test(sandbox): exercise active create handoff

[apurvvkumaria]

Summary

Tests now exercise the serialized create handoff added by #8729 at the actual lifecycle boundary. This also fixes the late shard-12 failure where the integration fixture never reported that its fake create process exited after SIGTERM.

Related Issue

Follow-up to #8729 and its CodeRabbit ordering finding.

Changes

• Invoke the captured create poll before the mocked stream resolves and assert the poll, stream completion, and deferred ensureApplied() order.
• Make the existing process-group fixture emit the fake create child's close event after SIGTERM, matching the ownership-release contract.
• Assert that the waited-for stream is not detached, with no production-code changes or new test files.

Type of Change

• Code change (feature, bug fix, or refactor)
• Code change with doc updates
• Doc only (prose changes, no code sample modifications)
• Doc only (includes code sample changes)

Quality Gates

• Tests added or updated for changed behavior
• Existing tests cover changed behavior — justification:
• Tests not applicable — justification:
• Docs updated for user-facing behavior changes
• Docs not applicable — justification: Test fixtures now match the already-merged ownership contract; no production behavior or user-facing surface changes.
• Sensitive paths changed (security, policy, credentials, preflight, onboarding, inference, runner, sandbox, or messaging)
• Sensitive-path review completed or maintainer-approved waiver recorded — reviewer/approval link/justification: Test-only changes preserve the fail-closed create timeout, simulate only the expected process exit, and do not alter production lifecycle, rollback, readiness, or compatibility behavior.
• Non-success, skipped, or missing CI check accepted by maintainer — check name, approval link, and follow-up issue:

Documentation Writer Review

• Documentation writer subagent reviewed the completed changes
• Result: no-docs-needed
• Evidence: No documentation paths changed. Existing docs/get-started/quickstart.mdx and docs/reference/commands.mdx already describe the unchanged ready and recreation contract.
• Agent: Codex Desktop

DGX Station Hardware Evidence

• Tested on DGX Station
• Tested commit:
• Station profile/scenario:
• Result:
• Supporting evidence:

Verification

• PR description includes a Signed-off-by: line and every commit appears as Verified in GitHub
• Normal pre-commit, commit-msg, and pre-push hooks passed, or npm run validate:pr passed after refreshing origin/main when hooks were skipped or unavailable
• Targeted behavior tests pass for the current change set, or tests are marked not applicable above — command/result or justification: npx vitest run --project cli src/lib/onboard/sandbox-gpu-create-flow.test.ts src/lib/sandbox/create-stream.test.ts (56 passed); npx vitest run --project integration test/onboard-sandbox-recreation.test.ts -t "waits for the create stream to close" (1 passed); the refined deferred-boundary test passed again after review feedback.
• Applicable broad gate passed — npm test for broad runtime/test-harness changes; npm run check for repo-wide validation/coverage changes — command/result: Not applicable; this is a two-test fixture correction protected by targeted tests and normal hooks.
• Quality Gates section completed with required justifications or waivers
• No secrets, API keys, or credentials committed
• npm run docs builds without warnings (doc changes only)
• Doc pages follow the style guide (doc changes only)
• New doc pages include SPDX header and frontmatter (new pages only)

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Signed-off-by: Apurv Kumaria akumaria@nvidia.com

[coderabbitai]

📝 Walkthrough

Walkthrough

The tests verify that patch application waits for create completion and that sandbox recreation waits for the create stream to close. They also update child-process termination and cleanup expectations.

Changes

Sandbox creation handoff

Layer / File(s)	Summary
Deferred patch application src/lib/onboard/sandbox-gpu-create-flow.test.ts	The no-GPU recreation test records polling, create completion, and patch application order.
Create stream lifecycle test/onboard-sandbox-recreation.test.ts	The recreation tests require stream closure after readiness and verify child termination and cleanup behavior.

Estimated code review effort: 2 (Simple) | ~10 minutes

Possibly related PRs

• NVIDIA/NemoClaw#8583: Both PRs modify sandbox recreation and restart-safe polling tests.
• NVIDIA/NemoClaw#8729: Both PRs update GPU create-flow tests for deferred patch application.

Suggested labels: area: sandbox

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly describes the test changes for the active sandbox create handoff lifecycle.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch codex/8729-create-handoff-tests

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_{Comment @coderabbitai help to get the list of available commands.}

[github-code-quality]

Code Coverage Overview

Languages: TypeScript

TypeScript / code-coverage/plugin

The overall coverage in commit b16e532 in the codex/8729-create-ha... branch remains at 96%, unchanged from commit 273e521 in the main branch.

---

_{Updated August 10, 2026 11:31 UTC}

[github-actions]

PR Review Advisor — No blocking findings reported

Advisor assessment: No blocking advisor findings reported
Next action: No advisor follow-up needed.
Findings: 0 blockers · 0 warnings · 0 suggestions

Model lanes

• GPT-5.6 Terra (primary): Completed · high confidence · 0 blockers · 0 warnings · 0 suggestions
• Nemotron 3 Ultra (second opinion): Completed · high confidence · 0 blockers · 0 warnings · 0 suggestions
• Model comparison: normalized findings match; normalized terminology decisions differ; normalized E2E selections differ; severity counts match.

1 additional E2E selection from the second opinion

Advisory only. The primary lane did not select these E2E jobs or targets.

• gpu-e2e: The completed second-opinion lane identified E2E coverage that the primary lane omitted.

Second-opinion terminology and E2E selections are advisory. Live E2E does not run automatically for pull requests.

1 semantic terminology decision

Terminology decisions are advisory. They affect the assessment only when a separate finding identifies concrete semantic impact.

• established — create stream at test/onboard-sandbox-recreation.test.ts:1205: Keep `create stream` for the stream-based sandbox-create operation.

E2E guidance

Advisory only. A maintainer can dispatch the default E2E suite against this exact revision.

Recommended E2E: cloud-onboard

2 optional E2E recommendations

• onboard-repair
• onboard-resume

Workflow run details

This automated review informs maintainers. Warnings and suggestions do not require a response. A maintainer decides whether to merge.

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@src/lib/onboard/sandbox-gpu-create-flow.test.ts`:
- Around line 515-520: Update the streamSandboxCreate mock in the sandbox
creation flow test to return a deferred promise that remains pending after
invoking onPoll; assert patch.ensureApplied has not been called while that
promise is pending, then resolve the deferred promise and await the flow before
verifying completion.

🪄 Autofix

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Enterprise

Run ID: 66226845-c7a1-4247-93d4-c4070ed647af

📥 Commits

Reviewing files that changed from the base of the PR and between 273e521 and 70160ea.

📒 Files selected for processing (2)

• src/lib/onboard/sandbox-gpu-create-flow.test.ts
• test/onboard-sandbox-recreation.test.ts