public async Task CustomerIsAddedSuccessfully()
{
MockUnitOfWOrk.Setup(p => p.CustomerRepository.Create(It.IsAny <Customer>()))
.Returns(() => TestCustomers[0]);
MockUnitOfWOrk.Setup(m => m.SaveAsync()).ReturnsAsync(() => new List <Guid>()
{
TestCustomers[0].Id
}.AsEnumerable());
var result = await SystemUnderTest.AddCustomerAsync(TestCustomers[0]);
Assert.Equal(TestCustomers[0].Id, result);
}
