blob: c88bd956292831b94bae92bdef66eea11f634136 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
--------------------------------------------------------------------------------
module Xanthous.RandomSpec (main, test) where
--------------------------------------------------------------------------------
import Test.Prelude
--------------------------------------------------------------------------------
import Control.Monad.Random
--------------------------------------------------------------------------------
import Xanthous.Random
import Xanthous.Orphans ()
import qualified Data.Interval as Interval
import Data.Interval (Interval, Extended (Finite), (<=..<=))
--------------------------------------------------------------------------------
main :: IO ()
main = defaultMain test
test :: TestTree
test = testGroup "Xanthous.Random"
[ testGroup "chooseSubset"
[ testProperty "chooses a subset"
$ \(l :: [Int]) (Positive (r :: Double)) -> randomTest $ do
ss <- chooseSubset r l
pure $ all (`elem` l) ss
]
, testGroup "chooseRange"
[ testProperty "chooses in the range"
$ \(rng :: Interval Int) ->
not (Interval.null rng)
==> randomTest ( do
chooseRange rng >>= \case
Just r -> pure
. counterexample (show r)
$ r `Interval.member` rng
Nothing -> pure $ property Discard
)
, testProperty "nonEmpty range is never empty"
$ \ (lower :: Int) (NonZero diff) -> randomTest $ do
let upper = lower + diff
r <- chooseRange (Finite lower <=..<= Finite upper)
pure $ isJust r
]
]
where
randomTest prop = evalRandT prop . mkStdGen =<< arbitrary
|