test-rename-drift

Test Rename Drift

The Problem

When renaming a function, test files have references that survive find-and-replace:

// Old function: calculateTotal()
// New function: computeTotal()

// Find-and-replace catches: calculateTotal(
// But misses:
describe('calculateTotal', () => {  // Describe block
  // tests for calculateTotal    // Comment
  it('calculateTotal returns sum', () => { // It block text

The Solution

Grep for BOTH the old AND new name after renaming.

# After renaming calculateTotal → computeTotal

# Find remaining old references
grep -rn "calculateTotal" . --include="*.test.*" --include="*.spec.*"

# Verify new references exist
grep -rn "computeTotal" . --include="*.test.*" --include="*.spec.*"

Checklist

Location	Find Pattern	Replace?
Function calls	oldName(	✅ Auto
Import statements	import { oldName }	✅ Auto
Describe blocks	describe('oldName'	❌ Manual
It block text	it('oldName should'	❌ Manual
Comments	// oldName does X	❌ Manual
Variable names	const oldNameResult	Depends
Mock names	jest.mock('oldName')	❌ Manual
Snapshot files	Contains "oldName"	❌ Manual

Automated Check

// scripts/check-rename-drift.cjs
const oldName = process.argv[2];
const newName = process.argv[3];

const { execSync } = require('child_process');

const oldRefs = execSync(
  `grep -rn "${oldName}" . --include="*.test.*" --include="*.spec.*" || true`,
  { encoding: 'utf8' }
);

if (oldRefs.trim()) {
  console.error(`Found ${oldRefs.split('\n').length - 1} remaining references to "${oldName}":`);
  console.error(oldRefs);
  process.exit(1);
}

console.log(`No remaining references to "${oldName}" in test files.`);

Verification

# Run after any rename
node scripts/check-rename-drift.cjs oldFunctionName newFunctionName

# Should report: "No remaining references"

When to Apply

• After any function/class/method rename
• Before committing renamed code
• During code review of renames