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
|
module Test.Framework.Runners.TimedConsumption (
consumeListInInterval
) where
import Test.Framework.Utilities
import System.CPUTime
-- | Evaluates the given list for the given number of microseconds. After the time limit
-- has been reached, a list is returned consisting of the prefix of the list that was
-- successfully evaluated within the time limit.
--
-- This function does /not/ evaluate the elements of the list: it just ensures that the
-- list spine arrives in good order.
--
-- The spine of the list is evaluated on the current thread, so if spine evaluation blocks
-- this function will also block, potentially for longer than the specificed delay.
consumeListInInterval :: Int -> [a] -> IO [a]
consumeListInInterval delay list = do
initial_time_ps <- getCPUTime
go initial_time_ps (microsecondsToPicoseconds (fromIntegral delay)) list
where
go _ _ [] = return []
go initial_time_ps delay_ps (x:xs) = do
this_time <- getCPUTime
if this_time - initial_time_ps < delay_ps
then go initial_time_ps delay_ps xs >>= return . (x:)
else return []
|
