git-annex/Utility/QuickCheck.hs
Joey Hess c0bd202147
fix failing test case
An empty list of [ContentIdenfier] serialized to the same thing
as a single ContentIdentifier "". Avoid this ambiguity by requiring the
list be non-empty.
2019-03-06 14:27:15 -04:00

53 lines
1.4 KiB
Haskell

{- QuickCheck with additional instances
-
- Copyright 2012-2014 Joey Hess <id@joeyh.name>
-
- License: BSD-2-clause
-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
{-# LANGUAGE TypeSynonymInstances #-}
module Utility.QuickCheck
( module X
, module Utility.QuickCheck
) where
import Test.QuickCheck as X
import Data.Time.Clock.POSIX
import Data.Ratio
import System.Posix.Types
import Data.List.NonEmpty (NonEmpty(..))
import Prelude
{- Times before the epoch are excluded. Half with decimal and half without. -}
instance Arbitrary POSIXTime where
arbitrary = do
n <- nonNegative arbitrarySizedBoundedIntegral :: Gen Int
d <- nonNegative arbitrarySizedIntegral
withd <- arbitrary
return $ if withd
then fromIntegral n + fromRational (1 % max d 1)
else fromIntegral n
{- Pids are never negative, or 0. -}
instance Arbitrary ProcessID where
arbitrary = positive arbitrarySizedBoundedIntegral
{- Inodes are never negative. -}
instance Arbitrary FileID where
arbitrary = nonNegative arbitrarySizedIntegral
{- File sizes are never negative. -}
instance Arbitrary FileOffset where
arbitrary = nonNegative arbitrarySizedIntegral
{- Quickcheck lacks this instance. -}
instance Arbitrary l => Arbitrary (NonEmpty l) where
arbitrary = (:|) <$> arbitrary <*> arbitrary
nonNegative :: (Num a, Ord a) => Gen a -> Gen a
nonNegative g = g `suchThat` (>= 0)
positive :: (Num a, Ord a) => Gen a -> Gen a
positive g = g `suchThat` (> 0)