Data.GenValidity.Hspec

These are standard tests that you should add to your hspec test suite if you implemented GenValidity instances for your own data types.

Use them like this:

mySpec :: Spec
mySpec = do
    genspec (proxy :: MyType)
    genspec (proxy :: MyOtherType)

HSpec will take care of the rest.

Documentation

module Data.GenValidity

proxy :: a

A value of arbitrary type, used to specify which type to generate a spec for.

genspec :: (Show a, Eq a, Data a, GenValidity a, Arbitrary a) => a -> Spec

A combination of arbitrarySpec and validitySpec

Example usage:

genspec (proxy :: MyData)

arbitrarySpec :: (Typeable a, Show a, Eq a, Data a, GenValidity a, Arbitrary a) => a -> Spec

A Spec that specifies that arbitrary only generates data that satisfy isValid and that shrink only produces data that satisfy isValid.

Example usage:

arbitrarySpec (proxy :: MyData)

validitySpec :: (Typeable a, Show a, Eq a, Data a, GenValidity a, Arbitrary a) => a -> Spec

A Spec that specifies that genValid only generates valid data and that genInvalid only generates invalid data.

In general it is a good idea to add this spec to your test suite if you write a custom implementation of genValid or genInvalid.

Example usage:

validitySpec (proxy :: MyData)