Sales Taxes

The default rake task runs the tests.

Problem

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…

• Input 1: 1 book at 12.49 1 music CD at 14.99 1 chocolate bar at 0.85

• Input 2: 1 imported box of chocolates at 10.00 1 imported bottle of perfume at 47.50

• Input 3: 1 imported bottle of perfume at 27.99 1 bottle of perfume at 18.99 1 packet of headache pills at 9.75 1 box of imported chocolates at 11.25

• Output 1: 1 book : 12.49 1 music CD: 16.49 1 chocolate bar: 0.85 Sales Taxes: 1.50 Total: 29.83

• Output 2: 1 imported box of chocolates: 10.50 1 imported bottle of perfume: 54.65 Sales Taxes: 7.65 Total: 65.15

• Output 3: 1 imported bottle of perfume: 32.19 1 bottle of perfume: 20.89 1 packet of headache pills: 9.75 1 imported box of chocolates: 11.85 Sales Taxes: 6.70 Total: 74.68

Assumptions

• Items that are exempt from tax are defined in a constant. In real world scenarios those would likely be the result of a database query or an API call.

• All items have a quantity of 1. This seems to be ok, as the provided test cases also assume this. If this requirement changes, the code is easily adaptable.

• I copied the asserted output as is, except in the following two cases:

  • changed book : 12.49 to book: 12.49, for consistency with the other output
  • changed 1 imported box of chocolates to 1 box of imported chocolates, to be consistent with the corresponding input