AO3-7045 Use bigint for audits IDs

db/migrate/20251221104708_change_audits_id_to_bigint.rb

@@ -0,0 +1,11 @@
+class ChangeAuditsIdToBigint < ActiveRecord::Migration[7.1]
+  uses_departure! if Rails.env.staging? || Rails.env.production?
+
+  def up
+    change_column :audits, :id, "bigint NOT NULL AUTO_INCREMENT"
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration, "This migration cannot be reverted because we can't safely migrate to a smaller id"
+  end
+end

spec/models/user_spec.rb

@@ -1,6 +1,17 @@
 require "spec_helper"
 
 describe User do
+  describe "audits" do
+    let(:user) { create(:user) }
+
+    it "can have an id larger than unsigned int" do
+      audit = Audited::Audit.new(id: 5_294_967_295, auditable: user)
+
+      expect(audit).to be_valid
+      expect(audit.save).to be_truthy
+    end
+  end
+
   describe "validations" do
     context "with a forbidden user name" do
       let(:forbidden_username) { Faker::Lorem.characters(number: 8) }