ex6-totalCost.js

/*------------------------------------------------------------------------------
Full description at: https://github.com/HackYourFuture/Assignments/tree/main/1-JavaScript/Week3#exercise-6-total-cost-is

You want to buy a couple of things from the supermarket to prepare for a party.
After scanning all the items the cashier wants to give you the total price, but
the machine is broken! Let's write her a function that does it for her
instead!

1. Create an object named `cartForParty` with five properties. Each property
   should be a grocery item (like `beers` or `chips`) and hold a number value
   (like `1.75` or `0.99`).

2. Complete the function called `calculateTotalPrice`.

   - It takes one parameter: an object that contains properties that only contain
     number values.
   - Loop through the object and add all the number values together.
   - Return a string: "Total: €`amount`".

3. Complete the unit test functions and verify that all is working as expected.
-----------------------------------------------------------------------------*/

// Create an object with 5 grocery items
const cartForParty = {
  beers: 5.25,
  chips: 1.5,
  soda: 2.0,
  cookies: 3.75,
  cheese: 4.25,
};

// Function to calculate total price of items in an object
function calculateTotalPrice(cart) {
  let total = 0;

  // Loop through object values and sum them
  for (const item in cart) {
    if (cart.hasOwnProperty(item)) {
      total += cart[item];
    }
  }

  // Return formatted total
  return `Total: €${total.toFixed(2)}`;
}

// ! Test functions (plain vanilla JavaScript)
function test1() {
  console.log('\nTest 1: calculateTotalPrice should take one parameter');
  console.assert(calculateTotalPrice.length === 1);
}

function test2() {
  console.log('\nTest 2: return correct output when passed cartForParty');
  const expected = 'Total: €16.75';
  const actual = calculateTotalPrice(cartForParty);
  console.assert(
    actual === expected,
    `Expected "${expected}", but got "${actual}"`
  );
}

function test() {
  test1();
  test2();
}

test();