Testing and quality

Prompt template:

I need to generate unit test cases for the following function:

// utils/calculateTotal.ts
export function calculateTotal(items: Item[]): number {
  if (!items || items.length === 0) return 0
  return items.reduce((sum, item) => {
    if (item.price && item.quantity) {
      return sum + item.price * item.quantity
    }
    return sum
  }, 0)
}

interface Item {
  price?: number
  quantity?: number
}

Please use Jest/Vitest to generate test cases, including:
- Normal case tests
- Boundary case tests (empty array, null, undefined)
- Exceptional case tests (missing price or quantity)
- Organize tests using describe and it
- Use clear test descriptions

// utils/calculateTotal.test.ts
import { describe, it, expect } from 'vitest'
import { calculateTotal } from './calculateTotal'

describe('calculateTotal', () => {
  it('should return 0 for empty array', () => {
    expect(calculateTotal([])).toBe(0)
  })

  it('should return 0 for null or undefined', () => {
    expect(calculateTotal(null as any)).toBe(0)
    expect(calculateTotal(undefined as any)).toBe(0)
  })

  it('should calculate total for valid items', () => {
    const items = [
      { price: 10, quantity: 2 },
      { price: 5, quantity: 3 }
    ]
    expect(calculateTotal(items)).toBe(35) // 10*2 + 5*3 = 35
  })

  it('should ignore items without price', () => {
    const items = [
      { price: 10, quantity: 2 },
      { quantity: 3 }
    ]
    expect(calculateTotal(items)).toBe(20)
  })

  it('should ignore items without quantity', () => {
    const items = [
      { price: 10, quantity: 2 },
      { price: 5 }
    ]
    expect(calculateTotal(items)).toBe(20)
  })

  it('should handle zero price or quantity', () => {
    const items = [
      { price: 0, quantity: 2 },
      { price: 10, quantity: 0 }
    ]
    expect(calculateTotal(items)).toBe(0)
  })
})

Prompt:

I need to generate integration test scenarios for the user registration API:

API: POST /api/users/register
Request body: { email, password, name }
Response: { id, email, name, createdAt }

Please generate test cases including:
- Successful registration scenario
- Email already exists scenario
- Insufficient password strength scenario
- Missing required field scenario
- Use the test database
- Clean up test data

Prompt:

I need to generate E2E tests for the shopping cart flow:

User flow:
1. Visit the homepage
2. Search for products
3. Add product to cart
4. View cart
5. Checkout
6. Fill in order information
7. Submit order

Please use Playwright to generate complete E2E test code, including:
- Page navigation
- Element locators
- User interactions
- Assertion checks
- Error handling