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[Test]
public void CantSetTooHighCreditLimitForCustomer()
{
    Customer newCustomer = _CreateACustomer("Ronneby');

    //Inject a stubbed version of CreditService
    //that won't allow a credit of more than 300.
    newCustomer.CreditService = new StubCreditService(300);

    newCustomer.CreditLimit = 1000;

    Assert.IsFalse(newCustomer.HasOKCreditLimit);
}

[Test]
public void CanIterateOverOrderLines()
{
    Customer newCustomer = _CreateACustomerAndAnOrder
        ("Ronneby", 420);

    Order newOrder = (Order)_repository.GetOrders
        (newCustomer)[0];

    foreach (OrderLine orderLine in newOrder.OrderLines)
        return;

    Assert.Fail("I shouldn't get this far");
}