perf(sync): optimize local entity lookup in collectUpdates

[d-oit]

Optimizes sync conflict resolution in src/lib/sync/bridge.ts by replacing O(N) linear array scans (locals.find(...)) in collectUpdates and applyConflictResolution with O(1) Map lookups. Added merge performance test suite.

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PR created automatically by Jules for task 6691177906816101431 started by @d-oit

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📝 Summary by GitNexus

Summary

A focused synchronization performance change with impact beyond the edited code, despite low file-level risk.

🟠 HIGH blast radius. A synchronization performance change centered on local entity lookup in collectUpdates, also touching applyConflictResolution, with one direct dependent.

The change is concentrated in src/lib/sync/bridge.ts, with src/lib/sync/merge.perf.test.ts also changed. The graph places the impact in Sync and Views, with 3 affected flows.

Review the lookup path in collectUpdates and the related changes in applyConflictResolution, then check the performance test. The file-level risk is LOW; the overall blast level is HIGH.

Added by GitNexus for PR #919. Edit freely — this block is replaced on the next review, everything above it is left untouched.

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Project	Deployment	Actions	Updated
do-knowledge-studio	Ready	Preview, v0	Oct 7, 2026 1:06am UTC

[github-actions]

Blocked merge diagnosis — blocked
⏳ Check run(s) still in progress: ["Dependency Verify","Unit Tests","Quality Gate","shellcheck","Codacy Static Code Analysis","Diagnose Blocked Merge State","Trivy Filesystem Security Scan","Dependency Advisory Audit","Shell Script Security Analysis","Infrastructure as Code Security","Secret Detection","commitlint","Analyze (actions)","Analyze (javascript-typescript)","GitNexus"]

[nexus-check]

GitNexus Review · PR #919

1 issue found across 1 file.

Summary

A focused synchronization performance change with impact beyond the edited code, despite low file-level risk.

🟠 HIGH blast radius. A synchronization performance change centered on local entity lookup in collectUpdates, also touching applyConflictResolution, with one direct dependent.

The change is concentrated in src/lib/sync/bridge.ts, with src/lib/sync/merge.perf.test.ts also changed. The graph places the impact in Sync and Views, with 3 affected flows.

Review the lookup path in collectUpdates and the related changes in applyConflictResolution, then check the performance test. The file-level risk is LOW; the overall blast level is HIGH.

🔀 Structural changes · perf-sync-collect-updates-map-lookup-6691177906816101431 → main

Both branches are separately indexed, so this compares their code graphs directly — what the diff cannot show.

Symbols added (2)

• src/lib/sync/merge.perf.test.ts::generateClaims
• src/lib/sync/merge.perf.test.ts::generateEntities

Full detail lives in the GitNexus check run for this commit.

[nexus-check]

🤖 Agent context for GitNexus Review · PR #919

This comment carries deterministic graph detail for coding agents and reviewers who want the receipts — the main review comment carries the human summary.

🟠 HIGH blast radius — this change reaches 1 downstream symbol across 2 modules; review the dependent list before merging. (driven by dependent/module count, not file risk)

Blast Level	Dependents	Modules	Files
🟠 HIGH	1	2	2

What changed

Symbol Changes (2)

Kind	Symbol	Location
Function	applyConflictResolution	src/lib/sync/bridge.ts:223
Function	collectUpdates	src/lib/sync/bridge.ts:259

Changed Files (2)

File	Status
src/lib/sync/bridge.ts	🟡 modified
src/lib/sync/merge.perf.test.ts	🟢 added

What it affects

Architecture Impact

Module	Hits	Direct
Sync	2	⚪
Views	1	🟢

Blast Radius

Depth	Count
d1 (direct)	1
d2 (indirect)	0
d3 (transitive)	0

Direct dependents (d1)

• src/components/studio/views/sync-view.tsx:323 · handleConflictResolve

Prompt for AI agents (1 issue)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.

<file name="src/lib/sync/merge.perf.test.ts">

<violation number="1" location="src/lib/sync/merge.perf.test.ts:115">
P2: Performance tests never enforce a runtime bound — Both tests are named as fast-performance checks, but they only print the measured duration and assert the merged item count. Any arbitrarily slow regression still passes, so these tests do not detect the performance regressions their names imply.
</violation>

</file>

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

🟢 Metrics 11 complexity · 0 duplication

Metric	Results
Complexity	11
Duplication	0

View in Codacy

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