Task

Sales Taxes

Basic‌ ‌sales‌ ‌tax‌ ‌is‌ ‌applicable‌ ‌at‌ ‌a‌ ‌rate‌ ‌of‌ ‌10%‌ ‌on‌ all‌ ‌goods,‌ ‌except‌ ‌books,‌ ‌food,‌ ‌and‌ ‌medical‌‌ products‌ ‌that‌ ‌are‌ ‌exempt.‌ ‌Import‌ ‌duty‌ ‌is‌ ‌an‌ ‌additional‌ ‌sales‌ ‌tax‌ ‌applicable‌ ‌on‌ ‌all‌ ‌imported‌ ‌goods‌ ‌at‌ ‌a‌ ‌rate‌ ‌of‌ ‌5%,‌ ‌with‌ ‌no‌ ‌exemptions.‌ ‌When‌ ‌I‌ ‌purchase‌ ‌items‌‌ I‌ ‌receive‌ ‌a‌ ‌receipt‌ ‌which‌ ‌lists‌ ‌the‌ ‌name‌ ‌of‌ ‌all‌ ‌the‌ ‌items‌ ‌and‌ ‌their‌ ‌price‌ ‌(including‌ ‌tax),‌‌ finishing‌ ‌with‌ ‌the‌ ‌total‌ ‌cost‌ ‌of‌ ‌the‌ ‌items,‌ ‌and‌ ‌the‌ ‌total‌ ‌amounts‌ ‌of‌ ‌sales‌ ‌taxes‌ ‌paid.‌ ‌The‌ ‌rounding‌ ‌rules‌ ‌for‌ ‌sales‌ ‌tax‌ ‌are‌ ‌that‌ ‌for‌ ‌a‌ ‌tax‌‌ rate‌ ‌of‌ ‌n%,‌ ‌a‌ ‌shelf‌ ‌price‌ ‌of‌ ‌p‌ ‌contains‌ ‌(np/100‌ ‌rounded‌ ‌up‌ ‌to‌ ‌the‌ ‌nearest‌ ‌0.05)‌ ‌amount‌ ‌of‌‌ sales‌ ‌tax. ‌ Write‌ ‌an‌ ‌application‌ ‌that‌ ‌prints‌ ‌out‌ ‌the‌ ‌receipt‌ ‌details‌ ‌for‌ ‌these‌ ‌shopping‌ ‌baskets...‌ ‌

Solution

calcTotalPriceInclTaxes(shoppingBasket)

The main function is declared in the index.js file. To use this function it can be imported like in the example below. The function takes a shopping basket as an input and returns a receipt object. The receipt object holds a shopping cart containing all products and their costs including sales taxes. Additionally the overall sales taxes and the total price are also being presented.

The following feature was not mandatory. If the shopping basket accidently contains a product which is not part of the product store, the receipt returns an information text instead of the product cost.

Usage

Setup

It is assumed that git and npm are already installed.

First clone the repo.

git clone https://github.com/Balou9/itemis-cc

Afterwards navigate to the project directory and install required dependencies.

cd itemis-cc && npm i

Run Example

The example is provided in the usage.js file.
Simply run ...

node usage

from the repository directory.

The following example is a copy of the usage file.

const {
  shoppingBasket1,
  shoppingBasket2,
  shoppingBasket3
} = require("./utils/sampleShoppingBasket.js")
const calcTotalPriceInclTaxes = require("./index.js")

const receipt1 = calcTotalPriceInclTaxes(shoppingBasket1)
console.log(receipt1)
// {
//   shoppingCart: {
//     '001': '1 book: 12.49',
//     '002': '1 music CD: 16.49',
//     '003': '1 chocolate bar: 0.85'
//   },
//   'Sales Taxes': 1.5,
//   Total: 29.83
// }

const receipt2 = calcTotalPriceInclTaxes(shoppingBasket2)
console.log(receipt2)
// {
//   shoppingCart: {
//     '001': '1 imported box of chocolates: 10.50',
//     '002': '1 imported bottle of perfume: 54.65'
//   },
//   'Sales Taxes': 7.65,
//   Total: 65.15
// }

const receipt3 = calcTotalPriceInclTaxes(shoppingBasket3)
console.log(receipt3)
// {
//   shoppingCart: {
//     '001': '1 imported bottle of perfume: 32.19',
//     '002': '1 bottle of perfume: 20.89',
//     '003': '1 packet of headache pills: 9.75',
//     '004': '1 imported box of chocolates: 11.85'
//   },
//   'Sales Taxes': 6.7,
//   Total: 74.68
// }

CI Workflow

The ci workflow gets triggered on push commits to the main branch. The ci.yml consists of a test job which runs the test cases.

Test cases

The test cases are defined in the test.js file. The shopping baskets which will serve as test inputs are defined in the sampleShoppingBasket.js file.

Calculates sales taxes and total price

This test case uses the shopping baskets 1 to 3 as provided in the example as an input. It runs the test with the following assertions for each shopping basket.

Tests assertions:

test if the number of products in the shopping cart has the expected value
test if the product price equals the expected value
test if the sales taxes equals the expected value
test if the total price equals the expected value

Does not calculate sales taxes and total price for unavailable products

This test case uses the shopping basket 4 containing one unavailable product as an input.

Tests assertions:

test if the number of unavailable products is as expected
test if the shopping cart is empty
test if the unavailable product information text is as expected
test if the sales taxes equals zero
test if the total is zero

Does calculate for available products, even if the shopping basket contains unavailable products

This test case uses the shopping basket 5 containing one unavailable and one available product as an input.

Tests assertions:

test if the number of unavailable products has the expected value
test if the shopping cart has the expected number of products
test if the unavailable product information text is as expected
test if the price of the available product equals the expected value
test if the sales taxes equals the expected value
test if the total price equals the expected value