test(engine): force overdue branch in alarm-during-sleep test with negative offset

[NathanFlurry]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[NathanFlurry]

• chore(kitchen-sink): configurable endpoint #4766 : 3 dependent PRs (#4754 , #4777 , #4778 )
• refactor(rivetkit-core): rename StopReason to ShutdownKind and kill enum fallthroughs #4765
• chore(envoy-client): log command and event payloads #4751
• fix(rivetkit): minor sleep-cleanup follow-ups #4761
• docs(rivetkit): clean up stale setPreventSleep references in docs and JSDoc #4760
• docs(rivetkit): document keepAwake/waitUntil counter-arm race and surface bridge errors #4759
• test(engine): force overdue branch in alarm-during-sleep test with negative offset #4758 👈 (View in Graphite)
• fix(rivetkit-core): return stopping not starting when sleep/destroy called mid-shutdown #4757
• test(rivetkit): remove sleepWithPreventSleep fixture and tests #4756
• test(engine): add regression test for alarm-during-sleep-transition race #4755
• test(rivetkit-core): cover sleep/destroy guards and prevent_sleep no-op #4750
• docs: add keepAwake vs waitUntil table and internal sleep-sequence invariants #4749
• feat(rivetkit): expose c.keepAwake(promise) through native path #4748
• refactor(rivetkit): deprecate setPreventSleep to no-op in TypeScript #4747
• fix(rivetkit-core): enumerate non-drained counters in grace deadline warn log #4746
• fix(rivetkit-core): abort graceful cleanup task when grace deadline elapses #4745
• fix(rivetkit-core): error on sleep/destroy before startup or already-requested #4743
• fix(rivetkit-core): cap SerializeState shutdown timeout at 15s #4742
• refactor(rivetkit-core): remove prevent_sleep field and deprecate set_prevent_sleep to no-op #4741
• fix(api-public): remove orphan import_export actors module #4764
• main

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[claude]

Code Review: PR #4758

Summary

This PR makes the alarm_overdue_during_sleep_transition_fires_via_reallocation test deterministic by replacing a timing-based approach (short 100ms alarm offset that races the scheduler) with a negative offset (-1000ms) that guarantees the alarm is already overdue when Decision::Sleep evaluates it. The #[ignore] attribute is removed as the test no longer depends on a timing race. This is a test-only change with no production code impact.

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Correctness

The core idea is sound. The alarm timestamp is computed as:

let alarm_time = get_current_timestamp_ms() + self.alarm_offset_ms;

With alarm_offset_ms = -1000, alarm_time is 1 second in the past at the moment on_start runs. By the time handle_stopped evaluates Decision::Sleep, now >= alarm_ts is trivially true on every run, eliminating the race entirely. This is the right approach.

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Potential Issue: Subscription Ordering Race

The subscribe_lifecycle_events() call still happens after ready_rx.await, which means the generation-0 actor has already called send_set_alarm(...) and send_sleep_intent(). With a negative offset, reallocation fires immediately after handle_stopped, so there is a window between ready_rx resolving and subscribe_lifecycle_events() executing during which the Started { generation: 1 } event could fire and be missed.

The comment says "Subscribe before the actor enters sleep," but the subscription happens after the ready signal, which comes from inside on_start for generation 0 - the same call that dispatches the sleep intent. This window is very small, but it is not zero.

A safer sequence would be:

1. Call subscribe_lifecycle_events() before create_actor.
2. Await ready_rx.
3. Then await the generation-1 Started event.

Whether this is a real concern depends on the channel buffer size of subscribe_lifecycle_events(). If the broadcast::Receiver buffers the event before the subscription is created, it will be received fine. But if the event is lagged/dropped, the test would time out instead of failing with a clear error.

Recommendation: Move subscribe_lifecycle_events() before create_actor to make the subscription ordering provably correct, matching the defensive pattern used elsewhere in the test suite.

---

Code Quality

• The updated doc comment is clearer and more accurate than the original. Explicitly mentioning the -1000ms offset is helpful.
• Removing #[ignore] is correct given the test is now deterministic.
• Inline comments are well-written and explain the intent clearly.

---

Minor Nit

There is no assertion that the actor did not enter sleep state. The test only asserts the positive path (generation-1 wake via reallocation). This is acceptable given the timeout semantics, but a brief comment explaining this choice would be helpful.

---

Summary

Severity	Issue
Minor	subscribe_lifecycle_events() is called after ready_rx.await; the generation-1 Started event could theoretically be missed before the subscription is registered. Consider subscribing before create_actor.
Nit	No comment explaining that the negative sleep path is implicitly tested via timeout.

The core change is correct and a clear improvement over the previous timing-dependent approach.

[github-actions]

Preview packages published to npm

Install with:

npm install rivetkit@pr-4758

All packages published as 0.0.0-pr.4758.f601302 with tag pr-4758.

Engine binary is shipped via @rivetkit/engine-cli on linux-x64-musl, linux-arm64-musl, darwin-x64, and darwin-arm64. Windows users should use the release installer or set RIVET_ENGINE_BINARY.

Docker images:

docker pull rivetdev/engine:slim-f601302
docker pull rivetdev/engine:full-f601302

Individual packages

npm install rivetkit@pr-4758
npm install @rivetkit/react@pr-4758
npm install @rivetkit/rivetkit-napi@pr-4758
npm install @rivetkit/workflow-engine@pr-4758