From 29fe84da85a9f5b706afb6322f2b434d0fc3c23f Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Tue, 20 Jan 2026 19:43:09 +0000
Subject: [PATCH 01/11] Bump @hotwired/turbo in the npm_and_yarn group across 1
 directory

Bumps the npm_and_yarn group with 1 update in the / directory: [@hotwired/turbo](https://github.com/hotwired/turbo).


Updates `@hotwired/turbo` from 8.0.2 to 8.0.21
- [Release notes](https://github.com/hotwired/turbo/releases)
- [Commits](https://github.com/hotwired/turbo/compare/v8.0.2...v8.0.21)

---
updated-dependencies:
- dependency-name: "@hotwired/turbo"
  dependency-version: 8.0.21
  dependency-type: indirect
  dependency-group: npm_and_yarn
...

Signed-off-by: dependabot[bot] <support@github.com>
---
 yarn.lock | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/yarn.lock b/yarn.lock
index 5937ba5..e8f2440 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -141,9 +141,9 @@
     "@rails/actioncable" "^7.0"
 
 "@hotwired/turbo@^8.0.2":
-  version "8.0.2"
-  resolved "https://registry.yarnpkg.com/@hotwired/turbo/-/turbo-8.0.2.tgz#c31cdadfe66b98983066a94073b26fc7e15835f0"
-  integrity sha512-3K6QZkwWfosAV8zuM5bY+kKF02jp1lMQGsWfSE6wXdZBRBP3ah+Vj26YNqYtkEomBwRWA0QKhZgyJP7xOQkVEg==
+  version "8.0.21"
+  resolved "https://registry.yarnpkg.com/@hotwired/turbo/-/turbo-8.0.21.tgz#a3e80c01d70048200f64bbe3582b84f9bfac034e"
+  integrity sha512-fJTv3JnzFHeDxBb23esZSOhT4r142xf5o3lKMFMvzPC6AllkqbBKk5Yb31UZhtIsKQCwmO/pUQrtTUlYl5CHAQ==
 
 "@nodelib/fs.scandir@2.1.5":
   version "2.1.5"

From 78c7428e6878f49a469f0714d2c722300db13e42 Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 14:50:46 -0500
Subject: [PATCH 02/11] Enhance ActiveAdmin Application index by batch-loading
 payment data and optimizing lodging cost retrieval to prevent N+1 queries

---
 app/admin/applications.rb | 29 ++++++++++++++++++++++-------
 1 file changed, 22 insertions(+), 7 deletions(-)

diff --git a/app/admin/applications.rb b/app/admin/applications.rb
index 3e43eb7..ee2c2bc 100644
--- a/app/admin/applications.rb
+++ b/app/admin/applications.rb
@@ -28,15 +28,30 @@
   filter :subscription, as: :select
   filter :conf_year, as: :select
 
+  controller do
+    def scoped_collection
+      end_of_association_chain.includes(:partner_registration)
+    end
+
+    def index
+      # Batch-load data to avoid N+1 in index columns
+      @payments_total_by_user_and_year = Payment
+        .where(transaction_status: '1')
+        .group(:user_id, :conf_year)
+        .sum(Arel.sql("total_amount::numeric"))
+      @lodgings_by_description = Lodging.all.index_by(&:description)
+      super
+    end
+  end
+
   index do
     selectable_column
     actions
     column :offer_status
     column "Balance Due" do |application|
-      users_current_payments = Payment.where(user_id: application.user_id, conf_year: application.conf_year)
-      ttl_paid = Payment.where(user_id: application.user_id, conf_year: application.conf_year, transaction_status: '1').pluck(:total_amount).map(&:to_f).sum / 100
-      cost_lodging = Lodging.find_by(description: application.lodging_selection).cost.to_f
-      cost_partner = application.partner_registration.cost.to_f
+      ttl_paid = (@payments_total_by_user_and_year[[application.user_id, application.conf_year]] || 0).to_f / 100
+      cost_lodging = (@lodgings_by_description[application.lodging_selection]&.cost || 0).to_f
+      cost_partner = application.partner_registration&.cost.to_f
       total_cost = cost_lodging + cost_partner
       balance_due = total_cost - ttl_paid
       number_to_currency(balance_due)
@@ -49,7 +64,7 @@
     column :workshop_selection3
     column :lodging_selection
     column "partner_registration_id" do |application|
-      application.partner_registration.display_name
+      application.partner_registration&.display_name
     end
     column :birth_year
   end
@@ -66,14 +81,14 @@
       table_for application.user.payments.where(conf_year: application.conf_year) do #application.user.payments.current_conference_payments
         column(:id) { |aid| link_to(aid.id, admin_payment_path(aid.id)) }
         column(:account_type) { |atype| atype.account_type.titleize }
-        column(:transaction_type) 
+        column(:transaction_type)
         column(:transaction_date) {|td| Date.parse(td.transaction_date) }
         column(:total_amount) { |ta|  number_to_currency(ta.total_amount.to_f / 100) }
       end
       text_node link_to("[Add Manual Payment]", new_admin_payment_path(:user_id => application))
     end
 
-    
+
     attributes_table do
       row :user
       row :conf_year

From 9e335ece7fc5cd1bcc1fd11cad949d5279438814 Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 14:51:34 -0500
Subject: [PATCH 03/11] Remove redundant payment queries in ActiveAdmin
 Application show view for improved performance

---
 app/admin/applications.rb | 2 --
 1 file changed, 2 deletions(-)

diff --git a/app/admin/applications.rb b/app/admin/applications.rb
index ee2c2bc..76d2ca2 100644
--- a/app/admin/applications.rb
+++ b/app/admin/applications.rb
@@ -71,7 +71,6 @@ def index
 
   show do
 
-    users_current_payments = Payment.where(user_id: application.user_id, conf_year: application.conf_year) # Payment.current_conference_payments.where(user_id: application.user_id)
     ttl_paid = Payment.where(user_id: application.user_id, conf_year: application.conf_year, transaction_status: '1').pluck(:total_amount).map(&:to_f).sum / 100
     cost_lodging = Lodging.find_by(description: application.lodging_selection).cost.to_f
     cost_partner = application.partner_registration.cost.to_f
@@ -176,7 +175,6 @@ def index
     column :lottery_position
     column :offer_status
     column "Balance Due" do |application|
-      users_current_payments = Payment.current_conference_payments.where(user_id: application.user_id)
       ttl_paid = Payment.current_conference_payments.where(user_id: application.user_id, transaction_status: '1').pluck(:total_amount).map(&:to_f).sum / 100
       cost_lodging = Lodging.find_by(description: application.lodging_selection).cost.to_f
       cost_partner = application.partner_registration.cost.to_f

From ab3b767db4e6fce05abffdedebc821f3a64d8bb0 Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 15:03:59 -0500
Subject: [PATCH 04/11] Skip application mock for admin applications index in
 request specs to ensure real ActiveRecord chain is used

---
 spec/requests/admin_applications_spec.rb | 38 ++++++++++++++++++++++++
 spec/support/application_mock.rb         |  3 ++
 2 files changed, 41 insertions(+)
 create mode 100644 spec/requests/admin_applications_spec.rb

diff --git a/spec/requests/admin_applications_spec.rb b/spec/requests/admin_applications_spec.rb
new file mode 100644
index 0000000..23aee5d
--- /dev/null
+++ b/spec/requests/admin_applications_spec.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe 'Admin Applications index', type: :request, no_application_mock: true do
+  let(:admin_user) { create(:admin_user) }
+
+  describe 'GET /admin/applications' do
+    context 'when admin is not signed in' do
+      it 'redirects to admin sign in page' do
+        get admin_applications_path
+        expect(response).to redirect_to(new_admin_user_session_path)
+      end
+    end
+
+    context 'when admin is signed in' do
+      before { sign_in admin_user }
+
+      it 'renders successfully with default scope' do
+        get admin_applications_path
+        expect(response).to be_successful
+      end
+
+      it 'renders successfully with scope=all (batch data loaded)' do
+        get admin_applications_path, params: { scope: 'all' }
+        expect(response).to be_successful
+      end
+
+      it 'includes Balance Due column when applications exist' do
+        create(:lodging, description: 'Standard')
+        create(:application, lodging_selection: 'Standard')
+        get admin_applications_path
+        expect(response).to be_successful
+        expect(response.body).to include('Balance Due')
+      end
+    end
+  end
+end
diff --git a/spec/support/application_mock.rb b/spec/support/application_mock.rb
index ed7936b..fcd2fec 100644
--- a/spec/support/application_mock.rb
+++ b/spec/support/application_mock.rb
@@ -1,5 +1,8 @@
 RSpec.configure do |config|
   config.before(:each, type: :request) do
+    # Skip mock when testing admin applications index (needs real ActiveRecord chain)
+    next if RSpec.current_example.metadata[:no_application_mock]
+
     # Create a mock for Application.active_conference_applications
     mock_active_applications = double("ActiveApplications")
 

From 1e15adff40993908b076a3c26695259e9c8e6eea Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 15:04:06 -0500
Subject: [PATCH 05/11] Optimize ActiveAdmin Application index by implementing
 a before_action to batch-load payment data, enhancing performance and
 preventing N+1 queries in the index view.

---
 app/admin/applications.rb | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/app/admin/applications.rb b/app/admin/applications.rb
index 76d2ca2..87d33a7 100644
--- a/app/admin/applications.rb
+++ b/app/admin/applications.rb
@@ -29,18 +29,24 @@
   filter :conf_year, as: :select
 
   controller do
+    before_action :load_index_batch_data, only: [:index]
+
     def scoped_collection
       end_of_association_chain.includes(:partner_registration)
     end
 
     def index
-      # Batch-load data to avoid N+1 in index columns
+      super
+    end
+
+    private
+
+    def load_index_batch_data
       @payments_total_by_user_and_year = Payment
         .where(transaction_status: '1')
         .group(:user_id, :conf_year)
         .sum(Arel.sql("total_amount::numeric"))
       @lodgings_by_description = Lodging.all.index_by(&:description)
-      super
     end
   end
 
@@ -49,8 +55,10 @@ def index
     actions
     column :offer_status
     column "Balance Due" do |application|
-      ttl_paid = (@payments_total_by_user_and_year[[application.user_id, application.conf_year]] || 0).to_f / 100
-      cost_lodging = (@lodgings_by_description[application.lodging_selection]&.cost || 0).to_f
+      payments_totals = @payments_total_by_user_and_year || {}
+      lodgings_by_desc = @lodgings_by_description || {}
+      ttl_paid = (payments_totals[[application.user_id, application.conf_year]] || 0).to_f / 100
+      cost_lodging = (lodgings_by_desc[application.lodging_selection]&.cost || 0).to_f
       cost_partner = application.partner_registration&.cost.to_f
       total_cost = cost_lodging + cost_partner
       balance_due = total_cost - ttl_paid

From c7a925bc832c92c0f64f45c9d1df34ec437cf176 Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 15:18:46 -0500
Subject: [PATCH 06/11] Refactor ActiveAdmin Dashboard to optimize applicant
 balance calculations by batch-loading payment data and lodging descriptions,
 improving performance and reducing query overhead.

---
 app/admin/dashboard.rb | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/app/admin/dashboard.rb b/app/admin/dashboard.rb
index 9826543..f736280 100644
--- a/app/admin/dashboard.rb
+++ b/app/admin/dashboard.rb
@@ -45,10 +45,14 @@
       end
       column do
         panel "#{ApplicationSetting.get_current_app_year} Applicants who accepted their offer (#{Application.application_accepted.count})" do
-          table_for Application.application_accepted.sort.reverse do
+          applications = Application.application_accepted.includes(:partner_registration).sort.reverse
+          raw_payments = Payment.where(transaction_status: '1').group(:user_id, :conf_year).sum(Arel.sql("total_amount::numeric"))
+          payments_totals = raw_payments.transform_keys { |k| [k[0].to_i, k[1].to_i] }
+          lodgings_by_desc = Lodging.all.index_by(&:description)
+          table_for applications do
             column("Applicant") { |u| link_to(u.display_name, admin_application_path(u.id)) }
             column("Offer Date") { |od| od.offer_status_date }
-            column("Balance Due") { |a| number_to_currency a.balance_due }
+            column("Balance Due") { |a| number_to_currency(a.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc)) }
           end
         end
       end

From 39fbbe6438bdbbae52d0e357899e6ba027b0a765 Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 15:19:04 -0500
Subject: [PATCH 07/11] Implement balance_due_with_batch method in Application
 model for optimized balance calculations, and update ActiveAdmin to utilize
 this method, enhancing performance and reducing query complexity.

---
 app/admin/applications.rb       | 11 ++++-------
 app/models/application.rb       | 14 +++++++++++++-
 spec/models/application_spec.rb | 34 +++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+), 8 deletions(-)

diff --git a/app/admin/applications.rb b/app/admin/applications.rb
index 87d33a7..298b19b 100644
--- a/app/admin/applications.rb
+++ b/app/admin/applications.rb
@@ -42,10 +42,12 @@ def index
     private
 
     def load_index_batch_data
-      @payments_total_by_user_and_year = Payment
+      raw = Payment
         .where(transaction_status: '1')
         .group(:user_id, :conf_year)
         .sum(Arel.sql("total_amount::numeric"))
+      # Normalize keys to [Integer, Integer] so lookup matches regardless of DB return type
+      @payments_total_by_user_and_year = raw.transform_keys { |k| [k[0].to_i, k[1].to_i] }
       @lodgings_by_description = Lodging.all.index_by(&:description)
     end
   end
@@ -57,12 +59,7 @@ def load_index_batch_data
     column "Balance Due" do |application|
       payments_totals = @payments_total_by_user_and_year || {}
       lodgings_by_desc = @lodgings_by_description || {}
-      ttl_paid = (payments_totals[[application.user_id, application.conf_year]] || 0).to_f / 100
-      cost_lodging = (lodgings_by_desc[application.lodging_selection]&.cost || 0).to_f
-      cost_partner = application.partner_registration&.cost.to_f
-      total_cost = cost_lodging + cost_partner
-      balance_due = total_cost - ttl_paid
-      number_to_currency(balance_due)
+      number_to_currency(application.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc))
     end
     column :first_name
     column :last_name
diff --git a/app/models/application.rb b/app/models/application.rb
index 5b15d72..11f0124 100644
--- a/app/models/application.rb
+++ b/app/models/application.rb
@@ -87,7 +87,7 @@ def total_user_has_paid
   end
 
   def lodging_cost
-    Lodging.find_by(description: self.lodging_selection).cost.to_f 
+    Lodging.find_by(description: self.lodging_selection).cost.to_f
   end
 
   def partner_registration_cost
@@ -102,6 +102,18 @@ def balance_due
     total_cost - total_user_has_paid
   end
 
+  # Balance due in dollars using preloaded data (avoids N+1). Payments total is in cents.
+  # Returns a rounded float suitable for number_to_currency.
+  def balance_due_with_batch(payments_totals:, lodgings_by_desc:)
+    key = [user_id.to_i, conf_year.to_i]
+    ttl_paid_cents = (payments_totals[key] || 0).to_f
+    ttl_paid_dollars = ttl_paid_cents / 100
+    cost_lodging = (lodgings_by_desc[lodging_selection]&.cost || 0).to_f
+    cost_partner = (partner_registration&.cost || 0).to_f
+    total_cost = cost_lodging + cost_partner
+    (total_cost - ttl_paid_dollars).round(2)
+  end
+
   def first_workshop_instructor
     Workshop.find(workshop_selection1).instructor
   end
diff --git a/spec/models/application_spec.rb b/spec/models/application_spec.rb
index 84fed9f..81d5bdd 100644
--- a/spec/models/application_spec.rb
+++ b/spec/models/application_spec.rb
@@ -191,6 +191,40 @@
       end
     end
 
+    describe '#balance_due_with_batch' do
+      it 'returns balance as total cost minus paid (payments in cents), rounded to 2 decimals' do
+        app = build(:application, user_id: 100, conf_year: 2026, lodging_selection: 'Standard')
+        allow(app).to receive(:partner_registration).and_return(double('PartnerRegistration', cost: 50.0))
+        payments_totals = { [100, 2026] => 10_000 }  # $100 in cents
+        lodgings_by_desc = { 'Standard' => double('Lodging', cost: 100.0) }
+        expect(app.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc)).to eq(50.0)
+      end
+
+      it 'uses 0 for paid when key is missing in payments_totals' do
+        app = build(:application, user_id: 100, conf_year: 2026, lodging_selection: 'Standard')
+        allow(app).to receive(:partner_registration).and_return(double('PartnerRegistration', cost: 50.0))
+        payments_totals = {}
+        lodgings_by_desc = { 'Standard' => double('Lodging', cost: 100.0) }
+        expect(app.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc)).to eq(150.0)
+      end
+
+      it 'returns negative balance when paid exceeds total cost (overpayment)' do
+        app = build(:application, user_id: 100, conf_year: 2026, lodging_selection: 'Standard')
+        allow(app).to receive(:partner_registration).and_return(double('PartnerRegistration', cost: 50.0))
+        payments_totals = { [100, 2026] => 20_000 }  # $200 in cents
+        lodgings_by_desc = { 'Standard' => double('Lodging', cost: 100.0) }
+        expect(app.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc)).to eq(-50.0)
+      end
+
+      it 'uses 0 for missing lodging or partner and rounds to 2 decimals' do
+        app = build(:application, user_id: 100, conf_year: 2026, lodging_selection: 'Unknown')
+        allow(app).to receive(:partner_registration).and_return(nil)
+        payments_totals = { [100, 2026] => 0 }
+        lodgings_by_desc = {}
+        expect(app.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc)).to eq(0.0)
+      end
+    end
+
     describe '#first_workshop_instructor' do
       it 'returns the instructor of the first workshop' do
         workshop = double("Workshop", instructor: "John Smith")

From 1b0e5adffc5c14dfe25d1b6b20bb913d40ef64f0 Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 15:31:52 -0500
Subject: [PATCH 08/11] Refactor ActiveAdmin Application balance calculation to
 use controller instance variables for improved clarity and maintainability.

---
 app/admin/applications.rb | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/app/admin/applications.rb b/app/admin/applications.rb
index 298b19b..ec9ef47 100644
--- a/app/admin/applications.rb
+++ b/app/admin/applications.rb
@@ -57,8 +57,8 @@ def load_index_batch_data
     actions
     column :offer_status
     column "Balance Due" do |application|
-      payments_totals = @payments_total_by_user_and_year || {}
-      lodgings_by_desc = @lodgings_by_description || {}
+      payments_totals = controller.instance_variable_get(:@payments_total_by_user_and_year) || {}
+      lodgings_by_desc = controller.instance_variable_get(:@lodgings_by_description) || {}
       number_to_currency(application.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc))
     end
     column :first_name

From c02285dd31a81d73a7f82d657e87a685b8b6a1e8 Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 15:51:09 -0500
Subject: [PATCH 09/11] Enhance error handling in Application model and
 ActiveAdmin for missing partner_registration, ensuring data integrity and
 preventing incorrect balance calculations.

---
 app/admin/applications.rb       | 10 ++++++++--
 app/models/application.rb       |  4 +++-
 spec/models/application_spec.rb |  5 +++--
 3 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/app/admin/applications.rb b/app/admin/applications.rb
index ec9ef47..9fd62a0 100644
--- a/app/admin/applications.rb
+++ b/app/admin/applications.rb
@@ -78,6 +78,9 @@ def load_index_batch_data
 
     ttl_paid = Payment.where(user_id: application.user_id, conf_year: application.conf_year, transaction_status: '1').pluck(:total_amount).map(&:to_f).sum / 100
     cost_lodging = Lodging.find_by(description: application.lodging_selection).cost.to_f
+    if application.partner_registration.nil?
+      raise "Partner registration is missing for this application (id=#{application.id}); cannot compute balance. Fix data and retry."
+    end
     cost_partner = application.partner_registration.cost.to_f
     total_cost = cost_lodging + cost_partner
     balance_due = total_cost - ttl_paid
@@ -119,7 +122,7 @@ def load_index_batch_data
       row :workshop_selection3
       row :lodging_selection
       row "partner_registration_id" do |app|
-        app.partner_registration.display_name
+        app.partner_registration&.display_name
       end
       row :partner_first_name
       row :partner_last_name
@@ -180,6 +183,9 @@ def load_index_batch_data
     column :lottery_position
     column :offer_status
     column "Balance Due" do |application|
+      if application.partner_registration.nil?
+        raise "Application #{application.id}: partner_registration is missing; cannot compute balance for CSV export."
+      end
       ttl_paid = Payment.current_conference_payments.where(user_id: application.user_id, transaction_status: '1').pluck(:total_amount).map(&:to_f).sum / 100
       cost_lodging = Lodging.find_by(description: application.lodging_selection).cost.to_f
       cost_partner = application.partner_registration.cost.to_f
@@ -196,7 +202,7 @@ def load_index_batch_data
     column :workshop_selection3
     column :lodging_selection
     column "partner_registration_id" do |app|
-      app.partner_registration.display_name
+      app.partner_registration&.display_name
     end
     column :birth_year
     column :street
diff --git a/app/models/application.rb b/app/models/application.rb
index 11f0124..8ac5f9d 100644
--- a/app/models/application.rb
+++ b/app/models/application.rb
@@ -104,12 +104,14 @@ def balance_due
 
   # Balance due in dollars using preloaded data (avoids N+1). Payments total is in cents.
   # Returns a rounded float suitable for number_to_currency.
+  # Raises if partner_registration is missing (data integrity: do not treat missing as $0).
   def balance_due_with_batch(payments_totals:, lodgings_by_desc:)
+    raise "Application #{id}: partner_registration is missing; cannot compute balance." if partner_registration.nil?
     key = [user_id.to_i, conf_year.to_i]
     ttl_paid_cents = (payments_totals[key] || 0).to_f
     ttl_paid_dollars = ttl_paid_cents / 100
     cost_lodging = (lodgings_by_desc[lodging_selection]&.cost || 0).to_f
-    cost_partner = (partner_registration&.cost || 0).to_f
+    cost_partner = partner_registration.cost.to_f
     total_cost = cost_lodging + cost_partner
     (total_cost - ttl_paid_dollars).round(2)
   end
diff --git a/spec/models/application_spec.rb b/spec/models/application_spec.rb
index 81d5bdd..1e3ec49 100644
--- a/spec/models/application_spec.rb
+++ b/spec/models/application_spec.rb
@@ -216,12 +216,13 @@
         expect(app.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc)).to eq(-50.0)
       end
 
-      it 'uses 0 for missing lodging or partner and rounds to 2 decimals' do
+      it 'raises when partner_registration is missing (do not treat as $0)' do
         app = build(:application, user_id: 100, conf_year: 2026, lodging_selection: 'Unknown')
         allow(app).to receive(:partner_registration).and_return(nil)
         payments_totals = { [100, 2026] => 0 }
         lodgings_by_desc = {}
-        expect(app.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc)).to eq(0.0)
+        expect { app.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc) }
+          .to raise_error(/partner_registration is missing/)
       end
     end
 

From 082ebc756aa278c4fba1ac9bbf1eabc786cb0cba Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 15:55:15 -0500
Subject: [PATCH 10/11] Remove unused index method from ActiveAdmin
 Application, streamlining the controller and improving code clarity.

---
 app/admin/applications.rb | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/app/admin/applications.rb b/app/admin/applications.rb
index 9fd62a0..3bc5eff 100644
--- a/app/admin/applications.rb
+++ b/app/admin/applications.rb
@@ -35,10 +35,6 @@ def scoped_collection
       end_of_association_chain.includes(:partner_registration)
     end
 
-    def index
-      super
-    end
-
     private
 
     def load_index_batch_data

From b6cc89c4fc009ce6860f2116da8705bd70b7b741 Mon Sep 17 00:00:00 2001
From: rsmokeUM <rsmoke@umich.edu>
Date: Tue, 3 Feb 2026 16:13:44 -0500
Subject: [PATCH 11/11] Enhance balance_due_with_batch method in Application
 model to raise errors for missing lodging selections, improving data
 integrity and error handling in balance calculations.

---
 app/models/application.rb       | 6 ++++--
 spec/models/application_spec.rb | 9 +++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/app/models/application.rb b/app/models/application.rb
index 8ac5f9d..49e40f5 100644
--- a/app/models/application.rb
+++ b/app/models/application.rb
@@ -104,13 +104,15 @@ def balance_due
 
   # Balance due in dollars using preloaded data (avoids N+1). Payments total is in cents.
   # Returns a rounded float suitable for number_to_currency.
-  # Raises if partner_registration is missing (data integrity: do not treat missing as $0).
+  # Raises if partner_registration or lodging is missing (data integrity: do not treat missing as $0).
   def balance_due_with_batch(payments_totals:, lodgings_by_desc:)
     raise "Application #{id}: partner_registration is missing; cannot compute balance." if partner_registration.nil?
+    lodging = lodgings_by_desc[lodging_selection]
+    raise "Application #{id}: lodging not found for selection '#{lodging_selection}'; cannot compute balance." if lodging.nil?
     key = [user_id.to_i, conf_year.to_i]
     ttl_paid_cents = (payments_totals[key] || 0).to_f
     ttl_paid_dollars = ttl_paid_cents / 100
-    cost_lodging = (lodgings_by_desc[lodging_selection]&.cost || 0).to_f
+    cost_lodging = lodging.cost.to_f
     cost_partner = partner_registration.cost.to_f
     total_cost = cost_lodging + cost_partner
     (total_cost - ttl_paid_dollars).round(2)
diff --git a/spec/models/application_spec.rb b/spec/models/application_spec.rb
index 1e3ec49..c1aa56b 100644
--- a/spec/models/application_spec.rb
+++ b/spec/models/application_spec.rb
@@ -224,6 +224,15 @@
         expect { app.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc) }
           .to raise_error(/partner_registration is missing/)
       end
+
+      it 'raises when lodging is not found in lodgings_by_desc (do not treat as $0)' do
+        app = build(:application, user_id: 100, conf_year: 2026, lodging_selection: 'DeletedOrInvalidLodging')
+        allow(app).to receive(:partner_registration).and_return(double('PartnerRegistration', cost: 50.0))
+        payments_totals = { [100, 2026] => 0 }
+        lodgings_by_desc = { 'Standard' => double('Lodging', cost: 100.0) }
+        expect { app.balance_due_with_batch(payments_totals: payments_totals, lodgings_by_desc: lodgings_by_desc) }
+          .to raise_error(/lodging not found for selection 'DeletedOrInvalidLodging'/)
+      end
     end
 
     describe '#first_workshop_instructor' do