module Data.Mapping.MapWithDefaultSpec where import Data.Mapping import Data.Mapping.MapWithDefault import Test.Hspec spec :: Spec spec = do describe "MapWithDefault" $ do let m = fromList (1 :: Int) [('a',1), ('b',2), ('c',3)] let n = fromList (2 :: Int) [('b',1), ('c',1), ('d',3)] it "merges correctly" $ do merge (+) m n `shouldBe` fromList 3 [('c',4), ('d',4)]