Solve 'Chinese Zodiac' kata

Author: borisskert

src/ChineseZodiac.hs

@@ -0,0 +1,11 @@
+module ChineseZodiac where
+
+import Preloaded (animals, elements)
+
+-- https://www.codewars.com/kata/57a73e697cb1f31dd70000d2/train/haskell
+
+chineseZodiac :: Int -> String
+chineseZodiac year = unwords [element, animal]
+  where
+    animal = (animals !!) . (`mod` length animals) . (subtract 1924) $ year
+    element = (elements !!) . (`mod` length elements) . (`div` 2) . (subtract 1924) $ year

src/Preloaded.hs

@@ -41,3 +41,7 @@ data Circle = Circle
   } deriving (Show, Eq)
 
 newtype Player = Player {name :: String} deriving (Show, Eq)
+
+animals = ["Rat", "Ox", "Tiger", "Rabbit", "Dragon", "Snake", "Horse", "Goat", "Monkey", "Rooster", "Dog", "Pig"]
+
+elements = ["Wood", "Fire", "Earth", "Metal", "Water"]

test/ChineseZodiacSpec.hs

@@ -0,0 +1,23 @@
+module ChineseZodiacSpec where
+
+import ChineseZodiac (chineseZodiac)
+import Test.Hspec
+
+spec :: Spec
+spec = do
+  describe "Fixed Tests" $ do
+    it "Works on some basic cases" $ do
+      chineseZodiac 1965 `shouldBe` "Wood Snake"
+      chineseZodiac 1998 `shouldBe` "Earth Tiger"
+      chineseZodiac 2016 `shouldBe` "Fire Monkey"
+      chineseZodiac 1924 `shouldBe` "Wood Rat"
+      chineseZodiac 1968 `shouldBe` "Earth Monkey"
+      chineseZodiac 2162 `shouldBe` "Water Dog"
+      chineseZodiac 6479 `shouldBe` "Earth Goat"
+      chineseZodiac 3050 `shouldBe` "Metal Dog"
+      chineseZodiac 6673 `shouldBe` "Water Rooster"
+      chineseZodiac 6594 `shouldBe` "Wood Tiger"
+      chineseZodiac 9911 `shouldBe` "Metal Goat"
+      chineseZodiac 2323 `shouldBe` "Water Rabbit"
+      chineseZodiac 3448 `shouldBe` "Earth Rat"
+      chineseZodiac 1972 `shouldBe` "Water Rat"