CLDC-3938 set ppostcode on postcode change to fix bu bug (#2994)

* set renewal ppostcode on postcode change

* update test

* don't validate ppostcode format if nil

* reset ppcodenk if ppcode errors

---------

Co-authored-by: Carolyn <carolyn.barker@softwire.com>

app/models/lettings_log.rb

@@ -649,6 +649,7 @@ class LettingsLog < Log
     super
 
     self.postcode_known = nil if errors.attribute_names.include? :postcode_full
+    self.ppcodenk = nil if errors.attribute_names.include? :ppostcode_full
 
     if errors.of_kind?(:earnings, :under_hard_min)
       self.incfreq = nil
@@ -714,9 +715,17 @@ class LettingsLog < Log
 
   def process_postcode_changes!
     self.postcode_full = upcase_and_remove_whitespace(postcode_full)
+
+    if is_renewal?
+      self.ppostcode_full = upcase_and_remove_whitespace(postcode_full)
+    end
+
     return if postcode_full.blank?
 
     self.postcode_known = 1
+    if is_renewal?
+      self.ppcodenk = 0
+    end
     inferred_la = get_inferred_la(postcode_full)
     self.is_la_inferred = inferred_la.present?
     self.la = inferred_la if inferred_la.present?

app/models/validations/local_authority_validations.rb

@@ -1,6 +1,8 @@
 module Validations::LocalAuthorityValidations
   def validate_previous_accommodation_postcode(record)
     postcode = record.ppostcode_full
+    return unless postcode
+
     if record.previous_postcode_known? && (postcode.blank? || !postcode.match(POSTCODE_REGEXP))
       error_message = I18n.t("validations.postcode")
       record.errors.add :ppostcode_full, :wrong_format, message: error_message

spec/models/lettings_log_derived_fields_spec.rb

@@ -1016,11 +1016,13 @@ RSpec.describe LettingsLog, type: :model do
       postcode = "SW1A 1AA"
       log.assign_attributes(postcode_known: 1, postcode_full: postcode, renewal: 1)
 
-      expect { log.send :process_postcode_changes! }.to change(log, :la).to(expected_la)
+      expect { log.send :process_postcode_changes! }
-      expect { log.set_derived_fields! }
+        .to change(log, :la).to(expected_la)
-        .to change(log, :ppostcode_full).to(postcode)
+        .and change(log, :ppostcode_full).to(postcode)
         .and change(log, :ppcodenk).to(0)
-        .and change(log, :prevloc).to(expected_la)
+
+      expect { log.set_derived_fields! }
+        .to change(log, :prevloc).to(expected_la)
     end
 
     it "clears values for previous location and related fields when log is a renewal and current values are cleared" do