feat: add depends on behaviour

app/models/form/sales/pages/extra_borrowing.rb

@@ -4,6 +4,9 @@ class Form::Sales::Pages::ExtraBorrowing < ::Form::Page
     @header = ""
     @description = ""
     @subsection = subsection
+    @depends_on = [{
+                     "mortgageused" => 1,
+                   }]
   end
 
   def questions

spec/models/form/sales/pages/extra_borrowing_spec.rb

@@ -28,6 +28,8 @@ RSpec.describe Form::Sales::Pages::ExtraBorrowing, type: :model do
   end
 
   it "has correct depends_on" do
-    expect(page.depends_on).to be_nil
+    expect(page.depends_on).to eq([{
+      "mortgageused" => 1,
+    }])
   end
 end