public void Should_throw_ArgumentException_for_invalid_orderitem()
{
var subject = new BuyXItemsGetYFree("item-1", 2, 1);
var incorrectOrderItem = new OrderItem {
Identifier = "item-2", ItemCost = 10m, Quantity = 3
};
Assert.Throws <ArgumentException>(() => subject.CalculateItemPrice(incorrectOrderItem));
}
public void Should_return_false_for_less_than_x_items()
{
var subject = new BuyXItemsGetYFree("item-1", 2, 1);
var orderItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 1
};
Assert.IsFalse(subject.MatchesItem(orderItem));
}
public void Should_return_false_for_non_matched_items()
{
var subject = new BuyXItemsGetYFree("item-1", 2, 1);
var incorrectOrderItem = new OrderItem {
Identifier = "item-2", ItemCost = 10m, Quantity = 3
};
Assert.IsFalse(subject.MatchesItem(incorrectOrderItem));
}
public void Should_calculate_set_price_for_exact_sets()
{
var subject = new BuyXItemsGetYFree("item-1", 3, 2);
var firstOrderItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 5
};
var secondOrderItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 10
};
Assert.That(subject.CalculateItemPrice(firstOrderItem), Is.EqualTo(30m));
Assert.That(subject.CalculateItemPrice(secondOrderItem), Is.EqualTo(60m));
}
public void Should_return_true_for_at_least_x_items()
{
var subject = new BuyXItemsGetYFree("item-1", 2, 1);
var firstItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 2
};
var secondItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 3
};
var thirdItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 4
};
Assert.IsTrue(subject.MatchesItem(firstItem));
Assert.IsTrue(subject.MatchesItem(secondItem));
Assert.IsTrue(subject.MatchesItem(thirdItem));
}
public void Should_calculate_full_price_for_items_not_in_set()
{
var subject = new BuyXItemsGetYFree("item-1", 3, 2);
var firstOrderItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 5
};
var secondOrderItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 6
};
var thirdOrderItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 7
};
Assert.That(subject.CalculateItemPrice(firstOrderItem), Is.EqualTo(30m));
Assert.That(subject.CalculateItemPrice(secondOrderItem), Is.EqualTo(40m));
Assert.That(subject.CalculateItemPrice(thirdOrderItem), Is.EqualTo(50m));
}
public void Should_calculate_set_price_when_ordered_quantity_is_more_than_X_but_free_items_are_less_than_Y()
{
var subject = new BuyXItemsGetYFree("item-1", 3, 2);
var firstOrderItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 3
};
var secondOrderItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 4
};
var thirdOrderItem = new OrderItem {
Identifier = subject.ItemId, ItemCost = 10m, Quantity = 5
};
Assert.That(subject.CalculateItemPrice(firstOrderItem), Is.EqualTo(30m));
Assert.That(subject.CalculateItemPrice(secondOrderItem), Is.EqualTo(30m));
Assert.That(subject.CalculateItemPrice(thirdOrderItem), Is.EqualTo(30m));
}