Clean up unused application records (#24871)

spec/lib/vacuum/applications_vacuum_spec.rb

@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe Vacuum::ApplicationsVacuum do
+  subject { described_class.new }
+
+  describe '#perform' do
+    let!(:app1) { Fabricate(:application, created_at: 1.month.ago) }
+    let!(:app2) { Fabricate(:application, created_at: 1.month.ago) }
+    let!(:app3) { Fabricate(:application, created_at: 1.month.ago) }
+    let!(:app4) { Fabricate(:application, created_at: 1.month.ago, owner: Fabricate(:user)) }
+    let!(:app5) { Fabricate(:application, created_at: 1.month.ago) }
+    let!(:app6) { Fabricate(:application, created_at: 1.hour.ago) }
+
+    let!(:active_access_token) { Fabricate(:access_token, application: app1) }
+    let!(:active_access_grant) { Fabricate(:access_grant, application: app2) }
+    let!(:user) { Fabricate(:user, created_by_application: app3) }
+
+    before do
+      subject.perform
+    end
+
+    it 'does not delete applications with valid access tokens' do
+      expect { app1.reload }.to_not raise_error
+    end
+
+    it 'does not delete applications with valid access grants' do
+      expect { app2.reload }.to_not raise_error
+    end
+
+    it 'does not delete applications that were used to create users' do
+      expect { app3.reload }.to_not raise_error
+    end
+
+    it 'does not delete owned applications' do
+      expect { app4.reload }.to_not raise_error
+    end
+
+    it 'does not delete applications registered less than a day ago' do
+      expect { app6.reload }.to_not raise_error
+    end
+
+    it 'deletes unused applications' do
+      expect { app5.reload }.to raise_error ActiveRecord::RecordNotFound
+    end
+  end
+end