TDD Workflow

RED 🔴 - Write Failing Test

import { describe, it, expect } from 'vitest'
import { myFunction } from '../myFunction'

describe('myFunction', () => {
  it('should return expected result', () => {
    expect(myFunction('input')).toBe('expected')
  })
})

Run: pnpm test → Must see FAIL

GREEN 🟢 - Minimal Implementation

Write ONLY what makes the test pass. No extras. No "nice to haves."

Run: pnpm test → Must see PASS

REFACTOR 🔵 - Clean Up

Only after green. Run tests again.