Add 'users/glittershark/xanthous/' from commit '53b56744f4'

git-subtree-dir: users/glittershark/xanthous
git-subtree-mainline: 91f53f02d8
git-subtree-split: 53b56744f4

users/glittershark/xanthous/test/Xanthous/DataSpec.hs

@@ -0,0 +1,98 @@
+--------------------------------------------------------------------------------
+module Xanthous.DataSpec (main, test) where
+--------------------------------------------------------------------------------
+import Test.Prelude hiding (Right, Left, Down, toList, all)
+import Data.Group
+import Data.Foldable (toList, all)
+--------------------------------------------------------------------------------
+import Xanthous.Data
+--------------------------------------------------------------------------------
+
+main :: IO ()
+main = defaultMain test
+
+test :: TestTree
+test = testGroup "Xanthous.Data"
+  [ testGroup "Position"
+    [ testBatch $ monoid @Position mempty
+    , testProperty "group laws" $ \(pos :: Position) ->
+        pos <> invert pos == mempty && invert pos <> pos == mempty
+    , testGroup "stepTowards laws"
+      [ testProperty "takes only one step" $ \src tgt ->
+          src /= tgt ==>
+            isUnit (src `diffPositions` (src `stepTowards` tgt))
+      -- , testProperty "moves in the right direction" $ \src tgt ->
+      --     stepTowards src tgt == move (directionOf src tgt) src
+      ]
+    , testProperty "directionOf laws" $ \pos dir ->
+        directionOf pos (move dir pos) == dir
+    , testProperty "diffPositions is add inverse" $ \(pos₁ :: Position) pos₂ ->
+        diffPositions pos₁ pos₂ == addPositions pos₁ (invert pos₂)
+    , testGroup "isUnit"
+      [ testProperty "double direction is never unit" $ \dir ->
+          not . isUnit $ move dir (asPosition dir)
+      , testCase "examples" $ do
+          isUnit (Position @Int 1 1) @? "not . isUnit $ Position 1 1"
+          isUnit (Position @Int 0 (-1)) @? "not . isUnit $ Position 0 (-1)"
+          (not . isUnit) (Position @Int 1 13) @? "isUnit $ Position 1 13"
+      ]
+    ]
+
+  , testGroup "Direction"
+    [ testProperty "opposite is involutive" $ \(dir :: Direction) ->
+        opposite (opposite dir) == dir
+    , testProperty "opposite provides inverse" $ \dir ->
+        invert (asPosition dir) === asPosition (opposite dir)
+    , testProperty "asPosition isUnit" $ \dir ->
+        dir /= Here ==> isUnit (asPosition dir)
+    , testGroup "Move"
+      [ testCase "Up"        $ move Up mempty        @?= Position @Int 0 (-1)
+      , testCase "Down"      $ move Down mempty      @?= Position @Int 0 1
+      , testCase "Left"      $ move Left mempty      @?= Position @Int (-1) 0
+      , testCase "Right"     $ move Right mempty     @?= Position @Int 1 0
+      , testCase "UpLeft"    $ move UpLeft mempty    @?= Position @Int (-1) (-1)
+      , testCase "UpRight"   $ move UpRight mempty   @?= Position @Int 1 (-1)
+      , testCase "DownLeft"  $ move DownLeft mempty  @?= Position @Int (-1) 1
+      , testCase "DownRight" $ move DownRight mempty @?= Position @Int 1 1
+      ]
+    ]
+
+  , testGroup "Corner"
+    [ testGroup "instance Opposite"
+      [ testProperty "involutive" $ \(corner :: Corner) ->
+          opposite (opposite corner) === corner
+      ]
+    ]
+
+  , testGroup "Edge"
+    [ testGroup "instance Opposite"
+      [ testProperty "involutive" $ \(edge :: Edge) ->
+          opposite (opposite edge) === edge
+      ]
+    ]
+
+  , testGroup "Box"
+    [ testGroup "boxIntersects"
+      [ testProperty "True" $ \dims ->
+          boxIntersects (Box @Word (V2 1 1) (V2 2 2))
+                        (Box (V2 2 2) dims)
+      , testProperty "False" $ \dims ->
+          not $ boxIntersects (Box @Word (V2 1 1) (V2 2 2))
+                            (Box (V2 4 2) dims)
+      ]
+    ]
+
+  , testGroup "Neighbors"
+    [ testGroup "rotations"
+      [ testProperty "always has the same members"
+        $ \(neighs :: Neighbors Int) ->
+          all (\ns -> sort (toList ns) == sort (toList neighs))
+          $ rotations neighs
+      , testProperty "all rotations have the same rotations"
+        $ \(neighs :: Neighbors Int) ->
+          let rots = rotations neighs
+          in all (\ns -> sort (toList $ rotations ns) == sort (toList rots))
+             rots
+      ]
+    ]
+  ]