pinak1180 / checkout-kata-ruby

A physical store which sells 3 products

Checkout Kata Ruby

• Instructions
• How to use this solution

Instructions

A physical store which sells 3 products:

Code         | Name                |  Price
-------------------------------------------------
VOUCHER      | Cabify Voucher      |   5.00€
TSHIRT       | Cabify T-Shirt      |  20.00€
MUG          | Cafify Coffee Mug   |   7.50€

Various departments have insisted on the following discounts:

• The marketing department believes in 2-for-1 promotions (buy two of the same product, get one free), and would like for there to be a 2-for-1 special on VOUCHER items.

• The CFO insists that the best way to increase sales is with discounts on bulk purchases (buying x or more of a product, the price of that product is reduced), and demands that if you buy 3 or more TSHIRT items, the price per unit should be 19.00€.

The checkout process allows for items to be scanned in any order, and should return the total amount to be paid. The interface for the checkout process looks like this (ruby):

co = Checkout.new(pricing_rules)
co.scan("VOUCHER")
co.scan("VOUCHER")
co.scan("TSHIRT")
price = co.total

Using ruby (>= 2.0), implement a checkout process that fulfills the requirements.

Examples:

Items: VOUCHER, TSHIRT, MUG
Total: 32.50€

Items: VOUCHER, TSHIRT, VOUCHER
Total: 25.00€

Items: TSHIRT, TSHIRT, TSHIRT, VOUCHER, TSHIRT
Total: 81.00€

Items: VOUCHER, TSHIRT, VOUCHER, VOUCHER, MUG, TSHIRT, TSHIRT
Total: 74.50€

How to use this solution

This implementation was developed using Ruby 2.3.0

You also need Bundler for dependency management. Remember to run bundle install

To run the application in the shell use ruby checkout_shell.rb [Input]. For example: ruby checkout_shell.rb "VOUCHER" "TSHIRT" "MUG"

To run all tests use bundle exec rake test

To autorun tests while you develop run bundle exec guard