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/Data/EntityMapSpec.hs

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+{-# LANGUAGE ApplicativeDo #-}
+--------------------------------------------------------------------------------
+module Xanthous.Data.EntityMapSpec where
+--------------------------------------------------------------------------------
+import           Test.Prelude
+--------------------------------------------------------------------------------
+import qualified Data.Aeson as JSON
+--------------------------------------------------------------------------------
+import           Xanthous.Data.EntityMap
+import           Xanthous.Data (Positioned(..))
+--------------------------------------------------------------------------------
+
+main :: IO ()
+main = defaultMain test
+
+test :: TestTree
+test = localOption (QuickCheckTests 20)
+  $ testGroup "Xanthous.Data.EntityMap"
+  [ testBatch $ monoid @(EntityMap Int) mempty
+  , testGroup "Deduplicate"
+    [ testGroup "Semigroup laws"
+      [ testProperty "associative" $ \(a :: Deduplicate (EntityMap Int)) b c ->
+          a <> (b <> c) === (a <> b) <> c
+      ]
+    ]
+  , testGroup "Eq laws"
+    [ testProperty "reflexivity" $ \(em :: EntityMap Int) ->
+        em == em
+    , testProperty "symmetric" $ \(em₁ :: EntityMap Int) em₂ ->
+        (em₁ == em₂) == (em₂ == em₁)
+    , testProperty "transitive" $ \(em₁ :: EntityMap Int) em₂ em₃ ->
+        if (em₁ == em₂ && em₂ == em₃)
+        then (em₁ == em₃)
+        else True
+    ]
+  , testGroup "JSON encoding/decoding"
+    [ testProperty "round-trips" $ \(em :: EntityMap Int) ->
+        let em' = JSON.decode (JSON.encode em)
+        in counterexample (show (em' ^? _Just . lastID, em ^. lastID
+                                , em' ^? _Just . byID == em ^. byID . re _Just
+                                , em' ^? _Just . byPosition == em ^. byPosition . re _Just
+                                , em' ^? _Just . _EntityMap == em ^. _EntityMap . re _Just
+                                ))
+           $ em' === Just em
+    , testProperty "Preserves IDs" $ \(em :: EntityMap Int) ->
+        let Just em' = JSON.decode $ JSON.encode em
+        in toEIDsAndPositioned em' === toEIDsAndPositioned em
+    ]
+
+  , localOption (QuickCheckTests 50)
+  $ testGroup "atPosition"
+    [ testProperty "setget" $ \pos (em :: EntityMap Int) es ->
+        view (atPosition pos) (set (atPosition pos) es em) === es
+    , testProperty "getset" $ \pos (em :: EntityMap Int) ->
+        set (atPosition pos) (view (atPosition pos) em) em === em
+    , testProperty "setset" $ \pos (em :: EntityMap Int) es ->
+        (set (atPosition pos) es . set (atPosition pos) es) em
+        ===
+        set (atPosition pos) es em
+      -- testProperty "lens laws" $ \pos -> isLens $ atPosition @Int pos
+    , testProperty "preserves IDs" $ \(em :: EntityMap Int) e1 e2 p ->
+        let (eid, em') = insertAtReturningID p e1 em
+            em'' = em' & atPosition p %~ (e2 <|)
+        in
+          counterexample ("em': " <> show em')
+          . counterexample ("em'': " <> show em'')
+          $ em'' ^. at eid === Just (Positioned p e1)
+    ]
+  ]