SI206 Homework 4-Food Truck Classes  Solution

For this assignment, you will be writing and correcting methods so that customers can successfully order and pay for food at a food truck festival using the new ordering system which has the server take your orders directly, who then passes on the orders to the trucks. You will also be writing and correcting test cases, so you can guarantee that every step from the order being taken to delivery is accurate and your customers are happy!

Review the starter code thoroughly before beginning this assignment, as understanding how the classes interact with each other is important. Take notes or draw a diagram if necessary. We cannot emphasize how important this step is.

Overview
Customer Class
The Customer class defines a customer who will order from the trucks. Each customer object has 2 instance variables: name (a string representing a customer’s name) and wallet (a float showing how much money is in the customer’s wallet). The Customer class also includes several methods: withdraw_money (which adds a passed amount to the wallet), make_order (which you will implement – see details below), _init_ , order_food (which takes a server , a truck, the food_name, and the quantity and places an order at that truck to be delivered by that server), and eat_food(which simulates a customer eating the food by printing out “Wow, that was tasty!”).
Server Class
The Server class defines a server at the festival. Each server object has 4 instance variables: name (string with the name of the server), money (a float for the amount of money the server has), food trucks (a list of food trucks objects the server takes order for), and service_fee (a float showing the fee for delivery), alongside several methods (see the code for details).
Truck Class
The Truck class defines a food truck. Each truck object has 4 instance variables: name (a string which is the name of the truck), inventory (a dictionary which holds the names of the foods as the keys and the quantities of each food as the values) money (a float for the amount of money the truck has) and cost (the cost to the customer for each food). You will be in charge of implementing the Truck class – see details below.


Tasks to Complete

● Complete the Customer Class
○ Complete the make_order() method in the Customer class. This method takes a server and an amount as parameters, and has the customer pay the server the specified amount using the receive_payment method in the server class (i.e., it deducts money from the customer’s wallet and adds it to the server). See the test cases under test_make_payment for clues on how this method should behave.

● Create and implement the Truck class with the following methods
○ A constructor (__init__ method) that initializes the instance variables name, inventory, cost per food (default = 7), and money (default = 700).
○ A process_order() method that takes in two values, the food name and the quantity. If the food truck has the food, it will decrease the quantity of that food in the inventory and increase the amount of money in the truck by the cost times the quantity.
○ A has_food() method that takes in two values, the food name and the quantity and returns ‘True’ if there is enough food left in the inventory.
○ A stock_up() method that takes in two values, the food name and the quantity. It will add the quantity to the existing quantity if the food exists in the inventory dictionary or add the food and quantity to the inventory dictionary otherwise.

○ A __str__ method that returns a string with the information in the instance variables using the format shown below:

“Hello, we are [NAME]. This is the current menu [INVENTORY KEYS AS LIST]. We charge $[COST] per item. We have $[MONEY] in total.”

Expected output for printing a truck object:


● Implement a Main() method
○ Create at least two inventory dictionaries with at least 3 different types of food. The dictionary keys are the food items and the values are the quantity for each item.
○ Create at least 2 Customer objects. Each should have a unique name and unique amount of money in their wallet .
○ Create at least 2 Truck objects. Each should have a unique name, inventory, money, and cost.
○ Create at least 2 Server objects. Each should have a unique name, money, food trucks, and service_fee.
○ Have each customer place at least one order (by calling order_food).


● Write and Correct Test Cases
○ Note: Many test cases have already been written for you. Please do not edit test cases outside of the ones below. As you are working on one test case, feel free to comment out the test cases that you are not working on.
o test_estimated_cost fails. What are the correct numbers to make this test pass?
Correct the mistakes in this test.
o Complete test_has_food, which tests the has_food method in the Truck class.
We have provided 3 scenarios for you to test.
o Complete test_order_food, which tests the order_food method in the Customer class. The order_food method places an order of food from a food truck to be delivered by a server, but only if several conditions are met: if the customer has enough money in their wallet to pay for the transaction, if the food truck has food in stock, and if the server serves that food truck.
When writing tests for test_order_food, please write comments for each test case describing what scenarios you are testing, similar to the comments in test_has_food
Example output for this test case:
Don't have enough money for that :( Please withdraw more money!
Our food truck has run out of [Food Item] :( Please try a different truck! Sorry, I don’t serve that food truck. Please try a different one!

○ Complete test_withdraw_money, this tests if the customer can add money into their wallet.

Grading Rubric (60 points)
Note that if you use hardcoding (specify expected values directly) in any of the methods by way of editing to get them to pass the test cases, or you edit any test cases other than the ones you have been directed to, you will NOT receive credit for those related portions.

Note - use the provided methods you will earn credit if you implement the functionality instead.

-15 points for correctly implementing the Truck class (3 points per method).
-5 points for correctly completing the make_order method in the Customer class. -5 points for creating the customer, server, and food truck objects in the main method and correctly placing an order for both customers.
-3 points for correcting test_estimated_cost
-15 points for writing non-trivial test methods for test_has_food (5 points per scenario correctly tested).
-15 points for writing non-trivial tests for test_order_food (at least three scenarios; 5 points per scenario correctly tested).
-2 points for writing a test case for test_withdraw_money
Extra Credit (6 points)
To gain extra credit on this assignment, do the following: (1) Add a 20% tip for the server when a customer makes an order. (2) Fix the test case to test that your make_order function properly includes a tip. Earn up to 3 points for each task (for 6 total).