Test suite build failure in stackage nightly

test/main.hs:257:31:
    Overlapping instances for Arbitrary (Map Int Char)
      arising from a use of ‘dictionaryProps’
    Matching instances:
      instance [safe] (Ord k, Arbitrary k, Arbitrary v) =>
                      Arbitrary (Map k v)
        -- Defined in ‘Test.QuickCheck.Arbitrary’
      instance Arbitrary (Map Int Char) -- Defined at test/main.hs:417:10
    In the second argument of ‘($)’, namely
      ‘dictionaryProps (undefined :: Map Int Char)’
    In a stmt of a 'do' block:
      describe "Data.Map" $ dictionaryProps (undefined :: Map Int Char)
    In the second argument of ‘($)’, namely
      ‘do { describe "Data.Map"
            $ dictionaryProps (undefined :: Map Int Char);
            describe "Data.HashMap"
            $ dictionaryProps (undefined :: HashMap Int Char);
            describe "assoc list"
            $ dictionaryProps (undefined :: [(Int, Char)]) }’

test/main.hs:264:31:
    Overlapping instances for Arbitrary (Set Int)
      arising from a use of ‘mapProps’
    Matching instances:
      instance [safe] (Ord a, Arbitrary a) => Arbitrary (Set a)
        -- Defined in ‘Test.QuickCheck.Arbitrary’
      instance Arbitrary (Set Int) -- Defined at test/main.hs:425:10
    In the second argument of ‘($)’, namely
      ‘mapProps Set.map setFromList (undefined :: Set Int) (+ 1) (+ 2)’
    In a stmt of a 'do' block:
      describe "Data.Set"
      $ mapProps Set.map setFromList (undefined :: Set Int) (+ 1) (+ 2)
    In the second argument of ‘($)’, namely
      ‘do { describe "list"
            $ mapProps fmap pack (undefined :: [Int]) (+ 1) (+ 2);
            describe "Data.Vector"
            $ mapProps fmap pack (undefined :: Vector Int) (+ 1) (+ 2);
            describe "Data.Vector.Unboxed"
            $ mapProps omap pack (undefined :: UVector Int) (+ 1) (+ 2);
            describe "Data.Set"
            $ mapProps Set.map setFromList (undefined :: Set Int) (+ 1) (+ 2);
            .... }’

test/main.hs:270:36:
    Overlapping instances for Arbitrary (Seq Int)
      arising from a use of ‘mapProps’
    Matching instances:
      instance [safe] Arbitrary a => Arbitrary (Seq a)
        -- Defined in ‘Test.QuickCheck.Arbitrary’
      instance Arbitrary (Seq Int) -- Defined at test/main.hs:437:10
    In the second argument of ‘($)’, namely
      ‘mapProps fmap pack (undefined :: Seq Int) succ succ’
    In a stmt of a 'do' block:
      describe "Data.Sequence"
      $ mapProps fmap pack (undefined :: Seq Int) succ succ
    In the second argument of ‘($)’, namely
      ‘do { describe "list"
            $ mapProps fmap pack (undefined :: [Int]) (+ 1) (+ 2);
            describe "Data.Vector"
            $ mapProps fmap pack (undefined :: Vector Int) (+ 1) (+ 2);
            describe "Data.Vector.Unboxed"
            $ mapProps omap pack (undefined :: UVector Int) (+ 1) (+ 2);
            describe "Data.Set"
            $ mapProps Set.map setFromList (undefined :: Set Int) (+ 1) (+ 2);
            .... }’
snoyberg / classy-prelude

Test suite build failure in stackage nightly #117
