dead-code-detector

// Unused
const result = calculate();
const unused = 42; // Never referenced
 
// Dead assignment
let value = 10;
value = 20; // First assignment is dead

function example() {
  return true;
  console.log('Never executes'); // Dead code
}
 
if (false) {
  // Dead code block
}

// Private function never called
function helperFunction() {
  // ...
}
 
// Exported but not used anywhere
export function unusedExport() {
  // ...
}

@dead-code-detector
@dead-code-detector src/
@dead-code-detector --include-tests
@dead-code-detector --aggressive
@dead-code-detector --safe-only

# Dead Code Detection Report
 
## Summary
- Total unused items: 47
- Safe to remove: 32
- Needs review: 15
- Potential savings: ~1,200 lines
 
## Safe to Remove (32)
 
### Unused Imports (12)
- src/utils/helpers.js:3
  `import { oldFunction } from './legacy'`
 
- src/components/Button.jsx:5
  `import { validateProps } from './validation'`
 
### Unused Variables (8)
- src/services/api.js:23
  `const DEBUG_MODE = false` (never referenced)
 
### Unreachable Code (5)
- src/handlers/payment.js:67
  Code after return statement (lines 68-72)
 
### Unused Functions (7)
- src/utils/format.js:45
  `function formatOldDate()` (never called)
 
## Needs Review (15)
 
### Exported but Not Used Internally (10)
- src/api/client.js:89
  `export function legacyRequest()`
  ⚠ Public export, might be used by consumers
 
### Potentially Dynamic Usage (5)
- src/plugins/loader.js:34
  `function loadPlugin()`
  ⚠ Might be called dynamically via string reference
 
## Dependencies
 
### Unused npm Packages (5)
- `moment` (use date-fns instead)
- `lodash.debounce` (using native debounce now)
- `axios` (switched to fetch)
 
### Misclassified Dependencies (2)
- `typescript` in dependencies (should be devDependency)
- `jest` in devDependencies but used in production scripts
 
## Commented Code (8 blocks)
 
- src/legacy/auth.js:120-145 (25 lines commented)
- src/components/Modal.jsx:67-82 (15 lines commented)
 
## Recommendations
 
1. **Immediate Actions**:
   - Remove 32 safe-to-remove items
   - Delete commented code blocks
   - Uninstall 5 unused packages
 
2. **Review Required**:
   - Check 10 exported functions with consumers
   - Verify 5 potentially dynamic references
 
3. **Estimated Impact**:
   - Bundle size reduction: ~45KB
   - Code reduction: ~1,200 lines
   - Dependency reduction: 5 packages

// Might look unused but called dynamically
const handlers = {
  onClick: handleClick,
  onHover: handleHover
};
 
// Called via string
window['initApp']();

// Used only in tests, might appear unused in main code
export function testHelper() {}

// Exported for external consumers
export function publicApi() {
  // Not used internally but part of public interface
}