiveContactsTaskTest < ActiveSupport::TestCase
+  def test_archives_inactive_contacts
+    eliminate_effect_of_all_contacts_except(archivable_contact)
+
+    assert_difference 'Contact.count', -1 do
+      capture_io { run_task }
+    end
+  end
+
+  def test_output
+    contact = archivable_contact
+    eliminate_effect_of_all_contacts_except(contact)
+
+    expected_output = "Contact ##{contact.id} (code: #{contact.code}) is archived\n" \
+                      "Archived total: 1\n"
+    assert_output(expected_output) { run_task }
+  end
+
+  private
+
+  def archivable_contact
+    contact = contacts(:john)
+    Contact.inactivity_period = 0.seconds
+    DomainVersion.delete_all
+
+    other_contact = contacts(:william)
+    assert_not_equal other_contact, contact
+    Domain.update_all(registrant_id: other_contact)
+
+    DomainContact.delete_all
+
+    contact
+  end
+
+  def eliminate_effect_of_all_contacts_except(contact)
+    Contact.connection.disable_referential_integrity do
+      Contact.delete_all("id != #{contact.id}")
+    end
+  end
+
+  def run_task
+    Rake::Task['contacts:archive'].execute
+  end
+end