CLDC-4266: Reference UPRN in clear button for newbuilds

app/helpers/form_page_helper.rb

@@ -55,4 +55,12 @@ module FormPageHelper
       question.date_example_override(log) || "For example, #{date_mid_collection_year_formatted(log.startdate).tr(' ', '/')}",
     ].compact.join("<br><br>").html_safe
   end
+
+  def clear_address_text(log)
+    if log.lettings? && log.newbuild?
+      "Clear address and search by UPRN instead"
+    else
+      "Clear address and search instead"
+    end
+  end
 end

app/models/lettings_log.rb

@@ -815,12 +815,16 @@ class LettingsLog < Log
     "lettings_log"
   end
 
+  def newbuild?
+    rsnvac == 15
+  end
+
   def changed_to_newbuild?
-    rsnvac == 15 && rsnvac_was != 15
+    newbuild? && rsnvac_was != 15
   end
 
   def changed_from_newbuild?
-    rsnvac != 15 && rsnvac_was == 15
+    !newbuild? && rsnvac_was == 15
   end
 
   def is_address_asked?

app/views/form/guidance/_address_fallback.html.erb

@@ -1,3 +1,3 @@
 <div class="govuk-button-group">
-  <%= govuk_link_to "Clear address and search instead", address_search_input_path(@log.log_type, @log.id), class: "govuk-button govuk-button--secondary" %>
+  <%= govuk_link_to clear_address_text(@log), address_search_input_path(@log.log_type, @log.id), class: "govuk-button govuk-button--secondary" %>
 </div>