Advanced Testing Patterns

Introduction

Real-world job testing requires handling time, stubbing external services, and verifying negative cases.

Key Concepts

• Time Helpers: travel_to, freeze_time for time-dependent tests.
• Stubbing: Replacing external calls with controlled responses.

Real World Context

A job calling Stripe needs stubbed API responses. A daily digest needs time-travel tests.

Deep Dive

Stubbing External Services

ruby
test "syncs customer to Stripe" do
  Stripe::Customer.stub(:create, OpenStruct.new(id: "cus_123")) do
    SyncToStripeJob.perform_now(user.id)
  end
  assert_equal "cus_123", user.reload.stripe_customer_id
end

Negative Tests

ruby
test "no job for deactivated users" do
  assert_no_enqueued_jobs do
    OnboardingJob.perform_now(deactivated_user.id)
  end
end

Queue Assertions

ruby
test "enqueues to critical queue" do
  assert_enqueued_with(job: PaymentJob, queue: "critical") do
    PaymentService.charge(order)
  end
end

Common Pitfalls

1. Testing against real external services — Slow, flaky, costly.
2. Not testing discard paths — Verify discard_on side effects.

Best Practices

1. Stub all external services.
2. Test every retry_on and discard_on path.

Summary

• Stub external services for reliable tests.
• Write negative tests for skip conditions.
• Cover every error handling path.

test "schedules follow-up 3 days later" do
  freeze_time do
    assert_enqueued_with(job: FollowUpJob, at: 3.days.from_now) do
      OnboardingJob.perform_now(user.id)
    end
  end
end