{-# LANGUAGE AllowAmbiguousTypes #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeApplications #-}

-- | Eq properties
--
-- You will need @TypeApplications@ to use these.
module Test.Validity.Eq
  ( eqSpec,
    eqSpecOnArbitrary,
    eqSpecOnGen,
  )
where

import Data.Data
import Data.GenValidity
import Test.Hspec
import Test.QuickCheck
import Test.Validity.Functions
import Test.Validity.Relations
import Test.Validity.Utils

eqTypeStr ::
  forall a.
  Typeable a =>
  String
eqTypeStr :: String
eqTypeStr = String -> String
forall k (a :: k). Typeable a => String -> String
binRelStr @a String
"=="

neqTypeStr ::
  forall a.
  Typeable a =>
  String
neqTypeStr :: String
neqTypeStr = String -> String
forall k (a :: k). Typeable a => String -> String
binRelStr @a String
"/="

-- | Standard test spec for properties of Eq instances for valid values
--
-- Example usage:
--
-- > eqSpec @Int
eqSpec ::
  forall a.
  (Show a, Eq a, Typeable a, GenValid a) =>
  Spec
eqSpec :: Spec
eqSpec = Gen a -> String -> (a -> [a]) -> Spec
forall a.
(Show a, Eq a, Typeable a) =>
Gen a -> String -> (a -> [a]) -> Spec
eqSpecOnGen @a Gen a
forall a. GenValid a => Gen a
genValid String
"valid" a -> [a]
forall a. GenValid a => a -> [a]
shrinkValid

-- | Standard test spec for properties of Eq instances for arbitrary values
--
-- Example usage:
--
-- > eqSpecOnArbitrary @Int
eqSpecOnArbitrary ::
  forall a.
  (Show a, Eq a, Typeable a, Arbitrary a) =>
  Spec
eqSpecOnArbitrary :: Spec
eqSpecOnArbitrary = Gen a -> String -> (a -> [a]) -> Spec
forall a.
(Show a, Eq a, Typeable a) =>
Gen a -> String -> (a -> [a]) -> Spec
eqSpecOnGen @a Gen a
forall a. Arbitrary a => Gen a
arbitrary String
"arbitrary" a -> [a]
forall a. Arbitrary a => a -> [a]
shrink

-- | Standard test spec for properties of Eq instances for values generated by a given generator (and name for that generator).
--
-- Example usage:
--
-- > eqSpecOnGen ((* 2) <$> genValid @Int) "even"
eqSpecOnGen ::
  forall a.
  (Show a, Eq a, Typeable a) =>
  Gen a ->
  String ->
  (a -> [a]) ->
  Spec
eqSpecOnGen :: Gen a -> String -> (a -> [a]) -> Spec
eqSpecOnGen Gen a
gen String
genname a -> [a]
s =
  Spec -> Spec
forall a. SpecWith a -> SpecWith a
parallel (Spec -> Spec) -> Spec -> Spec
forall a b. (a -> b) -> a -> b
$ do
    let name :: String
name = Typeable a => String
forall k (a :: k). Typeable a => String
nameOf @a
        funeqstr :: String
funeqstr = Typeable a => String
forall a. Typeable a => String
eqTypeStr @a
        funneqstr :: String
funneqstr = Typeable a => String
forall a. Typeable a => String
neqTypeStr @a
        gen2 :: Gen (a, a)
gen2 = (,) (a -> a -> (a, a)) -> Gen a -> Gen (a -> (a, a))
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> Gen a
gen Gen (a -> (a, a)) -> Gen a -> Gen (a, a)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> Gen a
gen
        gen3 :: Gen (a, a, a)
gen3 = (,,) (a -> a -> a -> (a, a, a)) -> Gen a -> Gen (a -> a -> (a, a, a))
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> Gen a
gen Gen (a -> a -> (a, a, a)) -> Gen a -> Gen (a -> (a, a, a))
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> Gen a
gen Gen (a -> (a, a, a)) -> Gen a -> Gen (a, a, a)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> Gen a
gen
        s2 :: (a, a) -> [(a, a)]
s2 = (a -> [a]) -> (a, a) -> [(a, a)]
forall a. (a -> [a]) -> (a, a) -> [(a, a)]
shrinkT2 a -> [a]
s
    String -> Spec -> Spec
forall a. HasCallStack => String -> SpecWith a -> SpecWith a
describe (String
"Eq " String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
name) (Spec -> Spec) -> Spec -> Spec
forall a b. (a -> b) -> a -> b
$ do
      let eq :: a -> a -> Bool
eq = Eq a => a -> a -> Bool
forall a. Eq a => a -> a -> Bool
(==) @a
          neq :: a -> a -> Bool
neq = Eq a => a -> a -> Bool
forall a. Eq a => a -> a -> Bool
(/=) @a
      String -> Spec -> Spec
forall a. HasCallStack => String -> SpecWith a -> SpecWith a
describe String
funeqstr (Spec -> Spec) -> Spec -> Spec
forall a b. (a -> b) -> a -> b
$ do
        String -> Property -> SpecWith (Arg Property)
forall a.
(HasCallStack, Example a) =>
String -> a -> SpecWith (Arg a)
it
          ( [String] -> String
unwords
              [ String
"is reflexive for",
                String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
genname,
                String
name String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"s"
              ]
          )
          (Property -> SpecWith (Arg Property))
-> Property -> SpecWith (Arg Property)
forall a b. (a -> b) -> a -> b
$ (a -> a -> Bool) -> Gen a -> (a -> [a]) -> Property
forall a.
Show a =>
(a -> a -> Bool) -> Gen a -> (a -> [a]) -> Property
reflexivityOnGen a -> a -> Bool
eq Gen a
gen a -> [a]
s
        String -> Property -> SpecWith (Arg Property)
forall a.
(HasCallStack, Example a) =>
String -> a -> SpecWith (Arg a)
it
          ( [String] -> String
unwords
              [ String
"is symmetric for",
                String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
genname,
                String
name String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"s"
              ]
          )
          (Property -> SpecWith (Arg Property))
-> Property -> SpecWith (Arg Property)
forall a b. (a -> b) -> a -> b
$ (a -> a -> Bool) -> Gen (a, a) -> (a -> [a]) -> Property
forall a.
Show a =>
(a -> a -> Bool) -> Gen (a, a) -> (a -> [a]) -> Property
symmetryOnGens a -> a -> Bool
eq Gen (a, a)
gen2 a -> [a]
s
        String -> Property -> SpecWith (Arg Property)
forall a.
(HasCallStack, Example a) =>
String -> a -> SpecWith (Arg a)
it
          ( [String] -> String
unwords
              [ String
"is transitive for",
                String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
genname,
                String
name String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"s"
              ]
          )
          (Property -> SpecWith (Arg Property))
-> Property -> SpecWith (Arg Property)
forall a b. (a -> b) -> a -> b
$ (a -> a -> Bool) -> Gen (a, a, a) -> (a -> [a]) -> Property
forall a.
Show a =>
(a -> a -> Bool) -> Gen (a, a, a) -> (a -> [a]) -> Property
transitivityOnGens a -> a -> Bool
eq Gen (a, a, a)
gen3 a -> [a]
s
        String -> Property -> SpecWith (Arg Property)
forall a.
(HasCallStack, Example a) =>
String -> a -> SpecWith (Arg a)
it
          ( [String] -> String
unwords
              [ String
"is equivalent to (\\a b -> not $ a /= b) for",
                String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
genname,
                String
name String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"s"
              ]
          )
          (Property -> SpecWith (Arg Property))
-> Property -> SpecWith (Arg Property)
forall a b. (a -> b) -> a -> b
$ (a -> a -> Bool)
-> (a -> a -> Bool)
-> Gen (a, a)
-> ((a, a) -> [(a, a)])
-> Property
forall a b c.
(Show a, Show b, Show c, Eq c) =>
(a -> b -> c)
-> (a -> b -> c) -> Gen (a, b) -> ((a, b) -> [(a, b)]) -> Property
equivalentOnGens2 a -> a -> Bool
eq (\a
a a
b -> Bool -> Bool
not (Bool -> Bool) -> Bool -> Bool
forall a b. (a -> b) -> a -> b
$ a
a a -> a -> Bool
`neq` a
b) Gen (a, a)
gen2 (a, a) -> [(a, a)]
s2
      String -> Spec -> Spec
forall a. HasCallStack => String -> SpecWith a -> SpecWith a
describe String
funneqstr (Spec -> Spec) -> Spec -> Spec
forall a b. (a -> b) -> a -> b
$ do
        String -> Property -> SpecWith (Arg Property)
forall a.
(HasCallStack, Example a) =>
String -> a -> SpecWith (Arg a)
it
          ( [String] -> String
unwords
              [ String
"is antireflexive for",
                String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
genname,
                String
name String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"s"
              ]
          )
          (Property -> SpecWith (Arg Property))
-> Property -> SpecWith (Arg Property)
forall a b. (a -> b) -> a -> b
$ (a -> a -> Bool) -> Gen a -> (a -> [a]) -> Property
forall a.
Show a =>
(a -> a -> Bool) -> Gen a -> (a -> [a]) -> Property
antireflexivityOnGen a -> a -> Bool
neq Gen a
gen a -> [a]
s
        String -> Property -> SpecWith (Arg Property)
forall a.
(HasCallStack, Example a) =>
String -> a -> SpecWith (Arg a)
it
          ( [String] -> String
unwords
              [ String
"is equivalent to (\\a b -> not $ a == b) for",
                String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
genname,
                String
name String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"\"" String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"s"
              ]
          )
          (Property -> SpecWith (Arg Property))
-> Property -> SpecWith (Arg Property)
forall a b. (a -> b) -> a -> b
$ (a -> a -> Bool)
-> (a -> a -> Bool)
-> Gen (a, a)
-> ((a, a) -> [(a, a)])
-> Property
forall a b c.
(Show a, Show b, Show c, Eq c) =>
(a -> b -> c)
-> (a -> b -> c) -> Gen (a, b) -> ((a, b) -> [(a, b)]) -> Property
equivalentOnGens2 a -> a -> Bool
neq (\a
a a
b -> Bool -> Bool
not (Bool -> Bool) -> Bool -> Bool
forall a b. (a -> b) -> a -> b
$ a
a a -> a -> Bool
`eq` a
b) Gen (a, a)
gen2 (a, a) -> [(a, a)]
s2