PHPUnit example

Task description

You have products database:

Product code	Name	Price
FR1	Fruit Tea	$3.11
SR1	Strawberries	$5.00
CF1	Coffee	$11.23

1. CEO wants that if you buy at least one tea, next should be free.
2. CTO wants low prices, so that, if you buy 3 or more strawberries price should drop to $4.50.

Your code should be flexible, because CTO and CEO often changes the rules.

The service should look like this:

$ch = new Checkout($pricing_rules);
$co->scan($item1);
$co->scan($item2);
$price = $ch->total();

Implement a checkout system that fulfils these requirements.

Test data

Basket: FR1,SR1,FR1,FR1,CF1
Total price expected: $22.45

Basket: FR1,FR1
Total price expected: $3.11

Basket: SR1,SR1,FR1,SR1
Total price expected: $16.61