hspec-leancheck: LeanCheck support for Hspec

LeanCheck support for the Hspec test framework.

Installing

$ cabal install hspec-leancheck

Example

Here’s how your spec.hs might look like:

import Test.Hspec
import Test.Hspec.LeanCheck as LC

import Data.List (sort)

main :: IO ()
main = hspec spec

spec :: Spec
spec = do
  describe "sort" $ do
    it "is idempotent" $
      LC.property $ \xs -> sort (sort xs :: [Int]) == sort xs
    it "is identity" $ -- not really
      LC.property $ \xs -> sort (xs :: [Int]) == xs

And here is the output for the above program:

$ ./eg/minimal

sort
  is idempotent
  is identity FAILED [1]

Failures:

  eg/minimal.hs:17:5: 
  1) sort is identity
       [1,0]

  To rerun use: --match "/sort/is identity/"

Randomized with seed 44182769

Finished in 0.0008 seconds
2 examples, 1 failure

Options

Use propertyWith to configure the number of tests.

Further reading

• hspec-leancheck’s Haddock documentation;
• LeanCheck’s Haddock documentation;
• Hspec’s Haddock documentation;
• LeanCheck’s README;
• Hspec’s README;
• Tutorial on property-based testing with LeanCheck.