Success is most often achieved by those who don't know that failure is inevitable.
--Coco Chanel
polysemy-check is a little package that integrates
polysemy with
QuickCheck. It allows you to
prove the equivalence of effects (see prepropLaw), the equivalence of
interpreters (prepropEquivalent), and that two effects don't affect one
another (prepropCommutative). These three things are about the only problems
you could possibly run into with Polysemy --- and now you won't.
In addition polysemy-check provides lots of machinery to help avoid
boilerplate, such as free Arbitrary instances for effects.
polysemy-check requires a Show and GenericK instance for every effect
you'd like to run tests over.
{-# LANGUAGE TemplateHaskell #-}
import Polysemy
import Polysemy.Check
data Stack m a where
Push :: Int -> Stack m ()
Pop :: Stack m (Maybe Int)
Size :: Stack m Int
deriving instance Show (Stack m a)
makeSem ''Stack
deriveGenericK ''StackCheck the test suite.