20 lines
727 B
Haskell
20 lines
727 B
Haskell
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module Spec where
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import Test.Hspec
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import Test.QuickCheck
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import Control.Exception (evaluate)
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main :: IO ()
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main = hspec $ do
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describe "Prelude.head" $ do
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it "returns the first element of a list" $ do
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head [23 ..] `shouldBe` (23 :: Integer)
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it "returns the first element of an arbitrary list" $
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property $ \x xs -> head (x:xs) == (x :: Integer)
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it "throws an exception if used with an empty list" $ do
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evaluate (head []) `shouldThrow` anyException
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