Test.StateMachine.Utils

This module exports some QuickCheck utility functions. Some of these should perhaps be upstreamed.

Documentation

liftProperty :: Monad m => Property -> PropertyM m ()

Lifts a plain property into a monadic property.

whenFailM :: Monad m => IO () -> Property -> PropertyM m ()

Lifts whenFail to PropertyM.

anyP :: (a -> Property) -> [a] -> Property

Lifts any to properties.

suchThatEither :: forall a. Gen a -> (a -> Bool) -> Gen (Either [a] a)

collects :: Show a => [a] -> Property -> Property

data Shrunk a

More permissive notion of shrinking where a value can shrink to itself

For example

shrink  3 == [0, 2] -- standard QuickCheck shrink
shrinkS 3 == [Shrunk True 0, Shrunk True 2, Shrunk False 3]

This is primarily useful when shrinking composite structures: the combinators here keep track of whether something was shrunk somewhere in the structure. For example, we have

   shrinkListS (shrinkPairS shrinkS shrinkS) [(1,3),(2,4)]
== [ Shrunk True  []             -- removed all elements of the list
   , Shrunk True  [(2,4)]        -- removed the first
   , Shrunk True  [(1,3)]        -- removed the second
   , Shrunk True  [(0,3),(2,4)]  -- shrinking the '1'
   , Shrunk True  [(1,0),(2,4)]  -- shrinking the '3'
   , Shrunk True  [(1,2),(2,4)]  -- ..
   , Shrunk True  [(1,3),(0,4)]  -- shrinking the '2'
   , Shrunk True  [(1,3),(1,4)]  -- ..
   , Shrunk True  [(1,3),(2,0)]  -- shrinking the '4'
   , Shrunk True  [(1,3),(2,2)]  -- ..
   , Shrunk True  [(1,3),(2,3)]  -- ..
   , Shrunk False [(1,3),(2,4)]  -- the original unchanged list
   ]

Constructors

Shrunk

Fields

• wasShrunk :: Bool
• shrunk :: a

Instances

Functor Shrunk

Defined in Test.StateMachine.Utils

Methods

fmap :: (a -> b) -> Shrunk a -> Shrunk b

(<$) :: a -> Shrunk b -> Shrunk a

Eq a => Eq (Shrunk a)

Defined in Test.StateMachine.Utils

Methods

(==) :: Shrunk a -> Shrunk a -> Bool

(/=) :: Shrunk a -> Shrunk a -> Bool

Show a => Show (Shrunk a)

Defined in Test.StateMachine.Utils

Methods

showsPrec :: Int -> Shrunk a -> ShowS

show :: Shrunk a -> String

showList :: [Shrunk a] -> ShowS

shrinkS :: Arbitrary a => a -> [Shrunk a]

shrinkListS :: forall a. (a -> [Shrunk a]) -> [a] -> [Shrunk [a]]

shrinkListS' :: [a] -> [Shrunk [a]]

Shrink list without shrinking elements.

shrinkListS'' :: forall a. (a -> [Shrunk a]) -> [a] -> [Shrunk [a]]

Shrink list by only shrinking elements.

shrinkPairS :: (a -> [Shrunk a]) -> (b -> [Shrunk b]) -> (a, b) -> [Shrunk (a, b)]

shrinkPairS' :: (a -> [Shrunk a]) -> (a, a) -> [Shrunk (a, a)]

pickOneReturnRest :: [a] -> [(a, [a])]

pickOneReturnRest2 :: ([a], [a]) -> [(a, ([a], [a]))]

pickOneReturnRestL :: [[a]] -> [(a, [[a]])]

mkModel :: StateMachine model cmd m resp -> History cmd resp -> model Concrete