{-- Haskell98! --}

-- Simple IO Regions. Tests
-- $Id: IORegions98Test.hs,v 1.1 2006/01/24 00:29:38 oleg Exp oleg $

module IORegions98Test where

import IORegions98E
import Monad
import Data.Typeable

-- We define the following just as an attempt to break the safety
-- gurantee. Users should NOT add the following two instances.
-- However, even if they do, the safety gurantees still hold
instance Typeable1 Q
instance Typeable2 IOM

reader q = do
	   c1 <- qGetChar q
	   c2 <- qGetChar q
	   return [c1,c2]

test0 = withFile "/etc/motd" (const $ return True)

test1  = withFile "/etc/motd" reader
test1r = runIOM test1 >>= print

-- An attempt to leak a handle
-- test2 = runIOM (withFile "/etc/motd" (\q -> return q))
test3 = withFile "/etc/motd" (\q ->  (qGetChar q))

-- An attempt to leak a computation that uses the handle
-- test4 = withFile "/etc/motd" (\q ->  return (qGetChar q))

-- Dealing with two handles
-- Now we add the type signature, just to show that we can do that

reader2 :: Q mark -> Q mark -> IOM mark String
reader2 q1 q2 = do
	   c1 <- qGetChar q1
	   c2 <- qGetChar q2
	   return [c1,c2]


test5  = withFile "/etc/motd" (\q1 -> 
			      withFile "/etc/motd" (\q2 -> reader2 q1 q2))

test5r = runIOM test5 >>= print

-- An attempt to leak the handles.
{-
test6 = withFile "/etc/motd" 
	 (\q2 -> 
	  do
	  q' <- withFile "/etc/motd" (\q -> return q)
	  qGetChar q')


test7 = withFile "/etc/motd" 
	(\q2 -> 
	 do
	 q' <- withFile "/etc/motd" (\q -> return q2)
	 qGetChar q')
-}

{-
-- An attempt to leak computations involving handles
test8 = runIOM (withFile "/etc/motd" 
	 (\q2 -> 
	  do
	  a <- withFile "/etc/motd" (\q -> return (qGetChar q))
	  a))

test9 = withFile "/etc/motd" 
	 (\q2 -> 
	  do
	  a <- withFile "/etc/motd" (\q -> return (qGetChar q2))
	  a)

test9r = runIOM test9 >>= print
-}

-- An attempt to leak a computation that uses the handle, by Brandon Moore
test4' () = join $ withFile "/etc/motd" (\q ->  return (qGetChar q))
-- But we can't use test4':
-- test4'r = runIOM (test4' ())


-- Another test by Brandon Moore
-- Making sure runIOM can be used properly
-- testMinus1 = join $ runIOM $ withFile "/etc/motd" $ return . runIOM . qGetChar