[GHC] #9150: libraries/time: parseTime barfs on leading space in format string

[GHC]

#9150: libraries/time: parseTime barfs on leading space in format string
--------------------------+------------------------------------------------
       Reporter:  mjo     |             Owner:
           Type:  bug     |            Status:  new
       Priority:  normal  |         Milestone:
      Component:          |           Version:  7.8.2
  libraries (other)       |  Operating System:  Unknown/Multiple
       Keywords:          |   Type of failure:  Incorrect result at runtime
   Architecture:          |         Test Case:
  Unknown/Multiple        |          Blocking:
     Difficulty:          |
  Unknown                 |
     Blocked By:          |
Related Tickets:          |
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 This used to work around 1.4.0, one of my test suites caught it:

 {{{
 module Main
 where

 import Data.Time.Clock
 import Data.Time.Format
 import System.Locale

 main :: IO ()
 main = do
   putStrLn "Trailing space is handled:"
   print $ (parseTime defaultTimeLocale "%M " "15 " :: Maybe UTCTime)

   putStrLn "\nBut leading space isn't:"
   print $ (parseTime defaultTimeLocale " %M" " 15" :: Maybe UTCTime)
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9150>
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