checkers-0.4.5: Check properties on standard classes and data structures.

Test.QuickCheck.Checkers

Description

Some QuickCheck helpers

Synopsis

# Misc

type Test = (String, Property) Source #

Named test

type TestBatch = (String, [Test]) Source #

Named batch of tests

unbatch :: TestBatch -> [Test] Source #

Flatten a test batch for inclusion in another

checkBatch :: Args -> TestBatch -> IO () Source #

Run a batch of tests. See quickBatch and verboseBatch.

Check a batch tersely.

Check a batch verbosely.

type Unop a = a -> a Source #

Unary function, handy for type annotations

type Binop a = a -> a -> a Source #

Binary function, handy for type annotations

genR :: Random a => (a, a) -> Gen a Source #

involution :: (Show a, Arbitrary a, EqProp a) => (a -> a) -> Property Source #

f is its own inverse. See also inverse.

inverseL :: (EqProp b, Arbitrary b, Show b) => (a -> b) -> (b -> a) -> Property Source #

f is a left inverse of g. See also inverse.

inverse :: (EqProp a, Arbitrary a, Show a, EqProp b, Arbitrary b, Show b) => (a -> b) -> (b -> a) -> Property Source #

f is a left and right inverse of g. See also inverseL.

type FracT = Float Source #

Token Fractional type for tests

type NumT = Int Source #

Token Num type for tests

type OrdT = Int Source #

Token Ord type for tests

type T = Char Source #

Token uninteresting type for tests

# Generalized equality

class EqProp a where Source #

Types of values that can be tested for equality, perhaps through random sampling.

Minimal complete definition

(=-=)

Methods

(=-=) :: a -> a -> Property infix 4 Source #

Instances

 Source # Methods Source # Methods Source # Methods Source # Methods Source # Methods EqProp a => EqProp [a] Source # Methods(=-=) :: [a] -> [a] -> Property Source # EqProp a => EqProp (Maybe a) Source # Methods(=-=) :: Maybe a -> Maybe a -> Property Source # (Show a, Arbitrary a, EqProp b) => EqProp (a -> b) Source # Methods(=-=) :: (a -> b) -> (a -> b) -> Property Source # (EqProp a, EqProp b) => EqProp (Either a b) Source # Methods(=-=) :: Either a b -> Either a b -> Property Source # (EqProp a, EqProp b) => EqProp (a, b) Source # Methods(=-=) :: (a, b) -> (a, b) -> Property Source # (EqProp a, EqProp b, EqProp c) => EqProp (a, b, c) Source # Methods(=-=) :: (a, b, c) -> (a, b, c) -> Property Source # (EqProp a, EqProp b, EqProp c, EqProp d) => EqProp (a, b, c, d) Source # Methods(=-=) :: (a, b, c, d) -> (a, b, c, d) -> Property Source #

eq :: Eq a => a -> a -> Property Source #

For Eq types as EqProp types

type BinRel a = a -> a -> Bool Source #

reflexive :: (Arbitrary a, Show a) => BinRel a -> Property Source #

Reflexive property: a rel a

transitive :: (Arbitrary a, Show a) => BinRel a -> (a -> Gen a) -> Property Source #

Transitive property: a rel b && b rel c ==> a rel c. Generate a randomly, but use gen a to generate b and gen b to generate c. gen ought to satisfy rel fairly often.

symmetric :: (Arbitrary a, Show a) => BinRel a -> (a -> Gen a) -> Property Source #

Symmetric property: a rel b ==> b rel a. Generate a randomly, but use gen a to generate b. gen ought to satisfy rel fairly often.

antiSymmetric :: (Arbitrary a, Show a, Eq a) => BinRel a -> (a -> Gen a) -> Property Source #

Symmetric property: a rel b && b rel a ==> a == b. Generate a randomly, but use gen a to generate b. gen ought to satisfy both rel directions fairly often but not always.

leftId :: (Show a, Arbitrary a, EqProp a) => (i -> a -> a) -> i -> Property Source #

Has a given left identity, according to '(=-=)'

rightId :: (Show a, Arbitrary a, EqProp a) => (a -> i -> a) -> i -> Property Source #

Has a given right identity, according to '(=-=)'

bothId :: (Show a, Arbitrary a, EqProp a) => (a -> a -> a) -> a -> Property Source #

Has a given left and right identity, according to '(=-=)'

isAssoc :: (EqProp a, Show a, Arbitrary a) => (a -> a -> a) -> Property Source #

Associative, according to '(=-=)'

isCommut :: (EqProp a, Show a, Arbitrary a) => (a -> a -> a) -> Property Source #

Commutative, according to '(=-=)'

commutes :: EqProp z => (a -> a -> z) -> a -> a -> Property Source #

Commutative, according to '(=-=)'

data MonoidD a Source #

Explicit Monoid dictionary. Doesn't have to correspond to an actual Monoid instance, though see monoidD.

monoidD :: Monoid a => MonoidD a Source #

Monoid dictionary built from the Monoid methods.

endoMonoidD :: MonoidD (a -> a) Source #

Monoid dictionary for an unwrapped endomorphism. See also monoidD and Endo.

homomorphism :: (EqProp b, Show a, Arbitrary a) => MonoidD a -> MonoidD b -> (a -> b) -> [(String, Property)] Source #

Homomorphism properties with respect to given monoid dictionaries. See also monoidMorphism.

idempotent :: (Show a, Arbitrary a, EqProp a) => (a -> a) -> Property Source #

The unary function f is idempotent, i.e., f . f == f

idempotent2 :: (Show a, Arbitrary a, EqProp a) => (a -> a -> a) -> Property Source #

A binary function op is idempotent, i.e., x op x == x, for all x

idemElem :: EqProp a => (a -> a -> a) -> a -> Property Source #

A binary function op is has an idempotent element x, i.e., x op x == x

# Model-based (semantics-based) testing

class Model a b | a -> b where Source #

Minimal complete definition

model

Methods

model :: a -> b Source #

Instances

 Source # Methods Source # Methods Source # Methods Source # Methods Source # Methods Source # Methods (Model a b, Model a' b') => Model (a, a') (b, b') Source # Methodsmodel :: (a, a') -> (b, b') Source #

meq :: (Model a b, EqProp b) => a -> b -> Property Source #

meq1 :: (Model a b, Model a1 b1, EqProp b) => (a1 -> a) -> (b1 -> b) -> a1 -> Property Source #

meq2 :: (Model a b, Model a1 b1, Model a2 b2, EqProp b) => (a1 -> a2 -> a) -> (b1 -> b2 -> b) -> a1 -> a2 -> Property Source #

meq3 :: (Model a b, Model a1 b1, Model a2 b2, Model a3 b3, EqProp b) => (a1 -> a2 -> a3 -> a) -> (b1 -> b2 -> b3 -> b) -> a1 -> a2 -> a3 -> Property Source #

meq4 :: (Model a b, Model a1 b1, Model a2 b2, Model a3 b3, Model a4 b4, EqProp b) => (a1 -> a2 -> a3 -> a4 -> a) -> (b1 -> b2 -> b3 -> b4 -> b) -> a1 -> a2 -> a3 -> a4 -> Property Source #

meq5 :: (Model a b, Model a1 b1, Model a2 b2, Model a3 b3, Model a4 b4, Model a5 b5, EqProp b) => (a1 -> a2 -> a3 -> a4 -> a5 -> a) -> (b1 -> b2 -> b3 -> b4 -> b5 -> b) -> a1 -> a2 -> a3 -> a4 -> a5 -> Property Source #

eqModels :: (Model a b, EqProp b) => a -> a -> Property Source #

class Model1 f g | f -> g where Source #

Like Model but for unary type constructors.

Minimal complete definition

model1

Methods

model1 :: forall a. f a -> g a Source #

# Some handy testing types

arbs :: Arbitrary a => Int -> IO [a] Source #

Generate n arbitrary values

gens :: Int -> Gen a -> IO [a] Source #

Produce n values from a generator

(.&.) :: (Testable prop1, Testable prop2) => prop1 -> prop2 -> Property infixr 1 #

Nondeterministic choice: p1 .&. p2 picks randomly one of p1 and p2 to test. If you test the property 100 times it makes 100 random choices.

# Orphan instances

 Testable a => Testable [a] Source # Methodsproperty :: [a] -> Property # (Testable a, Testable b) => Testable (a, b) Source # Methodsproperty :: (a, b) -> Property #