From f35b70e9363bbf352445dbd40423b6301d989e49 Mon Sep 17 00:00:00 2001
From: Tony Vincent <tonyvince7@gmail.com>
Date: Mon, 17 Feb 2025 17:42:30 +0100
Subject: [PATCH] fix: Transfers should always total to zero (#1859)

---
 app/helpers/application_helper.rb               | 10 +++++++++-
 app/views/account/entries/_entry_group.html.erb |  4 +++-
 test/system/transactions_test.rb                | 16 ++++++++++++++--
 3 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 7549b6b5..424ed539 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -154,7 +154,7 @@ module ApplicationHelper
 
   def totals_by_currency(collection:, money_method:, separator: " | ", negate: false)
     collection.group_by(&:currency)
-              .transform_values { |item| negate ? item.sum(&money_method) * -1 : item.sum(&money_method) }
+              .transform_values { |item| calculate_total(item, money_method, negate) }
               .map { |_currency, money| format_money(money) }
               .join(separator)
   end
@@ -166,4 +166,12 @@ module ApplicationHelper
 
     cookies[:admin] == "true"
   end
+
+  private
+
+    def calculate_total(item, money_method, negate)
+      items = item.reject { |i| i.respond_to?(:entryable) && i.entryable.transfer? }
+      total = items.sum(&money_method)
+      negate ? -total : total
+    end
 end
diff --git a/app/views/account/entries/_entry_group.html.erb b/app/views/account/entries/_entry_group.html.erb
index 4006b070..beec5893 100644
--- a/app/views/account/entries/_entry_group.html.erb
+++ b/app/views/account/entries/_entry_group.html.erb
@@ -17,7 +17,9 @@
     </div>
 
     <% if totals %>
-      <%= totals_by_currency(collection: entries, money_method: :amount_money, negate: true) %>
+      <div id="entry-group-<%= date %>-totals">
+        <%= totals_by_currency(collection: entries, money_method: :amount_money, negate: true) %>
+      </div>
     <% end %>
   </div>
   <div class="bg-white shadow-xs rounded-md border border-alpha-black-25 divide-y divide-alpha-black-50">
diff --git a/test/system/transactions_test.rb b/test/system/transactions_test.rb
index 3fc0b5e1..3c9dd3fd 100644
--- a/test/system/transactions_test.rb
+++ b/test/system/transactions_test.rb
@@ -196,10 +196,22 @@ class TransactionsTest < ApplicationSystemTestCase
     end
   end
 
+  test "transfers should always sum to zero" do
+    asset_account = accounts(:other_asset)
+    investment_account = accounts(:investment)
+    outflow_entry = create_transaction("outflow", Date.current, 500, account: asset_account)
+    inflow_entry = create_transaction("inflow", 1.day.ago.to_date, -500, account: investment_account)
+    asset_account.auto_match_transfers!
+    visit transactions_url
+    within "#entry-group-" + Date.current.to_s + "-totals" do
+      assert_text "-$100.00" # transaction eleven from setup
+    end
+  end
+
   private
 
-    def create_transaction(name, date, amount, category: nil, merchant: nil, tags: [])
-      account = accounts(:depository)
+    def create_transaction(name, date, amount, category: nil, merchant: nil, tags: [], account: nil)
+      account ||= accounts(:depository)
 
       account.entries.create! \
         name: name,