public void CalculateNewPrice_UsesRegularPrice_WhenNotBuyingEnough()
{
// buy up to 3.0 units, get up to 3.0 units free (100% off)
BuyNGetUpToMDiscountedWeighedGroceryItemSpecial special =
new BuyNGetUpToMDiscountedWeighedGroceryItemSpecial(3.0M, 100M);
Assert.AreEqual(2.00M, special.CalculateNewPrice(1.00M, 2.0M));
}
public void CalculateNewPrice_ExtraWeightIsDiscounted_WhenBuyingAnUnevenAmount()
{
// buy up to 3.0 units, get up to 3.0 units 25% off
BuyNGetUpToMDiscountedWeighedGroceryItemSpecial special =
new BuyNGetUpToMDiscountedWeighedGroceryItemSpecial(3.0M, 25M);
// 3.0 * 1.00 = 3.00
// 2.0 * 0.75 = 1.50
// = 4.50
Assert.AreEqual(4.50M, special.CalculateNewPrice(1.00M, 5.00M));
}
public void CalculateNewPrice_HalfTheWeightIsDiscounted_WhenBuyingTwiceTheRequiredAmount()
{
// buy up to 3.0 units, get up to 3.0 units 25% off
BuyNGetUpToMDiscountedWeighedGroceryItemSpecial special =
new BuyNGetUpToMDiscountedWeighedGroceryItemSpecial(3.0M, 25M);
// 3.0 * 1.00 = 3.00
// 3.0 * 0.75 = 2.25
// = 5.25
Assert.AreEqual(5.25M, special.CalculateNewPrice(1.00M, 6.0M));
}