Fix bug when in specific scenario user couldn't proceed to payment step

When using a "pick up" shipping method, with a user who doesn't have a shipping address it was impossible to proceed to the payment step because shipping address was invalid.

To fix this, we ensure that "ship_address_same_as_billing" parameter is set to true when using a "pick up" shipping method.

use distributor address when shipping method doesn't require a ship address ; in doing this we follow the same logic as the legacy checkout

app/controllers/split_checkout_controller.rb

@@ -141,6 +141,10 @@ class SplitCheckoutController < ::BaseController
   def update_order
     return if params[:confirm_order] || @order.errors.any?
 
+    # If we have "pick up" shipping method (require_ship_address is set to false), use the
+    # distributor address as shipping address
+    use_shipping_address_from_distributor if shipping_method_ship_address_not_required?
+
     @order.select_shipping_method(params[:shipping_method_id])
     @order.update(order_params)
     @order.updater.update_totals_and_states
@@ -150,6 +154,29 @@ class SplitCheckoutController < ::BaseController
     @order.errors.empty?
   end
 
+  def use_shipping_address_from_distributor
+    @order.ship_address = @order.address_from_distributor
+
+    # Add the missing data
+    bill_address = params[:order][:bill_address_attributes]
+    @order.ship_address.firstname = bill_address[:firstname]
+    @order.ship_address.lastname = bill_address[:lastname]
+    @order.ship_address.phone = bill_address[:phone]
+
+    # Remove shipping address from parameter so we don't override the address we just set
+    params[:order].delete(:ship_address_attributes)
+  end
+
+  def shipping_method_ship_address_not_required?
+    selected_shipping_method = allowed_shipping_methods&.select do |sm|
+      sm.id.to_s == params[:shipping_method_id]
+    end
+
+    return false if selected_shipping_method.empty?
+
+    selected_shipping_method.first.require_ship_address == false
+  end
+
   def summary_step?
     params[:step] == "summary"
   end

spec/system/consumer/split_checkout_spec.rb

@@ -458,6 +458,19 @@ describe "As a consumer, I want to checkout my order" do
             fill_notes("SpEcIaL NoTeS")
             proceed_to_payment
           end
+
+          context 'when the user has no shipping address' do
+            before do
+              # Hack so we can have "Shipping address same as billing address?" unticked
+              choose free_shipping_with_required_address.name
+              uncheck "Shipping address same as billing address?"
+              choose free_shipping_without_required_address.name
+            end
+
+            it "redirects the user to the Payment Method step" do
+              proceed_to_payment
+            end
+          end
         end
 
         describe "selecting a delivery method with a shipping fee" do