Improve spec coverage for collection of workers/ classes (#27874)

spec/workers/backup_worker_spec.rb

@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe BackupWorker do
+  let(:worker) { described_class.new }
+  let(:service) { instance_double(BackupService, call: true) }
+
+  describe '#perform' do
+    before do
+      allow(BackupService).to receive(:new).and_return(service)
+    end
+
+    let(:backup) { Fabricate(:backup) }
+    let!(:other_backup) { Fabricate(:backup, user: backup.user) }
+
+    it 'sends the backup to the service and removes other backups' do
+      expect do
+        worker.perform(backup.id)
+      end.to change(UserMailer.deliveries, :size).by(1)
+
+      expect(service).to have_received(:call).with(backup)
+      expect { other_backup.reload }.to raise_error(ActiveRecord::RecordNotFound)
+    end
+
+    context 'when sidekiq retries are exhausted' do
+      it 'destroys the backup' do
+        described_class.within_sidekiq_retries_exhausted_block({ 'args' => [backup.id] }) do
+          worker.perform(backup.id)
+        end
+
+        expect { backup.reload }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+    end
+  end
+end