Describe what you see when you walk over items

Every step the character takes, describe the entities at that position
excluding the character.

test/Xanthous/Util/InflectionSpec.hs

@@ -0,0 +1,18 @@
+module Xanthous.Util.InflectionSpec (main, test) where
+
+import Test.Prelude
+import Xanthous.Util.Inflection
+
+main :: IO ()
+main = defaultMain test
+
+test :: TestTree
+test = testGroup "Xanthous.Util.Inflection"
+  [ testGroup "toSentence"
+    [ testCase "empty"  $ toSentence [] @?= ""
+    , testCase "single" $ toSentence ["x"] @?= "x"
+    , testCase "two"    $ toSentence ["x", "y"] @?= "x and y"
+    , testCase "three"  $ toSentence ["x", "y", "z"] @?= "x, y, and z"
+    , testCase "four"   $ toSentence ["x", "y", "z", "w"] @?= "x, y, z, and w"
+    ]
+  ]