1 files changed, 49 insertions, 0 deletions
diff --git a/third_party/bazel/rules_haskell/examples/vector/tests/Tests/Move.hs b/third_party/bazel/rules_haskell/examples/vector/tests/Tests/Move.hs
new file mode 100644
index 0000000000..60ea8d3346
--- /dev/null
+++ b/third_party/bazel/rules_haskell/examples/vector/tests/Tests/Move.hs
@@ -0,0 +1,49 @@
+module Tests.Move (tests) where
+
+import Test.QuickCheck
+import Test.Framework.Providers.QuickCheck2
+import Test.QuickCheck.Property (Property(..))
+
+import Utilities ()
+
+import Control.Monad (replicateM)
+import Control.Monad.ST (runST)
+import Data.List (sort,permutations)
+
+import qualified Data.Vector.Generic as G
+import qualified Data.Vector.Generic.Mutable as M
+
+import qualified Data.Vector as V
+import qualified Data.Vector.Primitive as P
+import qualified Data.Vector.Storable as S
+import qualified Data.Vector.Unboxed as U
+
+basicMove :: G.Vector v a => v a -> Int -> Int -> Int -> v a
+basicMove v dstOff srcOff len
+  | len > 0 = G.modify (\ mv -> G.copy (M.slice dstOff len mv) (G.slice srcOff len v)) v
+  | otherwise = v
+
+testMove :: (G.Vector v a, Show (v a), Eq (v a)) => v a -> Property
+testMove v = G.length v > 0 ==> (MkProperty $ do
+  dstOff <- choose (0, G.length v - 1)
+  srcOff <- choose (0, G.length v - 1)
+  len <- choose (1, G.length v - max dstOff srcOff)
+  expected <- return $ basicMove v dstOff srcOff len
+  actual <- return $  G.modify (\ mv -> M.move (M.slice dstOff len mv) (M.slice srcOff len mv)) v
+  unProperty $ counterexample ("Move: " ++ show (v, dstOff, srcOff, len)) (expected == actual))
+
+checkPermutations :: Int -> Bool
+checkPermutations n = runST $ do
+    vec <- U.thaw (U.fromList [1..n])
+    res <- replicateM (product [1..n]) $ M.nextPermutation vec >> U.freeze vec >>= return . U.toList
+    return $! ([1..n] : res) == sort (permutations [1..n]) ++ [[n,n-1..1]]
+
+testPermutations :: Bool
+testPermutations = all checkPermutations [1..7]
+
+tests =
+    [testProperty "Data.Vector.Mutable (Move)" (testMove :: V.Vector Int -> Property),
+     testProperty "Data.Vector.Primitive.Mutable (Move)" (testMove :: P.Vector Int -> Property),
+     testProperty "Data.Vector.Unboxed.Mutable (Move)" (testMove :: U.Vector Int -> Property),
+     testProperty "Data.Vector.Storable.Mutable (Move)" (testMove :: S.Vector Int -> Property),
+     testProperty "Data.Vector.Generic.Mutable (nextPermutation)" testPermutations]