code-antipatterns

Context

• Analysis path: $1 (defaults to current directory if not specified)
• JS/TS files: !find . -type f \( -name "*.js" -o -name "*.ts" -o -name "*.jsx" -o -name "*.tsx" \) 2>/dev/null
• Vue files: !find . -name "*.vue" 2>/dev/null
• Python files: !find . -name "*.py" 2>/dev/null

Your Task

Perform comprehensive anti-pattern analysis using ast-grep and parallel agent delegation.

Analysis Categories

Based on the detected languages, analyze for these categories:

1. JavaScript/TypeScript Anti-patterns

   • Callbacks, magic values, empty catch blocks, console.logs
   • var usage, deprecated patterns

2. Async/Promise Patterns

   • Unhandled promises, nested callbacks, missing error handling
   • Promise constructor anti-pattern

3. Framework-Specific (if detected)

   • Vue 3: Props mutation, reactivity issues, Options vs Composition API mixing
   • React: Missing deps in hooks, inline functions, prop drilling

4. TypeScript Quality (if .ts files present)

   • Excessive any types, non-null assertions, type safety issues

5. Code Complexity

   • Long functions (>50 lines), deep nesting (>4 levels), large parameter lists

6. Security Concerns

   • eval usage, innerHTML XSS, hardcoded secrets, injection risks

7. Memory & Performance

   • Event listeners without cleanup, setInterval leaks, inefficient patterns

8. Python Anti-patterns (if detected)

   • Mutable default arguments, bare except, global variables

Execution Strategy

CRITICAL: Use parallel agent delegation for efficiency.

Launch multiple specialized agents simultaneously:

## Agent 1: Language Detection & Setup (Explore - quick)
Detect project stack, identify file patterns, establish analysis scope

## Agent 2: JavaScript/TypeScript Analysis (code-analysis)
- Use ast-grep for structural pattern matching
- Focus on: empty catch, magic values, var usage, deprecated patterns

## Agent 3: Async/Promise Analysis (code-analysis)
- Unhandled promises, nested callbacks, floating promises
- Promise constructor anti-pattern

## Agent 4: Framework-Specific Analysis (code-analysis)
- Vue: props mutation, reactivity issues
- React: hooks dependencies, inline functions

## Agent 5: Security Analysis (security-audit)
- eval, innerHTML, hardcoded secrets, injection risks
- Use OWASP context

## Agent 6: Complexity Analysis (code-analysis)
- Function length, nesting depth, parameter counts
- Cyclomatic complexity indicators

ast-grep Pattern Examples

Use these patterns during analysis:

# Empty catch blocks
ast-grep -p 'try { $$$ } catch ($E) { }' --lang js

# Magic numbers
ast-grep -p 'if ($VAR > 100)' --lang js

# Console statements
ast-grep -p 'console.log($$$)' --lang js

# var usage
ast-grep -p 'var $VAR = $$$' --lang js

# TypeScript any
ast-grep -p ': any' --lang ts
ast-grep -p 'as any' --lang ts

# Vue props mutation
ast-grep -p 'props.$PROP = $VALUE' --lang js

# Security: eval
ast-grep -p 'eval($$$)' --lang js

# Security: innerHTML
ast-grep -p '$ELEM.innerHTML = $$$' --lang js

# Python: mutable defaults
ast-grep -p 'def $FUNC($ARG=[])' --lang py

Output Format

Consolidate findings into this structure:

## Anti-pattern Analysis Report

### Summary
- Total issues: X
- Critical: X | High: X | Medium: X | Low: X
- Categories with most issues: [list]

### Critical Issues (Fix Immediately)
| File | Line | Issue | Category |
|------|------|-------|----------|
| ... | ... | ... | ... |

### High Priority Issues
| File | Line | Issue | Category |
|------|------|-------|----------|
| ... | ... | ... | ... |

### Medium Priority Issues
[Similar table]

### Low Priority / Style Issues
[Similar table or summary count]

### Recommendations
1. [Prioritized fix recommendations]
2. [...]

### Category Breakdown
- **Security**: X issues (details)
- **Async/Promises**: X issues (details)
- **Code Complexity**: X issues (details)
- [...]

Optional Flags

• --focus <category>: Focus on specific category (security, async, complexity, framework)
• --severity <level>: Minimum severity to report (critical, high, medium, low)
• --fix: Attempt automated fixes where safe

Post-Analysis

After consolidating findings:

1. Prioritize issues by impact and effort
2. Suggest which issues can be auto-fixed with ast-grep
3. Identify patterns that indicate systemic problems
4. Recommend process improvements (linting rules, pre-commit hooks)

See Also

• Skill: code-antipatterns-analysis – Pattern library and detailed guidance
• Skill: ast-grep-search – ast-grep usage reference
• Command: /code:review – Comprehensive code review
• Agent: security-audit – Deep security analysis
• Agent: code-refactoring – Automated refactoring