需要用 mock 測試的 sample

gistfile1.cs

using System;
using System.Collections.Generic;

namespace MessageHandler.Test
{
    public class MyService
    {
        private ICustomerDao _customerDao;

        public MyService(ICustomerDao customerDao)
        {
            this._customerDao = customerDao;
        }

        // 該如何測試 MyMethod？
        public void MyMethod()
        {
            var customers = GetCustomers();
            foreach (var customer in customers)
            {
                if (customer.IsMale)
                {
                    this._customerDao.Insert(customer);
                }
            }
        }

        private IEnumerable<Customer> GetCustomers()
        {
            yield return new Customer { Id = 1, IsMale = true };
            yield return new Customer { Id = 2, IsMale = false };
            yield return new Customer { Id = 3, IsMale = true };
            yield return new Customer { Id = 4, IsMale = false };
            yield return new Customer { Id = 5, IsMale = true };
        }
    }

    public class Customer
    {
        public int Id { get; set; }

        public bool IsMale { get; set; }
    }

    public interface ICustomerDao
    {
        void Insert(Customer customer);
    }

    public class CustomerDao : ICustomerDao
    {
        public void Insert(Customer customer)
        {
            throw new NotImplementedException();
        }
    }
}