LeanCheck

This package extends LeanCheck by providing Listable instances for common types provided by the Haskell Platform.

This package is to LeanCheck what quickcheck-instances is to QuickCheck. The current objective is to include all types supported by quickcheck-instances.

Installing

To install the latest leancheck-instances version from Hackage, just run:

$ cabal update
$ cabal install leancheck-instances

Examples

Importing the library:

> import Test.LeanCheck
> import Test.LeanCheck.Instances

Checking properties of Text:

> import qualified Data.Text as T
> check $ \t -> T.reverse (T.reverse t) == t
+++ OK, passed 200 tests.
> check $ \t -> T.reverse t == t
*** Failed! Falsifiable (after 6 tests):
"a "

Enumerating maps:

> import Data.Map
> list :: [Map Bool Bool]
[ fromList []
, fromList [(False,False)]
, fromList [(False,True)]
, fromList [(True,False)]
, fromList [(True,True)]
, fromList [(False,False),(True,False)]
, fromList [(False,False),(True,True)]
, fromList [(False,True),(True,False)]
, fromList [(False,True),(True,True)]
]
> take 7 $ list :: [Map Int Int]
[ fromList []
, fromList [(0,0)]
, fromList [(0,1)]
, fromList [(1,0)]
, fromList [(0,-1)]
, fromList [(1,1)]
, fromList [(0,0),(1,0)]
]

Further reading / see also

• leancheck-instances’ Haddock Documentation;
• LeanCheck;
• LeanCheck provider for Tasty – $ cabal install tasty-leancheck ;
• LeanCheck provider for test-framework – $ cabal install test-framework-leancheck ;
• LeanCheck provider for Hspec – $ cabal install hspec-leancheck .