git-annex/Utility/QuickCheck.hs

38 lines
986 B
Haskell
Raw Normal View History

2012-12-20 02:58:31 +00:00
{- QuickCheck instances
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
{-# LANGUAGE TypeSynonymInstances #-}
module Utility.QuickCheck where
import Test.QuickCheck
import Data.Time.Clock.POSIX
import System.Posix.Types
{- Times before the epoch are excluded. -}
instance Arbitrary POSIXTime where
arbitrary = nonNegative arbitrarySizedIntegral
instance Arbitrary EpochTime where
arbitrary = nonNegative arbitrarySizedIntegral
{- Pids are never negative, or 0. -}
instance Arbitrary ProcessID where
arbitrary = arbitrarySizedBoundedIntegral `suchThat` (> 0)
{- Inodes are never negative. -}
instance Arbitrary FileID where
arbitrary = nonNegative arbitrarySizedIntegral
{- File sizes are never negative. -}
instance Arbitrary FileOffset where
arbitrary = nonNegative arbitrarySizedIntegral
nonNegative :: (Num a, Ord a) => Gen a -> Gen a
nonNegative g = g `suchThat` (>= 0)