{-# LANGUAGE RankNTypes #-} {-# OPTIONS_GHC -Wno-unrecognised-pragmas #-} {-# HLINT ignore "Monad law, left identity" #-} {-# HLINT ignore "Monad law, right identity" #-} {-# HLINT ignore "Use <\$>" #-} module Monad ( test ) where import Control.Monad (ap, (>=>)) import Gen import Test.Tasty import Test.Tasty.Hedgehog test :: (Monad m, Arg a, Arg b, Eq (g a), Eq (g b), Eq (g c), Show a, Show b, Show (g a), Show (g b), Show (g c), Vary a, Vary b, Functor f) => GenM m -> GenTerm a -> GenTerm b -> GenTerm c -> GenTerm (f ()) -> Run f g m -> [TestTree] test m a b c s (Run run) = [ testProperty "return is the left-identity of >>=" . forall (s :. a :. fn (m b) :. Nil) \$ \ s a k -> run ((return a >>= k) <\$ s) === run (k a <\$ s) , testProperty "return is the right-identity of >>=" . forall (s :. m a :. Nil) \$ \ s m -> run ((m >>= return) <\$ s) === run (m <\$ s) , testProperty ">>= is associative" . forall (s :. m a :. fn (m b) :. fn (m c) :. Nil) \$ \ s m k h -> run ((m >>= (k >=> h)) <\$ s) === run (((m >>= k) >>= h) <\$ s) , testProperty "return = pure" . forall (s :. a :. Nil) \$ \ s a -> run (return a <\$ s) === run (pure a <\$ s) , testProperty "ap = (<*>)" . forall (s :. fn b :. m a :. Nil) \$ \ s f m -> run ((pure f `ap` m) <\$ s) === run ((pure f <*> m) <\$ s) ]