-- to suppress WARNING in "Distribution.Compat.Prelude.Internal"
{-# OPTIONS_GHC -fno-warn-deprecations #-}
module UnitTests.Distribution.Utils.NubList
( tests
) where
import Prelude ()
import Distribution.Compat.Prelude.Internal
import Distribution.Utils.NubList
import Test.Tasty
import Test.Tasty.HUnit
import Test.Tasty.QuickCheck
tests :: [TestTree]
tests =
[ testCase "NubList retains ordering example" testOrdering
, testCase "NubList removes duplicates example" testDeDupe
, testProperty "NubList retains ordering" prop_Ordering
, testProperty "NubList removes duplicates" prop_DeDupe
, testProperty "fromNubList . toNubList = nub" prop_Nub
, testProperty "Monoid NubList Identity" prop_Identity
, testProperty "Monoid NubList Associativity" prop_Associativity
-- NubListR
, testProperty "NubListR removes duplicates from the right" prop_DeDupeR
]
someIntList :: [Int]
-- This list must not have duplicate entries.
someIntList = [ 1, 3, 4, 2, 0, 7, 6, 5, 9, -1 ]
testOrdering :: Assertion
testOrdering =
assertBool "Maintains element ordering:" $
fromNubList (toNubList someIntList) == someIntList
testDeDupe :: Assertion
testDeDupe =
assertBool "De-duplicates a list:" $
fromNubList (toNubList (someIntList ++ someIntList)) == someIntList
-- ---------------------------------------------------------------------------
-- QuickCheck properties for NubList
prop_Ordering :: [Int] -> Property
prop_Ordering xs =
mempty <> toNubList xs' === toNubList xs' <> mempty
where
xs' = nub xs
prop_DeDupe :: [Int] -> Property
prop_DeDupe xs =
fromNubList (toNubList (xs' ++ xs)) === xs' -- Note, we append primeless xs
where
xs' = nub xs
prop_DeDupeR :: [Int] -> Property
prop_DeDupeR xs =
fromNubListR (toNubListR (xs ++ xs')) === xs' -- Note, we prepend primeless xs
where
xs' = nub xs
prop_Nub :: [Int] -> Property
prop_Nub xs = rhs === lhs
where
rhs = fromNubList (toNubList xs)
lhs = nub xs
prop_Identity :: [Int] -> Bool
prop_Identity xs =
mempty `mappend` toNubList xs == toNubList xs `mappend` mempty
prop_Associativity :: [Int] -> [Int] -> [Int] -> Bool
prop_Associativity xs ys zs =
(toNubList xs `mappend` toNubList ys) `mappend` toNubList zs
== toNubList xs `mappend` (toNubList ys `mappend` toNubList zs)