test(server): cover raw OpenCode deltas through the adapter

[juliusmarminge]

The string-concatenation helper is exported only for direct unit-test assertions.

Make it private and remove those assertions. Keep snapshot reconciliation cases and the existing adapter-level delta regression.

Verification: Both focused snapshot/delta regression tests passed before and after. Targeted lint and diff checks passed.

Model: gpt-6 astra. Harness: Codex in T3 Code.

---

Note

Low Risk
Test and visibility-only change; adapter streaming behavior is unchanged and still covered indirectly.

Overview
Encapsulates appendOpenCodeAssistantTextDelta by removing its export in OpenCodeAdapter.ts; the adapter still uses it for streaming assistant text.

Tests no longer import or assert on raw delta concatenation. The effect test is renamed to focus on mergeOpenCodeAssistantText snapshot reconciliation (initial emit, append suffix, replacement, stale snapshot).

^{Reviewed by Cursor Bugbot for commit ec01c6c. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Make appendOpenCodeAssistantTextDelta file-local and test deltas via adapter

Changes appendOpenCodeAssistantTextDelta from an exported function to a file-local helper in OpenCodeAdapter.ts. Refactors the reconciliation test in OpenCodeAdapter.test.ts to verify assistant-text snapshots through mergeOpenCodeAssistantText instead of testing the helper directly. Removes the overlap-delta scenario and keeps assertions for initial, appended, changed, and stale snapshots.

^{Macroscope summarized ec01c6c.}

[macroscopeapp]

Approvability

Verdict: Approved at ec01c6c

Macroscope's review found this PR approvable — This is a small test and encapsulation cleanup. The adapter logic is unchanged, the helper remains used internally, and no other repository consumers depend on the removed export.

^{You can add or adjust custom eligibility rules. Learn more.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.6 KiB	13.6 KiB	+16 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	+20 B (+0.3%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.1 KiB	57.1 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.5 KiB	−38 B (−0.3%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	+10 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.6 KiB	6.5 KiB	−48 B (−0.7%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.9 KiB	57.8 KiB	−88 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	8	−2 (−20.0%)	21	✅

Baseline: dfc70a3 · PR result: ec01c6c · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 113.8 KiB
• Claude decoded thread snapshot: 114.5 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

[juliusmarminge]

The failed Test job reports an unhandled cancelAnimationFrame is not defined from the file-editor worker tests after teardown. Those tests and the Pierre dependency/patch are unchanged by this PR. Both focused file-editor suites pass on unchanged main (14 tests); a lifecycle reproduction also confirms that worker termination can leave a test-owned setImmediate callback queued after vi.unstubAllGlobals().

Requested one rerun of the failed job. No assertions were deleted, checks skipped, or production code changed to address this failure. This rerun does not fix the existing teardown race.

Model: gpt-6 astra. Harness: Codex in T3 Code.