infer day, month, year instead

app/models/case_log.rb

@@ -183,8 +183,10 @@ private
       self.mrcmonth = mrcdate.month
       self.mrcyear = mrcdate.year
     end
-    if day.present? && month.present? && year.present?
-      self.startdate = Time.zone.local(year, month, day)
+    if startdate.present?
+      self.day = startdate.day
+      self.month = startdate.month
+      self.year = startdate.year
     end
     self.incref = 1 if net_income_known == "Prefer not to say"
     self.hhmemb = other_hhmemb + 1 if other_hhmemb.present?

spec/models/case_log_spec.rb

@@ -881,10 +881,8 @@ RSpec.describe Form, type: :model do
         owning_organisation: organisation,
         property_postcode: "M1 1AE",
         previous_postcode: "M2 2AE",
-        day: 10,
-        month: 10,
-        year: 2021,
         # rubocop:disable Style/DateTime
+        startdate: DateTime.new(2021, 10, 10),
         mrcdate: DateTime.new(2021, 5, 4),
         # rubocop:enable Style/DateTime
         net_income_known: "Prefer not to say",
@@ -952,12 +950,16 @@ RSpec.describe Form, type: :model do
       expect(record_from_db["lettype"]).to eq(9)
     end
 
-    it "correctly derives and saves startdate" do
+    it "correctly derives and saves day, month, year from start date" do
       case_log.reload
 
-      record_from_db = ActiveRecord::Base.connection.execute("select startdate from case_logs where id=#{case_log.id}").to_a[0]
-      expect(case_log.startdate).to eq(Time.zone.local(2021, 10, 10))
-      expect(record_from_db["startdate"]).to eq(Time.zone.local(2021, 10, 10))
+      record_from_db = ActiveRecord::Base.connection.execute("select day, month, year, startdate from case_logs where id=#{case_log.id}").to_a[0]
+      expect(record_from_db["startdate"].day).to eq(10)
+      expect(record_from_db["startdate"].month).to eq(10)
+      expect(record_from_db["startdate"].year).to eq(2021)
+      expect(record_from_db["day"]).to eq(10)
+      expect(record_from_db["month"]).to eq(10)
+      expect(record_from_db["year"]).to eq(2021)
     end
   end
 end