stores the heading where the user has voted

app/models/budget/ballot/line.rb

@@ -16,6 +16,7 @@ class Budget
       scope :by_investment, ->(investment_id) { where(investment_id: investment_id) }
 
       before_validation :set_denormalized_ids
+      after_save :store_user_heading
 
       def check_sufficient_funds
         errors.add(:money, "insufficient funds") if ballot.amount_available(investment.heading) < investment.price.to_i
@@ -37,6 +38,10 @@ class Budget
           self.group_id   ||= investment.try(:group_id)
           self.budget_id  ||= investment.try(:budget_id)
         end
+
+        def store_user_heading
+          ballot.user.update(balloted_heading_id: heading.id)
+        end
     end
   end
 end

db/migrate/20170514192303_add_balloted_heading_id_to_users.rb

@@ -0,0 +1,5 @@
+class AddBallotedHeadingIdToUsers < ActiveRecord::Migration
+  def change
+    add_column :users, :balloted_heading_id, :integer, default: nil
+  end
+end

db/schema.rb

@@ -1456,6 +1456,7 @@ ActiveRecord::Schema.define(version: 20190205131722) do
     t.boolean  "created_from_signature",                    default: false
     t.integer  "failed_email_digests_count",                default: 0
     t.text     "former_users_data_log",                     default: ""
+    t.integer  "balloted_heading_id"
     t.boolean  "public_interests",                          default: false
     t.boolean  "recommended_debates",                       default: true
     t.boolean  "recommended_proposals",                     default: true

spec/models/budget/ballot/line_spec.rb

@@ -44,6 +44,19 @@ describe Budget::Ballot::Line do
 
   end
 
+  describe "#store_user_heading" do
+
+    it "stores the heading where the user has voted" do
+      user = create(:user, :level_two)
+      investment = create(:budget_investment, :selected)
+      ballot = create(:budget_ballot, user: user, budget: investment.budget)
+
+      create(:budget_ballot_line, ballot: ballot, investment: investment)
+
+      expect(user.balloted_heading_id).to eq(investment.heading.id)
+    end
+  end
+
   describe "scopes" do
 
     describe "by_investment" do