AP-3563: Fix error message and form value rendering

This fixes an underlying bug that causes the behaviour described
in the bug ticket AP-3563. Namely, that while the amount for any
cash income or outgoing type is validated it is not done in the way
common to other pages or forms. This has resulted in a difference
whereby comma separated monetayr values, `1,000`, are invalid but
where being rendered as a value when the form errors and rerenders.

This has been corrected to emulate the functionality seen in
form objects with monetary amount fields.

1. It now "cleans" the monetary amount params to remove `£` and `,`.

2. When rendering the form the field value is no longer rendered as a
"number to currency" value with no unit - which was rendering commas
for numeric values over 3 digits long.

app/models/base_aggregated_cash_transaction.rb

@@ -88,11 +88,22 @@ def transaction_date(month_number)
   end
 
   def update_cash_attributes(params)
-    params.each do |key, value|
+    cleaned_params = clean_attributes(params)
+    cleaned_params.each do |key, value|
       __send__(:"#{key}=", value)
     end
   end
 
+  def clean_attributes(params)
+    params.each.with_object({}) do |(k, v), new_hash|
+      new_hash[k] = cash_transaction_amount_field?(k) ? v.to_s.tr("£,", "") : v
+    end
+  end
+
+  def cash_transaction_amount_field?(param_name)
+    self.class.cash_transaction_categories.map(&:to_s).any? { |category| param_name.start_with?(category) }
+  end
+
   def save_cash_transaction_records
     self.class.cash_transaction_categories.each do |category|
       CashTransaction.where(

app/views/shared/partials/_revealing_checkbox.html.erb

@@ -13,7 +13,7 @@
     <% end %>
     <%= form.govuk_text_field "#{name}#{number}",
                               label: { text: model.period(number) },
-                              value: gds_number_to_currency(model.__send__(:"#{name}#{number}"), unit: ""),
+                              value: model.__send__(:"#{name}#{number}"),
                               prefix_text: defined?(input_prefix) ? input_prefix : nil,
                               form_group: { classes: error_class },
                               width: "one-third" %>

spec/models/aggregated_cash_income_spec.rb

@@ -300,6 +300,15 @@
         end
       end
 
+      context "with valid comma separate monetary params" do
+        let(:params) { valid_params.merge(benefits1: "1,222,222.33") }
+
+        it "creates the expected cash income records" do
+          expect { call_update }.to change(CashTransaction, :count).by(6)
+          expect(CashTransaction.pluck(:amount)).to include(1_222_222.33)
+        end
+      end
+
       context "with invalid params" do
         context "and non-numeric values" do
           let(:params) { non_numeric_params }

spec/models/aggregated_cash_outgoings_spec.rb

@@ -250,6 +250,15 @@ def error_msg(name, month)
         end
       end
 
+      context "with valid comma separate monetary params" do
+        let(:params) { valid_params.merge(rent_or_mortgage1: "1,222,222.33") }
+
+        it "creates the expected cash income records" do
+          expect { call_update }.to change(CashTransaction, :count).by(6)
+          expect(CashTransaction.pluck(:amount)).to include(1_222_222.33)
+        end
+      end
+
       context "with invalid params" do
         context "and non-numeric values" do
           let(:params) { non_numeric_params }