{-
Copyright (C) 2009 Ivan Lazar Miljenovic <Ivan.Miljenovic@gmail.com>
This file is part of SourceGraph.
SourceGraph is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-}
{- |
Module : CabalInfo
Description : Obtain information from a .cabal file.
Copyright : (c) Ivan Lazar Miljenovic 2009
License : GPL-3 or later.
Maintainer : Ivan.Miljenovic@gmail.com
Used to parse and obtain information from the provided Cabal file.
-}
module CabalInfo(parseCabal) where
import Distribution.Package
import Distribution.PackageDescription hiding (author)
import Distribution.PackageDescription.Parse
import Distribution.PackageDescription.Configuration
import Distribution.Compiler(CompilerId)
import Distribution.ModuleName(toFilePath)
import Distribution.Verbosity(silent)
import Distribution.Simple.Compiler(compilerId)
import Distribution.Simple.GHC(configure)
import Distribution.Simple.Program(defaultProgramConfiguration)
import Distribution.System(buildPlatform)
import Data.List(nub)
import Data.Maybe(isJust, fromJust)
import Control.Exception.Extensible(SomeException(..), try)
import Control.Monad(liftM)
import System.FilePath(dropExtension)
-- -----------------------------------------------------------------------------
ghcID :: IO CompilerId
ghcID = liftM (compilerId . fst)
$ configure silent Nothing Nothing defaultProgramConfiguration
parseCabal :: FilePath -> IO (Maybe (String, [FilePath]))
parseCabal fp = do cID <- ghcID
liftM (parseDesc cID) $ getDesc fp
where
-- Need to specify the Exception type
getDesc :: FilePath -> IO (Either SomeException GenericPackageDescription)
getDesc = try . readPackageDescription silent
parseDesc cID = fmap parse . compactEithers . fmap (unGeneric cID)
unGeneric cID = fmap fst
. finalizePackageDescription [] -- flags, use later
(const True) -- ignore
-- deps
buildPlatform
cID
[]
parse pd = (nm, exps)
where
nm = pName . pkgName $ package pd
pName (PackageName nm') = nm'
exes = executables pd
lib = library pd
moduleNames = map toFilePath
exps | not $ null exes = nub $ map (dropExtension . modulePath) exes
| isJust lib = moduleNames . exposedModules $ fromJust lib
| otherwise = error "No exposed modules"
compactEithers :: Either a (Either b c) -> Maybe c
compactEithers (Right (Right c)) = Just c
compactEithers _ = Nothing