to make writing correct software cheaper.
- Free generators
- Free shrinking
- Cheap properties
- Property Combinators:
specify "inverse functions" $ inverseFunctions ( 1) (-1)
specify "equivalent functions" $ equivalent (( 1) . (- 1)) id
specify "transitivity" $ transitivity ((>) :: Int -> Int -> Bool)
specify "symmetry" $ symmetry ((==) :: Int -> Int -> Bool)- Test suite combinators:
ordSpec @Int Ord Int
(<=) :: Int -> Int -> Bool
is reflexive for "even Int"'s
OK, passed 100 tests.
is antisymmetric for "even Int"'s
OK, passed 100 tests.
is transitive for "even Int"'s
OK, passed 100 tests.
is equivalent to (\a b -> compare a b /= GT) for "even Int"'s
OK, passed 100 tests.
(>=) :: Int -> Int -> Bool
is reflexive for "even Int"'s
OK, passed 100 tests.
is antisymmetric for "even Int"'s
OK, passed 100 tests.
is transitive for "even Int"'s
OK, passed 100 tests.
is equivalent to (\a b -> compare a b /= LT) for "even Int"'s
OK, passed 100 tests.
(<) :: Int -> Int -> Bool
is antireflexive for "even Int"'s
OK, passed 100 tests.
is transitive for "even Int"'s
OK, passed 100 tests.
is equivalent to (\a b -> compare a b == LT) for "even Int"'s
OK, passed 100 tests.
(>) :: Int -> Int -> Bool
is antireflexive for "even Int"'s
OK, passed 100 tests.
is transitive for "even Int"'s
OK, passed 100 tests.
is equivalent to (\a b -> compare a b == GT) for "even Int"'s
OK, passed 100 tests.
data MyType = MyType
{ myRational :: Rational
, myBool :: Bool
} deriving (Show, Eq, Generic)
instance Validity MyType -- Implementation is derived via Generic
instance GenValid MyType -- Default implementation via GenericgenValid :: Gen MyType -- Free generator
shrinkValid :: MyType -> [MyType] -- Free _valid_ shrinking functionThere is a cachix cache for this project.
To use it, use cachix use validity or add the appropriate details to your nixos configuration.