Gilded Rose Functional is an introduction to functional programming and a resource for practicing functional refactoring and design.
If you are unfamiliar with the Gilded Rose, read the Gilded Rose Requirements first. You may also learn more about the Gilded Rose from Gilded Rose Refactoring Kata. If you are unfamiliar with functional programming, read through Functional Programming Fundamentals.
npm install --global yarnyarnyarn lintyarn test======================================
Gilded Rose Requirements Specification
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Hi and welcome to team Gilded Rose. As you know, we are a small inn with a prime location in a
prominent city ran by a friendly innkeeper named Allison. We also buy and sell only the finest goods.
Unfortunately, our goods are constantly degrading in quality as they approach their sell by date. We
have a system in place that updates our inventory for us. It was developed by a no-nonsense type named
Leeroy, who has moved on to new adventures. Your task is to add the new feature to our system so that
we can begin selling a new category of items. First an introduction to our system:
- All items have a SellIn value which denotes the number of days we have to sell the item
- All items have a Quality value which denotes how valuable the item is
- At the end of each day our system lowers both values for every item
Pretty simple, right? Well this is where it gets interesting:
- Once the sell by date has passed, Quality degrades twice as fast
- The Quality of an item is never negative
- "Aged Brie" actually increases in Quality the older it gets
- The Quality of an item is never more than 50
- "Sulfuras", being a legendary item, never has to be sold or decreases in Quality
- "Backstage passes", like aged brie, increases in Quality as its SellIn value approaches;
Quality increases by 2 when there are 10 days or less and by 3 when there are 5 days or less but
Quality drops to 0 after the concert
We have recently signed a supplier of conjured items. This requires an update to our system:
- "Conjured" items degrade in Quality twice as fast as normal items
Feel free to make any changes to the UpdateQuality method and add any new code as long as everything
still works correctly. However, do not alter the Item class or Items property as those belong to the
goblin in the corner who will insta-rage and one-shot you as he doesn't believe in shared code
ownership (you can make the UpdateQuality method and Items property static if you like, we'll cover
for you).
Just for clarification, an item can never have its Quality increase above 50, however "Sulfuras" is a
legendary item and as such its Quality is 80 and it never alters.
- Create a web interface for the Gilded Rose
- Create a testing and refactoring guide to the Gilded Rose
- Integrate functional TypeScript concepts.