leancheck-extras (empty) → 0

raw patch · 2 files changed

+92/−0 lines, 2 filesdep +basedep +leancheck

Dependencies added: base, leancheck

Files

• leancheck-extras.cabal +19/−0
• src/Test/LeanCheck/Extras.hs +73/−0

@@ -0,0 +1,19 @@+cabal-version: 3.12+name: leancheck-extras+synopsis: extra features for leancheck+version: 0+category: Testing+build-type: Simple         +license: BSD-3-Clause++tested-with: GHC==9.14, GHC==9.12, GHC==9.10, GHC==9.8, GHC==9.6++source-repository head+  type: git+  location: https://git.imn.htwk-leipzig.de/waldmann/leancheck-extras.git+                              +library+  hs-source-dirs: src+  exposed-modules: Test.LeanCheck.Extras+  build-depends: base >= 4 && < 5, leancheck >= 1 && < 1.1+  default-language: Haskell2010

@@ -0,0 +1,73 @@+{-# language TypeApplications, ExplicitForAll, RankNTypes, GADTs #-}++module Test.LeanCheck.Extras+  (Instances(..),Prop(..),Test(..),And(..))+where++import Test.LeanCheck+import Test.LeanCheck.Core (resultiers)+import qualified Data.List as L++{- | Extra combinators for leancheck, a property-based testing library.++example usage:++> > prop :: forall a . Eq a => [a] -> Bool+> > prop xs = xs == reverse xs++> > p = And+> >   [ Test $ Prop "reverse @Unit" $ Instances 20 $ prop @())+> >   , Test $ Prop "reverse @Bool" $ Instances 30 $ prop @Bool)+> >   ]++> > check p+> *** Failed! Falsifiable (after 27 tests):+> reverse @Bool [False,True]++-}++prop :: forall a . Eq a => [a] -> Bool+prop xs = xs == reverse xs++p = And+  [ Test $ Prop "reverse @Unit" $ Instances 20 $ prop @()+  , Test $ Prop "reverse @Bool" $ Instances 30 $ prop @Bool+  ]+++-- |  restrict number of tests+data Instances a = Instances Int a ++instance Testable a => Testable (Instances a) where+  resultiers (Instances r p) = takeTotal r (resultiers p)++takeTotal :: Int -> [[a]] -> [[a]]+takeTotal k xss | k <= 0 || null xss = []+takeTotal k (xs : xss) =+  let prefix  = take k xs+  in  prefix : takeTotal (k - length prefix) xss++-- | give a name for the property (will be pre-pended in failure messages)+data Prop a = Prop String a++instance Testable a => Testable (Prop a) where+  resultiers (Prop n p) = map (map (\ (args, f) -> (n : args, f))) $ resultiers p++-- | Hide the type argument existentially++data Test = forall a . Testable a => Test (a)++instance Testable Test where+  resultiers (Test p) = resultiers p++-- | combine properties (each must be true)+-- use `Test` (on each element of argument list for And)+-- to combine properties of different types, ++newtype And p = And [p]++instance Testable p => Testable (And p) where+  resultiers (And ps) = map concat $ map L.transpose $ map resultiers ps+++