Link to zendesk tickets from edition notes automatically

app/helpers/action_helper.rb

@@ -11,14 +11,24 @@ def action_note(action)
     if action.comment.present?
       format_and_auto_link_plain_text(action.comment)
     elsif action.is_fact_check_request? && action.email_addresses.present?
-      "Request sent to #{mail_to action.email_addresses}"
+      "Request sent to #{mail_to action.email_addresses}".html_safe
     elsif action.recipient_id.present?
-      "Assigned to #{mail_to action.recipient.email, action.recipient.name}"
+      "Assigned to #{mail_to action.recipient.email, action.recipient.name}".html_safe
     end
   end
 
   def format_and_auto_link_plain_text(text)
     text = auto_link(escape_once(text), link: :urls, sanitize: false)
-    simple_format(text, {}, :sanitize => false)
+    text = auto_link_zendesk_tickets(text)
+    simple_format(text, {}, :sanitize => false).html_safe
+  end
+
+  def auto_link_zendesk_tickets(text)
+    text = text.gsub(/(?:zen|zendesk|zendesk ticket)(?:\s)?(?:#|\:)?(?:\s)?(\d{4,})/i) do |match|
+      ticket = $1
+      link_to match, "https://govuk.zendesk.com/tickets/#{ticket}"
+    end
+
+    text.html_safe
   end
 end

app/views/shared/_edition_history.html.erb

@@ -34,7 +34,7 @@
                 </div>
               <% end %>
               <blockquote class="add-left-margin">
-                <%= action_note(action).html_safe %>
+                <%= action_note(action) %>
               </blockquote>
             <% end %>
           </li>

test/unit/helpers/admin/action_helper_test.rb

@@ -0,0 +1,17 @@
+require 'test_helper'
+
+class ActionHelperTest < ActionView::TestCase
+  test "it converts zendesk tickets to links" do
+
+    expected_link = 'https://govuk.zendesk.com/tickets/1234'
+    texts = ['Zendesk ticket #1234', 'zendesk 1234', 'Zen 1234', 'zen #1234', 'zen#1234', 'zen:1234', 'zendesk: 1234']
+
+    texts.each do |text|
+      assert_equal auto_link_zendesk_tickets(text), "<a href=\"#{expected_link}\">#{text}</a>"
+    end
+
+    assert_equal auto_link_zendesk_tickets("zendesk 1234. Next"), "<a href=\"#{expected_link}\">zendesk 1234</a>. Next"
+    assert_equal auto_link_zendesk_tickets("something something zendesk 1234. Next"), "something something <a href=\"#{expected_link}\">zendesk 1234</a>. Next"
+    assert_equal auto_link_zendesk_tickets("somezendesk 1234. Next"), "some<a href=\"#{expected_link}\">zendesk 1234</a>. Next"
+  end
+end