The enterprise fees are recreated and the shipping and payment fees are updated. The rest of the deleted code is not necessary (eg #with_open_adjustments). Everything else that needs to happen here is already done automatically (eg updating order totals).
Whatever fee adjustments there are on other line items should be left alone (not recreated), and whatever fee adjustments are already on the order should just be updated.
This method is named "update distribution charge". What this method actually does is delete all of the fee adjustments on an order and all it's line items, then recreate them all from scratch. We call this from lots of different places all the time, and it's incredibly expensive. It even gets called from inside of transactions being run inside callbacks. Renaming it hopefully will add a bit of clarity.
This needs to be a lot more granular!
Instead of relying on Spree::Order#outstanding_balance we make us of the
result set `balance_value` computed column. So, we ask PostgreSQL to
compute it instead of Ruby and then serialize it from that computed
column. That's a bit faster to compute that way and let's reuse logic.
We hide this new implementation under this features' toggle so it's only
used when enabled. We want hit the old behaviour by default.
This makes it possible to deploy it without releasing it to users since
the toggle is not enabled for anyone.
It aims to make the balance calculation consistent across pages.
This query object is meant to be reusable but those includes are
context-specific and will likely not be needed when reusing the query
elsewhere. If we keep them there, chances are next dev might not notice
it and will introduce a performance regression.
It's simpler and many orders of magnitude more efficient to ask the DB
to aggregate the customer balance based on their orders. It removes
a nasty N+1.
The resulting SQL query is:
```sql
SELECT customers.*, SUM(spree_orders.total - spree_orders.payment_total) AS balance
FROM "customers"
INNER JOIN "spree_orders"
ON "spree_orders"."customer_id" = "customers"."id"
WHERE "customers"."enterprise_id" = 1
AND (completed_at IS NOT NULL)
AND (state != 'canceled')
GROUP BY customers.id
ORDER BY email;
```
I'm not sure why this spec started failing. Fixes:
```
Spree::OrdersController viewing cart when an item is in the cart the page provides the right registration path
Failure/Error: expect(subject.registration_path).to eq registration_path
ActionController::UrlGenerationError:
No route matches {:action=>"index", :controller=>"registration"}
# ./spec/controllers/spree/orders_controller_spec.rb:140:in `block (5 levels) in <top (required)>'
```
