⚡ Bolt: [성능 개선] StringBuilder 도입 및 Set을 통한 조회 성능 개선

[seonghobae]

💡 What: process_dir 내 HTML 문자열 생성 시 StringBuilder를 사용하도록 변경하고, process_ignore_file에서 반환하는 제외 파일 목록을 List에서 Set으로 변경했습니다.
🎯 Why: 기존 루프 내 += 연산자를 이용한 문자열 연결은 O(N^2)의 시간 복잡도를 가져 파일이 많은 디렉토리에서 심각한 병목을 유발합니다. 또한 제외 파일 검색 시 List를 사용하여 파일마다 O(M) 조회가 발생하던 부분을 O(1)로 단축했습니다.
📊 Impact: 디렉토리에 많은 파일과 무시 규칙이 있을 경우, 불필요한 메모리 할당이 제거되고 속도가 크게 향상됩니다.
🔬 Measurement: export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64 && ./gradlew test jacocoTestReport jacocoTestCoverageVerification 명령어를 통해 테스트 통과 및 코드 커버리지 유지를 확인했습니다.

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PR created automatically by Jules for task 4660377195156544588 started by @seonghobae

[google-labs-jules]

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[opencode-agent]

Pull request overview

OpenCode reviewed the current-head mergeability evidence and changed-file flow before approval, then found merge conflicts on the affected path.

Findings

1. HIGH Merge Conflict Guidance - Resolve the PR branch against the latest base branch

• Problem: GitHub reports mergeStateStatus DIRTY for this pull request.
• Root cause: Branch bolt-optimize-string-and-lookups-4660377195156544588 cannot be merged cleanly into master; the changed-file flow below shows which review/runtime path is blocked by the conflict.
• Fix: Merge or rebase the latest master into bolt-optimize-string-and-lookups-4660377195156544588, resolve conflict markers in the PR branch, rerun the focused checks, and push the same branch.
• Repair commands:

gh pr checkout 70 --repo ContextualWisdomLab/html4tree
git fetch origin master
git merge --no-ff origin/master  # or: git rebase origin/master
git status --short
# resolve files, then git add <resolved-files>
# merge path: git commit
# rebase path: git rebase --continue
git push origin HEAD:bolt-optimize-string-and-lookups-4660377195156544588
# rebase path only: git push --force-with-lease origin HEAD:bolt-optimize-string-and-lookups-4660377195156544588

• Regression test: Keep OpenCode approval gated on mergeability so model-output failures cannot approve a conflicted PR.

Change Flow DAG

flowchart LR
  PR["PR changed files"] --> Evidence["OpenCode bounded evidence"]
  Evidence --> S1["Changed file (2 files)"]
  S1 --> I1["repository behavior"]
  I1 --> Conflict["Merge conflict blocks this path"]
  Conflict --> V1["required checks"]

Loading

• Result: REQUEST_CHANGES
• Reason: mergeStateStatus is DIRTY; mergeable is CONFLICTING.
• Head SHA: 5a778fb42dd3528846f6d61da90eb4780ff401a8
• Workflow run: 28418163615
• Workflow attempt: 1

[opencode-agent]

OpenCode Review Overview

• Head SHA: 5a778fb42dd3528846f6d61da90eb4780ff401a8
• Workflow run: 28418163615
• Workflow attempt: 1
• Gate result: REQUEST_CHANGES (approval step)

Pull request overview

OpenCode reviewed the current-head mergeability evidence and changed-file flow before approval, then found merge conflicts on the affected path.

Findings

1. HIGH Merge Conflict Guidance - Resolve the PR branch against the latest base branch

• Problem: GitHub reports mergeStateStatus DIRTY for this pull request.
• Root cause: Branch bolt-optimize-string-and-lookups-4660377195156544588 cannot be merged cleanly into master; the changed-file flow below shows which review/runtime path is blocked by the conflict.
• Fix: Merge or rebase the latest master into bolt-optimize-string-and-lookups-4660377195156544588, resolve conflict markers in the PR branch, rerun the focused checks, and push the same branch.
• Repair commands:

gh pr checkout 70 --repo ContextualWisdomLab/html4tree
git fetch origin master
git merge --no-ff origin/master  # or: git rebase origin/master
git status --short
# resolve files, then git add <resolved-files>
# merge path: git commit
# rebase path: git rebase --continue
git push origin HEAD:bolt-optimize-string-and-lookups-4660377195156544588
# rebase path only: git push --force-with-lease origin HEAD:bolt-optimize-string-and-lookups-4660377195156544588

• Regression test: Keep OpenCode approval gated on mergeability so model-output failures cannot approve a conflicted PR.

Change Flow DAG

flowchart LR
  PR["PR changed files"] --> Evidence["OpenCode bounded evidence"]
  Evidence --> S1["Changed file (2 files)"]
  S1 --> I1["repository behavior"]
  I1 --> Conflict["Merge conflict blocks this path"]
  Conflict --> V1["required checks"]

Loading

• Result: REQUEST_CHANGES
• Reason: mergeStateStatus is DIRTY; mergeable is CONFLICTING.
• Head SHA: 5a778fb42dd3528846f6d61da90eb4780ff401a8
• Workflow run: 28418163615
• Workflow attempt: 1

Merge Conflict Guidance

• Current merge state: DIRTY
• Base branch: master
• Head branch: bolt-optimize-string-and-lookups-4660377195156544588
• Fix direction: merge or rebase origin/master into bolt-optimize-string-and-lookups-4660377195156544588, resolve conflict markers in the changed files, rerun the focused checks, then push the same branch.
• Repair commands:

gh pr checkout 70 --repo ContextualWisdomLab/html4tree
git fetch origin master
git merge --no-ff origin/master  # or: git rebase origin/master
git status --short
# resolve files, then git add <resolved-files>
# merge path: git commit
# rebase path: git rebase --continue
git push origin HEAD:bolt-optimize-string-and-lookups-4660377195156544588
# rebase path only: git push --force-with-lease origin HEAD:bolt-optimize-string-and-lookups-4660377195156544588

[seonghobae]

Closing as superseded by already-merged performance work (#20/#21). Current master already uses StringBuilder for generated HTML rows and Set membership for ignore exclusions.

[google-labs-jules]

Closing as superseded by already-merged performance work (#20/#21). Current master already uses StringBuilder for generated HTML rows and Set membership for ignore exclusions.

Understood. Acknowledging that this work is now obsolete and stopping work on this task.