cabal-validate/src/ClockUtil.hs

   1 -- | Utilities for dealing with times and durations.
   2 module ClockUtil
   3   ( DiffTime
   4   , AbsoluteTime
   5   , diffAbsoluteTime
   6   , getAbsoluteTime
   7   , formatDiffTime
   8   ) where
   9
  10 import Data.Time.Clock (DiffTime, secondsToDiffTime)
  11 import Data.Time.Clock.System (getSystemTime, systemToTAITime)
  12 import Data.Time.Clock.TAI (AbsoluteTime, diffAbsoluteTime)
  13 import Data.Time.Format (defaultTimeLocale, formatTime)
  14
  15 -- | Get the current time as an `AbsoluteTime`.
  16 getAbsoluteTime :: IO AbsoluteTime
  17 getAbsoluteTime = systemToTAITime <$> getSystemTime
  18
  19 -- | Format a `DiffTime` nicely.
  20 --
  21 -- Short durations are formatted like @16.34s@, durations longer than a minute
  22 -- are formatted like @22:34.68@, durations longer than an hour are formatted
  23 -- like @1:32:04.68@.
  24 formatDiffTime :: DiffTime -> String
  25 formatDiffTime delta =
  26   let minute = secondsToDiffTime 60
  27       hour = 60 * minute
  28    in if delta >= hour
  29         then formatTime defaultTimeLocale "%h:%02M:%02ES" delta
  30         else
  31           if delta >= minute
  32             then formatTime defaultTimeLocale "%m:%2ES" delta
  33             else formatTime defaultTimeLocale "%2Ess" delta