test_pizza_price.py

import pytest

from order.models import Pizza, Topping


@pytest.mark.django_db
def test_pizza_price_with_toppings():
    # Preparation phase
    pizza = Pizza.objects.create(name='Margarita')
    topping1 = Topping.objects.create(description='Pizza sauce', price=1.5)
    topping2 = Topping.objects.create(description='Mozzarella', price=1.65)
    pizza.toppings.add(topping1)
    pizza.toppings.add(topping2)

    # Calculating results
    actual_price = float(pizza.total_price)
    expected_price = topping1.price + topping2.price

    # Assertion
    assert actual_price == expected_price


@pytest.mark.django_db
def test_pizza_price_without_toppings():
    # Preparation phase
    pizza = Pizza.objects.create(name='Supreme')

    # Calculating results
    actual_price = float(pizza.total_price)
    expected_price = 0

    # Assertion
    assert actual_price == expected_price