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|
#!/usr/bin/env runhaskell
--
-- Uses multi-param type classes
--
import Test.QuickCheck.Batch
import Test.QuickCheck
import Text.Show.Functions
import Data.Char
import Data.Int
import Data.List
import Data.Maybe
import Data.Word
import System.IO
import System.Environment
import System.IO.Unsafe
import System.Random
import Control.Monad ( liftM2 )
import Control.Monad.Instances ()
import Text.Printf
import Debug.Trace
import Foreign.Ptr
import Data.ByteString.Lazy (ByteString(..), pack , unpack)
import qualified Data.ByteString.Lazy as L
import qualified Data.ByteString.Lazy.Internal as L
import Data.ByteString.Fusion
import qualified Data.ByteString as P
import qualified Data.ByteString.Lazy as L
import qualified Data.ByteString.Char8 as PC
import qualified Data.ByteString.Lazy.Char8 as LC
import qualified Data.ByteString as P
import qualified Data.ByteString.Internal as P
import qualified Data.ByteString.Char8 as C
import qualified Data.ByteString.Lazy.Char8 as D
import Data.ByteString.Fusion
import Prelude hiding (abs)
-- Enable this to get verbose test output. Including the actual tests.
debug = False
mytest :: Testable a => a -> Int -> IO ()
mytest a n = mycheck defaultConfig
{ configMaxTest=n
, configEvery= \n args -> if debug then show n ++ ":\n" ++ unlines args else [] } a
mycheck :: Testable a => Config -> a -> IO ()
mycheck config a =
do let rnd = mkStdGen 99
mytests config (evaluate a) rnd 0 0 []
mytests :: Config -> Gen Result -> StdGen -> Int -> Int -> [[String]] -> IO ()
mytests config gen rnd0 ntest nfail stamps
| ntest == configMaxTest config = do done "OK," ntest stamps
| nfail == configMaxFail config = do done "Arguments exhausted after" ntest stamps
| otherwise =
do putStr (configEvery config ntest (arguments result)) >> hFlush stdout
case ok result of
Nothing ->
mytests config gen rnd1 ntest (nfail+1) stamps
Just True ->
mytests config gen rnd1 (ntest+1) nfail (stamp result:stamps)
Just False ->
putStr ( "Falsifiable after "
++ show ntest
++ " tests:\n"
++ unlines (arguments result)
) >> hFlush stdout
where
result = generate (configSize config ntest) rnd2 gen
(rnd1,rnd2) = split rnd0
done :: String -> Int -> [[String]] -> IO ()
done mesg ntest stamps =
do putStr ( mesg ++ " " ++ show ntest ++ " tests" ++ table )
where
table = display
. map entry
. reverse
. sort
. map pairLength
. group
. sort
. filter (not . null)
$ stamps
display [] = ".\n"
display [x] = " (" ++ x ++ ").\n"
display xs = ".\n" ++ unlines (map (++ ".") xs)
pairLength xss@(xs:_) = (length xss, xs)
entry (n, xs) = percentage n ntest
++ " "
++ concat (intersperse ", " xs)
percentage n m = show ((100 * n) `div` m) ++ "%"
------------------------------------------------------------------------
instance Arbitrary Char where
arbitrary = choose ('a', 'i')
coarbitrary c = variant (ord c `rem` 4)
instance (Arbitrary a, Arbitrary b) => Arbitrary (PairS a b) where
arbitrary = liftM2 (:*:) arbitrary arbitrary
coarbitrary (a :*: b) = coarbitrary a . coarbitrary b
instance Arbitrary Word8 where
arbitrary = choose (97, 105)
coarbitrary c = variant (fromIntegral ((fromIntegral c) `rem` 4))
instance Arbitrary Int64 where
arbitrary = sized $ \n -> choose (-fromIntegral n,fromIntegral n)
coarbitrary n = variant (fromIntegral (if n >= 0 then 2*n else 2*(-n) + 1))
instance Arbitrary a => Arbitrary (MaybeS a) where
arbitrary = do a <- arbitrary ; elements [NothingS, JustS a]
coarbitrary NothingS = variant 0
coarbitrary _ = variant 1 -- ok?
{-
instance Arbitrary Char where
arbitrary = choose ('\0', '\255') -- since we have to test words, unlines too
coarbitrary c = variant (ord c `rem` 16)
instance Arbitrary Word8 where
arbitrary = choose (minBound, maxBound)
coarbitrary c = variant (fromIntegral ((fromIntegral c) `rem` 16))
-}
instance Random Word8 where
randomR = integralRandomR
random = randomR (minBound,maxBound)
instance Random Int64 where
randomR = integralRandomR
random = randomR (minBound,maxBound)
integralRandomR :: (Integral a, RandomGen g) => (a,a) -> g -> (a,g)
integralRandomR (a,b) g = case randomR (fromIntegral a :: Integer,
fromIntegral b :: Integer) g of
(x,g) -> (fromIntegral x, g)
instance Arbitrary L.ByteString where
arbitrary = arbitrary >>= return . L.fromChunks . filter (not. P.null) -- maintain the invariant.
coarbitrary s = coarbitrary (L.unpack s)
instance Arbitrary P.ByteString where
arbitrary = P.pack `fmap` arbitrary
coarbitrary s = coarbitrary (P.unpack s)
------------------------------------------------------------------------
--
-- We're doing two forms of testing here. Firstly, model based testing.
-- For our Lazy and strict bytestring types, we have model types:
--
-- i.e. Lazy == Byte
-- \\ //
-- List
--
-- That is, the Lazy type can be modeled by functions in both the Byte
-- and List type. For each of the 3 models, we have a set of tests that
-- check those types match.
--
-- The Model class connects a type and its model type, via a conversion
-- function.
--
--
class Model a b where
model :: a -> b -- get the abstract vale from a concrete value
--
-- Connecting our Lazy and Strict types to their models. We also check
-- the data invariant on Lazy types.
--
-- These instances represent the arrows in the above diagram
--
instance Model B P where model = abstr . checkInvariant
instance Model P [W] where model = P.unpack
instance Model P [Char] where model = PC.unpack
instance Model B [W] where model = L.unpack . checkInvariant
instance Model B [Char] where model = LC.unpack . checkInvariant
-- Types are trivially modeled by themselves
instance Model Bool Bool where model = id
instance Model Int Int where model = id
instance Model Int64 Int64 where model = id
instance Model Int64 Int where model = fromIntegral
instance Model Word8 Word8 where model = id
instance Model Ordering Ordering where model = id
-- More structured types are modeled recursively, using the NatTrans class from Gofer.
class (Functor f, Functor g) => NatTrans f g where
eta :: f a -> g a
-- The transformation of the same type is identity
instance NatTrans [] [] where eta = id
instance NatTrans Maybe Maybe where eta = id
instance NatTrans ((->) X) ((->) X) where eta = id
instance NatTrans ((->) W) ((->) W) where eta = id
-- We have a transformation of pairs, if the pairs are in Model
instance Model f g => NatTrans ((,) f) ((,) g) where eta (f,a) = (model f, a)
-- And finally, we can take any (m a) to (n b), if we can Model m n, and a b
instance (NatTrans m n, Model a b) => Model (m a) (n b) where model x = fmap model (eta x)
------------------------------------------------------------------------
-- In a form more useful for QC testing (and it's lazy)
checkInvariant :: L.ByteString -> L.ByteString
checkInvariant cs0 = check cs0
where check L.Empty = L.Empty
check (L.Chunk c cs)
| P.null c = error ("invariant violation: " ++ show cs0)
| otherwise = L.Chunk c (check cs)
abstr :: L.ByteString -> P.ByteString
abstr = P.concat . L.toChunks
-- Some short hand.
type X = Int
type W = Word8
type P = P.ByteString
type B = L.ByteString
------------------------------------------------------------------------
--
-- These comparison functions handle wrapping and equality.
--
-- A single class for these would be nice, but note that they differe in
-- the number of arguments, and those argument types, so we'd need HList
-- tricks. See here: http://okmij.org/ftp/Haskell/vararg-fn.lhs
--
eq1 f g = \a ->
model (f a) == g (model a)
eq2 f g = \a b ->
model (f a b) == g (model a) (model b)
eq3 f g = \a b c ->
model (f a b c) == g (model a) (model b) (model c)
eq4 f g = \a b c d ->
model (f a b c d) == g (model a) (model b) (model c) (model d)
eq5 f g = \a b c d e ->
model (f a b c d e) == g (model a) (model b) (model c) (model d) (model e)
--
-- And for functions that take non-null input
--
eqnotnull1 f g = \x -> (not (isNull x)) ==> eq1 f g x
eqnotnull2 f g = \x y -> (not (isNull y)) ==> eq2 f g x y
eqnotnull3 f g = \x y z -> (not (isNull z)) ==> eq3 f g x y z
class IsNull t where isNull :: t -> Bool
instance IsNull L.ByteString where isNull = L.null
instance IsNull P.ByteString where isNull = P.null
main = do
x <- getArgs
let n = if null x then 100 else read . head $ x
mapM_ (\(s,a) -> printf "%-25s: " s >> a n) tests
--
-- Test that, after loop fusion, our code behaves the same as the
-- unfused lazy or list models. Use -ddump-simpl to also check that
-- rules are firing for each case.
--
tests = -- 29/5/06, all tests are fusing:
[("down/down list", mytest prop_downdown_list) -- checked
,("down/filter list", mytest prop_downfilter_list) -- checked
,("down/map list", mytest prop_downmap_list) -- checked
,("filter/down lazy", mytest prop_filterdown_lazy) -- checked
,("filter/down list", mytest prop_filterdown_list) -- checked
,("filter/filter lazy", mytest prop_filterfilter_lazy) -- checked
,("filter/filter list", mytest prop_filterfilter_list) -- checked
,("filter/map lazy", mytest prop_filtermap_lazy) -- checked
,("filter/map list", mytest prop_filtermap_list) -- checked
,("filter/up lazy", mytest prop_filterup_lazy) -- checked
,("filter/up list", mytest prop_filterup_list) -- checked
,("map/down lazy", mytest prop_mapdown_lazy) -- checked
,("map/down list", mytest prop_mapdown_list) -- checked
,("map/filter lazy", mytest prop_mapfilter_lazy) -- checked
,("map/filter list", mytest prop_mapfilter_list) -- checked
,("map/map lazy", mytest prop_mapmap_lazy) -- checked
,("map/map list", mytest prop_mapmap_list) -- checked
,("map/up lazy", mytest prop_mapup_lazy) -- checked
,("map/up list", mytest prop_mapup_list) -- checked
,("up/filter lazy", mytest prop_upfilter_lazy) -- checked
,("up/filter list", mytest prop_upfilter_list) -- checked
,("up/map lazy", mytest prop_upmap_lazy) -- checked
,("up/map list", mytest prop_upmap_list) -- checked
,("up/up lazy", mytest prop_upup_lazy) -- checked
,("up/up list", mytest prop_upup_list) -- checked
,("noacc/noacc lazy", mytest prop_noacc_noacc_lazy) -- checked
,("noacc/noacc list", mytest prop_noacc_noacc_list) -- checked
,("noacc/up lazy", mytest prop_noacc_up_lazy) -- checked
,("noacc/up list", mytest prop_noacc_up_list) -- checked
,("up/noacc lazy", mytest prop_up_noacc_lazy) -- checked
,("up/noacc list", mytest prop_up_noacc_list) -- checked
,("map/noacc lazy", mytest prop_map_noacc_lazy) -- checked
,("map/noacc list", mytest prop_map_noacc_list) -- checked
,("noacc/map lazy", mytest prop_noacc_map_lazy) -- checked
,("noacc/map list", mytest prop_noacc_map_list) -- checked
,("filter/noacc lazy", mytest prop_filter_noacc_lazy) -- checked
,("filter/noacc list", mytest prop_filter_noacc_list) -- checked
,("noacc/filter lazy", mytest prop_noacc_filter_lazy) -- checked
,("noacc/filter list", mytest prop_noacc_filter_list) -- checked
,("noacc/down lazy", mytest prop_noacc_down_lazy) -- checked
,("noacc/down list", mytest prop_noacc_down_list) -- checked
-- ,("down/noacc lazy", mytest prop_down_noacc_lazy) -- checked
,("down/noacc list", mytest prop_down_noacc_list) -- checked
,("length/loop list", mytest prop_lengthloop_list)
-- ,("length/loop lazy", mytest prop_lengthloop_lazy)
,("maximum/loop list", mytest prop_maximumloop_list)
-- ,("maximum/loop lazy", mytest prop_maximumloop_lazy)
,("minimum/loop list", mytest prop_minimumloop_list)
-- ,("minimum/loop lazy", mytest prop_minimumloop_lazy)
]
prop_upup_list = eq3
(\f g -> P.foldl f (0::Int) . P.scanl g (0::W))
((\f g -> foldl f (0::Int) . scanl g (0::W)) :: (X -> W -> X) -> (W -> W -> W) -> [W] -> X)
prop_upup_lazy = eq3
(\f g -> L.foldl f (0::X) . L.scanl g (0::W))
(\f g -> P.foldl f (0::X) . P.scanl g (0::W))
prop_mapmap_list = eq3
(\f g -> P.map f . P.map g)
((\f g -> map f . map g) :: (W -> W) -> (W -> W) -> [W] -> [W])
prop_mapmap_lazy = eq3
(\f g -> L.map f . L.map g)
(\f g -> P.map f . P.map g)
prop_filterfilter_list = eq3
(\f g -> P.filter f . P.filter g)
((\f g -> filter f . filter g) :: (W -> Bool) -> (W -> Bool) -> [W] -> [W])
prop_filterfilter_lazy = eq3
(\f g -> L.filter f . L.filter g)
(\f g -> P.filter f . P.filter g)
prop_mapfilter_list = eq3
(\f g -> P.filter f . P.map g)
((\f g -> filter f . map g) :: (W -> Bool) -> (W -> W) -> [W] -> [W])
prop_mapfilter_lazy = eq3
(\f g -> L.filter f . L.map g)
(\f g -> P.filter f . P.map g)
prop_filtermap_list = eq3
(\f g -> P.map f . P.filter g)
((\f g -> map f . filter g) :: (W -> W) -> (W -> Bool) -> [W] -> [W])
prop_filtermap_lazy = eq3
(\f g -> L.map f . L.filter g)
(\f g -> P.map f . P.filter g)
prop_mapup_list = eq3
(\f g -> P.foldl g (0::W) . P.map f)
((\f g -> foldl g (0::W) . map f) :: (W -> W) -> (W -> W -> W) -> [W] -> W)
prop_mapup_lazy = eq3
(\f g -> L.foldl g (0::W) . L.map f) -- n.b. scan doesn't fuse here, atm
(\f g -> P.foldl g (0::W) . P.map f)
prop_upmap_list = eq3
(\f g -> P.map f . P.scanl g (0::W))
((\f g -> map f . scanl g (0::W)) :: (W -> W) -> (W -> W -> W) -> [W] -> [W])
prop_upmap_lazy = eq3
(\f g -> L.map f . L.scanl g (0::W))
(\f g -> P.map f . P.scanl g (0::W))
prop_filterup_list = eq3
(\f g -> P.foldl g (0::W) . P.filter f)
((\f g -> foldl g (0::W) . filter f) :: (W -> Bool) -> (W -> W -> W) -> [W] -> W)
prop_filterup_lazy = eq3
(\f g -> L.foldl g (0::W) . L.filter f)
(\f g -> P.foldl g (0::W) . P.filter f)
prop_upfilter_list = eq3
(\f g -> P.filter f . P.scanl g (0::W))
((\f g -> filter f . scanl g (0::W)) :: (W -> Bool) -> (W -> W -> W) -> [W] -> [W])
prop_upfilter_lazy = eq3
(\f g -> L.filter f . L.scanl g (0::W))
(\f g -> P.filter f . P.scanl g (0::W))
prop_downdown_list = eq3
(\f g -> P.foldr f (0::X) . P.scanr g (0::W))
((\f g -> foldr f (0::X) . scanr g (0::W)) :: (W -> X -> X) -> (W -> W -> W) -> [W] -> X)
{-
-- no lazy scanr yet
prop_downdown_lazy = eq3
(\f g -> L.foldr f (0::X) . L.scanr g (0::W))
(\f g -> P.foldr f (0::X) . P.scanr g (0::W))
-}
prop_mapdown_list = eq3
(\f g -> P.foldr g (0::W) . P.map f)
((\f g -> foldr g (0::W) . map f) :: (W -> W) -> (W -> W -> W) -> [W] -> W)
prop_mapdown_lazy = eq3
(\f g -> L.foldr g (0::W) . L.map f) -- n.b. scan doesn't fuse here, atm
(\f g -> P.foldr g (0::W) . P.map f)
prop_downmap_list = eq3
(\f g -> P.map f . P.scanr g (0::W))
((\f g -> map f . scanr g (0::W)) :: (W -> W) -> (W -> W -> W) -> [W] -> [W])
{-
prop_downmap_lazy = eq3
(\f g -> L.map f . L.scanr g (0::W))
(\f g -> P.map f . P.scanr g (0::W))
-}
prop_filterdown_list = eq3
(\f g -> P.foldr g (0::W) . P.filter f)
((\f g -> foldr g (0::W) . filter f) :: (W -> Bool) -> (W -> W -> W) -> [W] -> W)
prop_filterdown_lazy = eq3
(\f g -> L.foldr g (0::W) . L.filter f) -- n.b. scan doesn't fuse here, atm
(\f g -> P.foldr g (0::W) . P.filter f)
prop_downfilter_list = eq3
(\f g -> P.filter f . P.scanr g (0::W))
((\f g -> filter f . scanr g (0::W)) :: (W -> Bool) -> (W -> W -> W) -> [W] -> [W])
{-
prop_downfilter_lazy = eq3
(\f g -> L.filter f . L.scanr g (0::W))
(\f g -> P.filter f . P.scanr g (0::W))
-}
prop_noacc_noacc_list = eq5
(\f g h i -> (P.map f . P.filter g) . (P.map h . P.filter i))
((\f g h i -> ( map f . filter g) . ( map h . filter i))
:: (W -> W) -> (W -> Bool) -> (W -> W) -> (W -> Bool) -> [W] -> [W])
prop_noacc_noacc_lazy = eq5
(\f g h i -> (L.map f . L.filter g) . (L.map h . L.filter i))
(\f g h i -> (P.map f . P.filter g) . (P.map h . P.filter i))
prop_noacc_up_list = eq4
( \g h i -> P.foldl g (0::W) . (P.map h . P.filter i))
((\g h i -> foldl g (0::W) . ( map h . filter i))
:: (W -> W -> W) -> (W -> W) -> (W -> Bool) -> [W] -> W)
prop_noacc_up_lazy = eq4
(\g h i -> L.foldl g (0::W) . (L.map h . L.filter i))
(\g h i -> P.foldl g (0::W) . (P.map h . P.filter i))
prop_up_noacc_list = eq4
( \g h i -> (P.map h . P.filter i) . P.scanl g (0::W))
((\g h i -> ( map h . filter i) . scanl g (0::W))
:: (W -> W -> W) -> (W -> W) -> (W -> Bool) -> [W] -> [W])
prop_up_noacc_lazy = eq4
(\g h i -> (L.map h . L.filter i) . L.scanl g (0::W))
(\g h i -> (P.map h . P.filter i) . P.scanl g (0::W))
prop_map_noacc_list = eq4
( \g h i -> (P.map h . P.filter i) . P.map g)
((\g h i -> ( map h . filter i) . map g)
:: (W -> W) -> (W -> W) -> (W -> Bool) -> [W] -> [W])
prop_map_noacc_lazy = eq4
(\g h i -> (L.map h . L.filter i) . L.map g)
(\g h i -> (P.map h . P.filter i) . P.map g)
prop_noacc_map_list = eq4
( \g h i -> P.map g . (P.map h . P.filter i))
((\g h i -> map g . ( map h . filter i))
:: (W -> W) -> (W -> W) -> (W -> Bool) -> [W] -> [W])
prop_noacc_map_lazy = eq4
(\g h i -> L.map g . (L.map h . L.filter i))
(\g h i -> P.map g . (P.map h . P.filter i))
prop_filter_noacc_list = eq4
( \g h i -> (P.map h . P.filter i) . P.filter g)
((\g h i -> ( map h . filter i) . filter g)
:: (W -> Bool) -> (W -> W) -> (W -> Bool) -> [W] -> [W])
prop_filter_noacc_lazy = eq4
(\g h i -> (L.map h . L.filter i) . L.filter g)
(\g h i -> (P.map h . P.filter i) . P.filter g)
prop_noacc_filter_list = eq4
( \g h i -> P.filter g . (P.map h . P.filter i))
((\g h i -> filter g . ( map h . filter i))
:: (W -> Bool) -> (W -> W) -> (W -> Bool) -> [W] -> [W])
prop_noacc_filter_lazy = eq4
(\g h i -> L.filter g . (L.map h . L.filter i))
(\g h i -> P.filter g . (P.map h . P.filter i))
prop_noacc_down_list = eq4
( \g h i -> P.foldr g (0::W) . (P.map h . P.filter i))
((\g h i -> foldr g (0::W) . ( map h . filter i))
:: (W -> W -> W) -> (W -> W) -> (W -> Bool) -> [W] -> W)
prop_noacc_down_lazy = eq4
(\g h i -> L.foldr g (0::W) . (L.map h . L.filter i))
(\g h i -> P.foldr g (0::W) . (P.map h . P.filter i))
prop_down_noacc_list = eq4
( \g h i -> (P.map h . P.filter i) . P.scanr g (0::W))
((\g h i -> ( map h . filter i) . scanr g (0::W))
:: (W -> W -> W) -> (W -> W) -> (W -> Bool) -> [W] -> [W])
{-
prop_down_noacc_lazy = eq4
(\g h i -> (L.map h . L.filter i) . L.scanl g (0::W))
(\g h i -> (P.map h . P.filter i) . P.scanl g (0::W))
-}
------------------------------------------------------------------------
prop_lengthloop_list = eq2
(\f -> P.length . P.filter f)
((\f -> length . filter f) :: (W -> Bool) -> [W] -> X)
{-
prop_lengthloop_lazy = eq2
(\f g -> L.length . L.filter f) -- n.b. scan doesn't fuse here, atm
(\f g -> P.length . P.filter f)
-}
prop_maximumloop_list = eqnotnull2
(\f -> P.maximum . P.map f) -- so we don't get null strings
((\f -> maximum . map f) :: (W -> W) -> [W] -> W)
{-
prop_maximumloop_lazy = eq2
(\f g -> L.maximum . L.filter f) -- n.b. scan doesn't fuse here, atm
(\f g -> P.maximum . P.filter f)
-}
prop_minimumloop_list = eqnotnull2
(\f -> P.minimum . P.map f)
((\f -> minimum . map f) :: (W -> W) -> [W] -> W)
{-
prop_minimumloop_lazy = eq2
(\f g -> L.minimum . L.filter f) -- n.b. scan doesn't fuse here, atm
(\f g -> P.minimum . P.filter f)
-}
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