fix: Add validation to ensure transfer inflow is after outflow

app/controllers/account/transactions_controller.rb

@@ -28,6 +28,8 @@ def mark_transfers
            .mark_transfers!
 
     redirect_back_or_to transactions_url, notice: t(".success")
+  rescue ActiveRecord::RecordInvalid => e
+    redirect_back_or_to transactions_url, alert: e.message
   end
 
   def unmark_transfers

app/models/account/entry.rb

@@ -102,7 +102,7 @@ def mark_transfers!
       update_all marked_as_transfer: true
 
       # Attempt to "auto match" and save a transfer if 2 transactions selected
-      Account::Transfer.new(entries: all).save if all.count == 2
+      Account::Transfer.new(entries: all).save! if all.count == 2
     end
 
     def bulk_update!(bulk_update_params)

app/models/account/transfer.rb

@@ -2,7 +2,7 @@ class Account::Transfer < ApplicationRecord
   has_many :entries, dependent: :destroy
 
   validate :net_zero_flows, if: :single_currency_transfer?
-  validate :transaction_count, :from_different_accounts, :all_transactions_marked
+  validate :transaction_count, :from_different_accounts, :inflow_after_outflow, :all_transactions_marked
 
   def date
     outflow_transaction&.date
@@ -99,6 +99,14 @@ def from_different_accounts
       errors.add :entries, :must_be_from_different_accounts if accounts.size < entries.size
     end
 
+    def inflow_after_outflow
+      return unless inflow_transaction && outflow_transaction
+
+      if inflow_transaction.date < outflow_transaction.date
+        errors.add :entries, :inflow_must_be_after_outflow
+      end
+    end
+
     def net_zero_flows
       unless entries.sum(&:amount).zero?
         errors.add :entries, :must_have_an_inflow_and_outflow_that_net_to_zero

config/locales/models/account/transfer/en.yml

@@ -15,3 +15,4 @@ en:
               must_have_an_inflow_and_outflow_that_net_to_zero: must have an inflow
                 and outflow that net to zero
               must_have_exactly_2_entries: must have exactly 2 entries
+              inflow_must_be_after_outflow: inflow must be after outflow

test/system/transfers_test.rb

@@ -60,6 +60,38 @@ class TransfersTest < ApplicationSystemTestCase
     end
   end
 
+  test "cannot create transfer where inflow date is before outflow date" do
+    outflow = accounts(:depository).entries.create!(
+      name: "Outflow from checking account",
+      date: Date.current,
+      amount: 100,
+      currency: "USD",
+      entryable: Account::Transaction.new
+    )
+
+    inflow = accounts(:credit_card).entries.create!(
+      name: "Inflow to cc account",
+      date: 1.day.ago.to_date,  # Date before outflow
+      amount: -100,
+      currency: "USD",
+      entryable: Account::Transaction.new
+    )
+
+    visit transactions_url
+
+    transaction_entry_checkbox(inflow).check
+    transaction_entry_checkbox(outflow).check
+
+    bulk_transfer_action_button.click
+    click_on "Mark as transfers"
+
+    assert_text "Validation failed: Entries inflow must be after outflow"
+
+    # Verify the entries weren't linked as a transfer
+    assert_nil outflow.reload.transfer_id
+    assert_nil inflow.reload.transfer_id
+  end
+
   test "can mark a single transaction as a transfer" do
     txn = @user.family.entries.account_transactions.reverse_chronological.first