tvl-depot/test/Xanthous/UtilSpec.hs

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module Xanthous.UtilSpec (main, test) where
import Test.Prelude
import Xanthous.Util
main :: IO ()
main = defaultMain test
test :: TestTree
test = testGroup "Xanthous.Util"
[ testGroup "smallestNotIn"
[ testCase "examples" $ do
smallestNotIn [7 :: Word, 3, 7] @?= 0
smallestNotIn [7 :: Word, 0, 1, 3, 7] @?= 2
, testProperty "returns an element not in the list" $ \(xs :: [Word]) ->
smallestNotIn xs `notElem` xs
, testProperty "pred return is in the list" $ \(xs :: [Word]) ->
let res = smallestNotIn xs
in res /= 0 ==> pred res `elem` xs
, testProperty "ignores order" $ \(xs :: [Word]) ->
forAll (shuffle xs) $ \shuffledXs ->
smallestNotIn xs === smallestNotIn shuffledXs
]
]