Test.Falsify.Interactive

Utilities for interaction with falsify in ghci

Documentation

falsify :: forall e a. Property' e a -> IO (Maybe e)

Try to falsify the given property

Reports the counter-example, if we find any.

falsify' :: forall e a. Property' e a -> IO (Maybe (NonEmpty e))

Generalization of falsify that reports the full shrink history

sample :: Gen a -> IO a

Sample generator

shrink :: forall a. (a -> Bool) -> Gen a -> IO (Maybe a)

Shrink counter-example

This will run the generator repeatedly until it finds a counter-example to the given property, and will then shrink it.

Returns Nothing if no counter-example could be found.

shrink' :: forall e a. (a -> Maybe e) -> Gen a -> IO (Maybe (NonEmpty e))

Generalization of shrink. Returns the full shrink history.

Re-exports

module Test.Falsify.Property

Functions

pattern Fn :: (a -> b) -> Fun a b

Pattern synonym useful when generating functions of one argument

pattern Fn2 :: (a -> b -> c) -> Fun (a, b) c

Pattern synonym useful when generating functions of two arguments

pattern Fn3 :: (a -> b -> c -> d) -> Fun (a, b, c) d

Pattern synonym useful when generating functions of three arguments