def test_basket_discount_multiple_bundle_offers(self):
# With bundle offer on all shampoo buy 3 get the cheapest free
self.bundle_offer_all_shampoo = BundleOffer([self.test_products[3],
self.test_products[4],
self.test_products[5]
], 3)
# With bundle offer on small shampoo and sardines buy 2 get the cheapest free
self.bundle_offer_small_shampoo_and_sardines = BundleOffer([self.test_products[3],
self.test_products[2]
], 2)
self.test_basket = Basket(self.test_catalouge, [
self.bundle_offer_all_shampoo,
self.bundle_offer_small_shampoo_and_sardines
])
# Add 1 sardines
self.test_basket.add_product(self.test_products[2], 1)
# Add 3 small shampoo
self.test_basket.add_product(self.test_products[3], 3)
# Add 2 medium shampoo
self.test_basket.add_product(self.test_products[4], 2)
# Add 3 large shampoo
self.test_basket.add_product(self.test_products[5], 3)
# One large shampoo for free (3.5)
# Two small shampoo for free (4.00)
# Total: 7.5
self.assertEqual(self.test_basket.calculate_discount(), 7.5)
self.assertEqual(self.test_basket.calculate_total(),
round_half_up(self.test_products[2].price +
self.test_products[3].price * 3 +
self.test_products[4].price * 2 +
self.test_products[5].price * 3 -
self.test_basket.calculate_discount(), 2))
def test_basket_discount_percent_offer(self):
# With Sardines 25% discount
self.percentage_offer = PercentageOffer(self.test_products[2], 0.25)
self.test_basket = Basket(self.test_catalouge, [self.percentage_offer])
# Add 2 Baked Beans
self.test_basket.add_product(self.test_products[0], 2)
# Add 1 Biscuits
self.test_basket.add_product(self.test_products[1])
# Add 2 Sardines
self.test_basket.add_product(self.test_products[2], 2)
self.assertEqual(self.test_basket.calculate_discount(), 2 * round_half_up(self.test_products[2].price * 0.25, 2))
self.assertEqual(self.test_basket.calculate_total(),
round_half_up(self.test_products[0].price * 2 +
self.test_products[1].price +
self.test_products[2].price * 2 -
self.test_basket.calculate_discount(), 2))
def test_percentage_offer_discount(self):
# Baked Beans buy one get one free
self.test_offer = PercentageOffer(self.test_products[0], 0.25)
self.test_basket = Basket(self.test_catalouge)
self.assertEqual(self.test_offer.get_discount(self.test_basket.products)[0], 0.00)
self.test_basket.add_product(self.test_products[0], 1)
self.assertEqual(self.test_offer.get_discount(
self.test_basket.products)[0],
round_half_up(self.test_products[0].price * 0.25, 2)
)
# Add 1 more Baked Beans for a total of 2
self.test_basket.add_product(self.test_products[0], 1)
self.assertEqual(self.test_offer.get_discount(
self.test_basket.products)[0],
round_half_up(self.test_products[0].price * 0.25, 2)
)
def calculate_total(self):
"""
Calculates the total that applies to the items currently in the basket after applied discounts
---
Returns:
float, the total that applies to the items currently in the basket after applied discounts
"""
return round_half_up(
self.calculate_subtotal() - self.calculate_discount(), 2)
def test_basket_discount_percent_and_buy_2_get_1_free_offers(self):
# With Baked Beans buy 2 get 1 free and 25% discount
self.buy_and_get_free_offer = BuyAndGetFreeOffer(self.test_products[0], 2, 1)
self.percentage_offer = PercentageOffer(self.test_products[0], 0.25)
self.test_basket = Basket(self.test_catalouge, [self.buy_and_get_free_offer, self.percentage_offer])
# Add 4 Baked Beans
self.test_basket.add_product(self.test_products[0], 4)
# Add 1 Biscuits
self.test_basket.add_product(self.test_products[1])
# Baked Beans Buy 2 get one free: 0.99
# Baked Beans 25% percent discount: 0.99 * 0.25 = 0.25
# Total: 0.99 + 0.25 = 1.24
self.assertEqual(self.test_basket.calculate_discount(), 1.24)
self.assertEqual(self.test_basket.calculate_total(),
round_half_up(self.test_products[0].price * 4 +
self.test_products[1].price -
self.test_basket.calculate_discount(), 2))
# Add 4 Baked Beans
self.test_basket.add_product(self.test_products[0], 4)
# Buy 2 get 1 free twice: 0.99 * 2 = 1.98
# Percentage discount on remaining 2: 0.99 * 0.25 * 2 = 0.50
# total: 1.98 + 0.50 = 2.48
self.assertEqual(self.test_basket.calculate_discount(), 2.48)
self.assertEqual(self.test_basket.calculate_total(),
round_half_up(self.test_products[0].price * 8 +
self.test_products[1].price -
self.test_basket.calculate_discount(), 2))
# With Baked Beans buy 2 get 1 free and 50% discount
self.buy_and_get_free_offer = BuyAndGetFreeOffer(self.test_products[0], 2, 1)
self.percentage_offer = PercentageOffer(self.test_products[0], 0.50)
self.test_basket = Basket(self.test_catalouge, [self.buy_and_get_free_offer, self.percentage_offer])
# Add 4 Baked Beans
self.test_basket.add_product(self.test_products[0], 4)
# Add 1 Biscuits
self.test_basket.add_product(self.test_products[1])
# Baked Beans Buy 2 get one free: 0
# Baked Beans 50% percent discount: 0.99 * 0.5 = 2.00
# Total: 2.00
self.assertEqual(self.test_basket.calculate_discount(), 2.00)
self.assertEqual(self.test_basket.calculate_total(),
round_half_up(self.test_products[0].price * 4 +
self.test_products[1].price -
self.test_basket.calculate_discount(), 2))
def calculate_discount(self):
"""
Calculates the total discount that applies to the items currently in the basket
---
Returns:
float, the total discount that applies to the items currently in the basket
"""
products_for_discount = Basket.get_basket_products_copy(self.products)
best_discount, best_products_used = self.__search_best_offer(
self.offers, products_for_discount)
return round_half_up(best_discount, 2)
def calculate_subtotal(self):
"""
Calculates the subtotal for the items currently in the basket
---
Returns:
float, the subtotal for the items currently in the basket
"""
subtotal = 0
for product_name in self.products:
price = self.products[product_name].product.price
quantity = self.products[product_name].quantity
subtotal += price * quantity
return round_half_up(subtotal, 2)
def test_basket_discount_buy_2_get_1_free(self):
# With Baked Beans buy 2 get 1 free
self.buy_and_get_free_offer = BuyAndGetFreeOffer(self.test_products[0], 2, 1)
self.test_basket = Basket(self.test_catalouge, [self.buy_and_get_free_offer])
# Add 4 Baked Beans
self.test_basket.add_product(self.test_products[0], 4)
# Add 1 Biscuits
self.test_basket.add_product(self.test_products[1])
self.assertEqual(self.test_basket.calculate_discount(), 0.99)
# Add 4 Baked Beans
self.test_basket.add_product(self.test_products[0], 4)
self.assertEqual(self.test_basket.calculate_discount(), 1.98)
self.assertEqual(self.test_basket.calculate_total(),
round_half_up(self.test_products[0].price * 8 +
self.test_products[1].price -
self.test_basket.calculate_discount(), 2))
def test_basket_discount_all_offers(self):
# With bundle offer on all shampoo buy 3 get the cheapest free
self.bundle_offer_all_shampoo = BundleOffer([self.test_products[3],
self.test_products[4],
self.test_products[5]
], 3)
# With bundle offer on small shampoo and sardines buy 2 get the cheapest free
self.bundle_offer_small_shampoo_and_sardines = BundleOffer([self.test_products[3],
self.test_products[2]
], 2)
self.buy_and_get_free_offer_baked_beans = BuyAndGetFreeOffer(self.test_products[0], 2, 1)
self.percentage_offer_baked_beans = PercentageOffer(self.test_products[0], 0.25)
self.test_basket = Basket(self.test_catalouge, [
self.bundle_offer_all_shampoo,
self.bundle_offer_small_shampoo_and_sardines,
self.buy_and_get_free_offer_baked_beans,
self.percentage_offer_baked_beans
])
# Add 4 Baked Beans
self.test_basket.add_product(self.test_products[0], 4)
# Add 1 Biscuits
self.test_basket.add_product(self.test_products[1])
# Add 1 sardines
self.test_basket.add_product(self.test_products[2], 1)
# Add 3 small shampoo
self.test_basket.add_product(self.test_products[3], 3)
# Add 2 medium shampoo
self.test_basket.add_product(self.test_products[4], 2)
# Add 3 large shampoo
self.test_basket.add_product(self.test_products[5], 3)
# Baked Beans Buy 2 get one free: 0.99
# Baked Beans 25% percent discount: 0.99 * 0.25 = 0.25
# One large shampoo for free (3.5)
# Two small shampoo for free (4.00)
# Total: 7.5 + 0.99 + 0.25 = 8.74
self.assertEqual(self.test_basket.calculate_discount(), 8.74)
self.assertEqual(self.test_basket.calculate_total(),
round_half_up(self.test_products[0].price * 4 +
self.test_products[1].price +
self.test_products[2].price +
self.test_products[3].price * 3 +
self.test_products[4].price * 2 +
self.test_products[5].price * 3 -
self.test_basket.calculate_discount(), 2))
def get_discount(self, basket_products):
"""
Given a dict of BaksetProducts, get the next best discount
---
Params:
basket_products: dict, the basket_products to calculate the next best discount from
---
Returns:
float, the next best discount
dict, dict of product names(key) and their quantity(value) used in the discount
"""
discount = 0
if (self.product in basket_products
and basket_products[self.product].quantity >= 1):
discount = basket_products[
self.product].product.price * self.discount_percent
return round_half_up(discount, 2), {self.product: 1}
return discount, {}
def test_basket_discount_bundle_offer(self):
# With bundle offer on all shampoo buy 3 get the cheapest free
self.test_offer = BundleOffer([self.test_products[3],
self.test_products[4],
self.test_products[5]
], 3)
self.test_basket = Basket(self.test_catalouge, [self.test_offer])
# Add 2 small shampoo
self.test_basket.add_product(self.test_products[3], 2)
# Add 1 medium shampoo
self.test_basket.add_product(self.test_products[4])
# Add 3 large shampoo
self.test_basket.add_product(self.test_products[5], 3)
# One large shampoo for free (3.5) and One small shampoo for free (2.00)
# Total: 5.5
self.assertEqual(self.test_basket.calculate_discount(), 5.5)
self.assertEqual(self.test_basket.calculate_total(),
round_half_up(self.test_products[3].price * 2 +
self.test_products[4].price +
self.test_products[5].price * 3 -
self.test_basket.calculate_discount(), 2))