pandoc/Setup.hs

import Distribution.Simple
import Distribution.Simple.Setup
    (copyDest, copyVerbosity, fromFlag, installVerbosity)
import Distribution.PackageDescription ( PackageDescription )
import Distribution.Simple.LocalBuildInfo
         ( LocalBuildInfo(..), absoluteInstallDirs )
import Distribution.Verbosity ( Verbosity )
import Distribution.Simple.InstallDirs (mandir, CopyDest (NoCopyDest))
import Distribution.Simple.Utils (copyFiles)
import Control.Exception ( bracket_ )
import Control.Monad ( unless )
import System.Process ( runCommand, runProcess, waitForProcess )
import System.FilePath ( (</>), (<.>) )
import System.Directory
import System.IO ( stderr, openTempFile )
import System.Exit
import System.Time
import System.IO.Error ( isDoesNotExistError )
import Data.Maybe ( fromJust, isNothing, catMaybes )
import Data.List ( isInfixOf )

main = do
  defaultMainWithHooks $ simpleUserHooks {
      runTests  = runTestSuite
    , postBuild = makeManPages
    , postCopy = \ _ flags pkg lbi -> installManpages pkg lbi
                    (fromFlag $ copyVerbosity flags)
                    (fromFlag $ copyDest flags)
    , postInst = \ _ flags pkg lbi -> installManpages pkg lbi
                    (fromFlag $ installVerbosity flags) NoCopyDest
    }
  exitWith ExitSuccess

-- | Run test suite.
runTestSuite _ _ _ _ = do
  tempPath <- catch getTemporaryDirectory (\_ -> return ".")
  (outputPath, hOut) <- openTempFile tempPath "out"
  runProcess "pandoc" ["--version"] Nothing Nothing Nothing (Just hOut) Nothing >>= waitForProcess
  output <- readFile outputPath
  let highlightingSupport = "with syntax highlighting" `isInfixOf` output
  let testArgs = if highlightingSupport then ["lhs"] else []
  let testCmd  = "runhaskell -i.. RunTests.hs " ++ unwords testArgs
  inDirectory "tests" $ runCommand testCmd >>= waitForProcess >>= exitWith

-- | Build man pages from markdown sources in man/man1/.
makeManPages _ _ _ _ = do
  mapM_ makeManPage manpages

manpages :: [FilePath]
manpages = ["pandoc.1", "hsmarkdown.1", "html2markdown.1", "markdown2pdf.1"]

manDir :: FilePath
manDir = "man" </> "man1"

-- | Build a man page from markdown source in man/man1.
makeManPage manpage = do
  let pandoc = "dist" </> "build" </> "pandoc" </> "pandoc"
  let page = manDir </> manpage
  let source = manDir </> manpage <.> "md"
  modifiedDeps <- modifiedDependencies page [source]
  unless (null modifiedDeps) $ do
    ec <- runProcess pandoc ["-s", "-S", "-r", "markdown", "-w", "man",
                "--template=templates/man.template", "-o", page, source]
                Nothing Nothing Nothing Nothing (Just stderr) >>= waitForProcess
    case ec of
         ExitSuccess -> putStrLn $ "Created " ++ manDir </> manpage
         _           -> do putStrLn $ "Error creating " ++ manDir </> manpage
                           exitWith ec

installManpages pkg lbi verbosity copy =
  mapM_ (installManpage pkg lbi verbosity copy) manpages

installManpage :: PackageDescription -> LocalBuildInfo
                  -> Verbosity -> CopyDest -> FilePath -> IO ()
installManpage pkg lbi verbosity copy manpage =
  copyFiles verbosity (mandir (absoluteInstallDirs pkg lbi copy) </> "man1")
             (zip (repeat manDir) manpages)

-- | Returns a list of 'dependencies' that have been modified after 'file'.
modifiedDependencies :: FilePath -> [FilePath] -> IO [FilePath]
modifiedDependencies file dependencies = do
  fileModTime <- catch (getModificationTime file) $
                 \e -> if isDoesNotExistError e
                          then return (TOD 0 0)   -- the minimum ClockTime
                          else ioError e
  depModTimes <- mapM getModificationTime dependencies
  let modified = zipWith (\dep time -> if time > fileModTime then Just dep else Nothing) dependencies depModTimes
  return $ catMaybes modified

-- | Perform an IO action in a directory.
inDirectory :: FilePath -> IO a -> IO a
inDirectory dir action = do
  oldDir <- getCurrentDirectory
  bracket_ (setCurrentDirectory dir) (setCurrentDirectory oldDir) action