2nd/10_Wiki/Topics/Architecture/Automated Refactoring Tools.md

---
id: wiki-2026-0508-automated-refactoring-tools
title: Automated Refactoring Tools
category: 10_Wiki/Topics
status: verified
canonical_id: self
aliases: [Refactoring Tools, IDE Refactoring, Codemod Tools]
duplicate_of: none
source_trust_level: A
confidence_score: 0.9
verification_status: applied
tags: [refactoring, tooling, ast, codemod]
raw_sources: []
last_reinforced: 2026-05-10
github_commit: pending
tech_stack:
  language: typescript
  framework: ts-morph,jscodeshift,comby,ast-grep
---

# Automated Refactoring Tools

## 매 한 줄
> **"매 AST-level 의 transform — 매 sed 의 X, 매 syntax-aware 의 mass-edit"**. 매 IDE refactor (Rename · Extract) 의 80년대 Smalltalk 의 root, 2026 의 LLM-augmented codemod (Claude Opus 4.7 + ast-grep) 의 mainstream.

## 매 핵심

### 매 3 tier 의 tool
- **IDE-builtin**: IntelliJ · VS Code · Rider — 매 single-file 의 dominant.
- **Codemod**: jscodeshift · ts-morph · comby · ast-grep — 매 cross-cutting mass change.
- **LLM-driven**: Claude Code · Cursor · GitHub Copilot Workspace — 매 semantic-aware 의 modernization.

### 매 refactor 종류
- Rename (symbol-aware).
- Extract function/variable/component.
- Inline.
- Move (file/module).
- Change signature.
- Convert (e.g. `var → const`, `function → arrow`).

### 매 응용
1. 매 framework migration (Vue 2 → Vue 3, React class → hook).
2. API breaking change 의 fan-out fix.
3. Code style 의 mechanical enforcement.

## 💻 패턴

### ts-morph: rename + add property
```typescript
import { Project } from "ts-morph";

const project = new Project({ tsConfigFilePath: "tsconfig.json" });

for (const sf of project.getSourceFiles()) {
  for (const cls of sf.getClasses()) {
    if (cls.getName()?.endsWith("Service")) {
      cls.rename(cls.getName()!.replace(/Service$/, "Manager"));
      cls.addProperty({ name: "createdAt", type: "Date", initializer: "new Date()" });
    }
  }
}

await project.save();
```

### ast-grep: pattern → rewrite (yaml rule)
```yaml
id: useEffect-cleanup
language: tsx
rule:
  pattern: useEffect(() => { $$$BODY }, $DEPS)
fix: |
  useEffect(() => {
    $$$BODY
    return () => { /* cleanup */ };
  }, $DEPS)
```
```bash
ast-grep scan -r useEffect-cleanup.yml --update-all
```

### jscodeshift: Vue Options → Composition API
```javascript
export default function transformer(file, api) {
  const j = api.jscodeshift;
  const root = j(file.source);

  root.find(j.ObjectExpression)
    .filter(p => p.node.properties.some(pr => pr.key?.name === "data"))
    .forEach(path => {
      // emit setup() function with refs
      // ...
    });

  return root.toSource();
}
```
```bash
jscodeshift -t vue-comp-api.js src/
```

### comby (language-agnostic structural search)
```bash
comby 'console.log(:[args])' 'logger.debug(:[args])' .ts -i
```

### LLM codemod (Claude Opus 4.7) — semantic-aware
```python
import anthropic

client = anthropic.Anthropic()
SYSTEM = "You convert React class components to functional + hooks. Preserve behavior."

with open("UserCard.tsx") as f:
    src = f.read()

resp = client.messages.create(
    model="claude-opus-4-7",
    max_tokens=4096,
    system=SYSTEM,
    messages=[{"role": "user", "content": src}],
)
print(resp.content[0].text)
```

### IDE script: IntelliJ structural search
```text
$method$($args$) { $body$ }
→ Constraints: method matches ".*Async$"
→ Replace with: async $method$($args$) { $body$ }
```

## 매 결정 기준
| 상황 | Tool |
|---|---|
| 매 single-file rename in IDE | IDE builtin |
| TS-only · type-aware | ts-morph |
| TS/JS · less type-aware · faster | jscodeshift |
| Multi-language · structural | comby · ast-grep |
| 매 semantic refactor · framework migration | LLM codemod |
| Mass mechanical regex-safe | sed/perl (드물게) |

**기본값**: TypeScript 의 ts-morph, polyglot 의 ast-grep, 매 semantic 의 LLM.

## 🔗 Graph
- 부모: [[Refactoring_Best_Practices|Refactoring]] · [[AST_Traversal|Abstract-Syntax-Tree-Traversal]]
- 응용: [[Architecture_Refactor]]
- Adjacent: [[AI-Assisted Refactoring (AI 기반 리팩토링)]] · [[AST_Traversal]]

## 🤖 LLM 활용
**언제**: 매 semantic refactor (class→hook, callback→async/await), 매 deterministic rule 의 hard 의 case.
**언제 X**: 매 mechanical rename 의 case — IDE 가 cheaper · safer. LLM 의 hallucination risk 의 require code review.

## ❌ 안티패턴
- **Regex-only refactor**: 매 string match 의 false positive (comment · string literal).
- **Test 없음 refactor**: 매 mass codemod 의 test suite 의 gate 의 require.
- **PR 의 single huge codemod**: 매 review 의 X — file-by-file commit 의 split.
- **LLM output 의 blind merge**: 매 type-check + test 의 gate 의 mandatory.

## 🧪 검증 / 중복
- Verified (ts-morph docs, Meta jscodeshift, comby.dev, ast-grep.github.io, Anthropic Claude API docs).
- 신뢰도 A.

## 🕓 Changelog
| 날짜 | 변경 |
|---|---|
| 2026-05-08 | Phase 1 |
| 2026-05-10 | Manual cleanup — 3-tier taxonomy + ts-morph/ast-grep/comby/LLM examples |