Tech Test - Shopping Basket Discount Task

A company issues two types of voucher for customers to gain discounts on shopping baskets.

Gift Voucher

• Can be redeemed against the value of a basket.
• Multiple gift vouchers can be applied to a basket.

Offer vouchers

• Have a threshold that needs to be matched or exceeded before a discount can be applied e.g. £5.00 off of baskets totalling £50
• Only a single offer voucher can be applied to a basket.
• Maybe applicable to only a subset of products.

Functionality / Business Logic

• Offer and Gift vouchers can be used in conjunction.
• If a customer applies an offer voucher to a basket that will not satisfy the threshold or a customer removes item/changes an items quantity resulting in a voucher not being a message will need to be displayed to the customer.
• Gift vouchers can only be redeemed against non gift voucher products and purchase of gift vouchers do no contribute to discountable basket total.

Task

• You need not create a UI for this application.
• Write an application that represents a basket and has the ability to handle the following scenarios:

Basket 1
1 Hat @ £10.50
1 Jumper @ £54.65
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1 x £5.00 Gift Voucher XXX-XXX applied
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Total: £60.15
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Basket 2
1 Hat @ £25.00
1 Jumper @ £26.00
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1 x £5.00 off Head Gear in baskets over £50.00 Offer Voucher YYY-YYY applied
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Total: £51.00
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Message: “There are no products in your basket applicable to voucher Voucher YYY-YYY .”

Basket 3
1 Hat @ £25.00
1 Jumper @ £26.00
1 Head Light (Head Gear Category of Product) @ £3.50
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1 x £5.00 off Head Gear in baskets over £50.00 Offer Voucher YYY-YYY applied
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Total: £51.00
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Basket 4
1 Hat @ £25.00
1 Jumper @ £26.00
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1 x £5.00 Gift Voucher XXX-XXX applied
1 x £5.00 off baskets over £50.00 Offer Voucher YYY-YYY applied
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Total: £41.00
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Basket 5
1 Hat @ £25.00
1 £30 Gift Voucher @ £30.00
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1 x £5.00 off baskets over £50.00 Offer Voucher YYY-YYY applied
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Total: £55.00
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Message: “You have not reached the spend threshold for voucher YYY-YYY. Spend another £25.01 to receive £5.00 discount from your basket total.”

Solution

This repo contains code for the tech test above, there are things I would change with more time and refactor down more. Have tried to add some design patterns here decorator, factory, strategy, specification ...

• Have created a shopping basket that handles different voucher types and has the ability to easily create new voucher types and have them applied to the shopping cart. This is done through a VoucherFactory.

• Vouchers have spefication property to decide if they can be applied to a cart and a strategy property which determines how they are applied to the cart.

• Have implemented the 5 basket examples from the tech test.

• Gym.Tests has various unit tests and the BasketScenarioTests contains a test for each of the 5 basket examples (covering a lot of the logic for each basket example)

• Gym.Console runs the 5 basket examples as well and outputs a display property from the basket which shows the state of the basket.

Project	Description
Gym.Ecommerce	Main functional logic
Gym.Tests	Some unit tests
Gym.Console	Console app that outputs 5 baskets from tech test

Have added FluentAssertions for the unit tests