ghc-mod/Language/Haskell/GhcMod/CabalConfig.hs
2014-06-29 10:28:28 +02:00

120 lines
4.5 KiB
Haskell

{-# LANGUAGE CPP #-}
-- | Reading cabal @dist/setup-config@
module Language.Haskell.GhcMod.CabalConfig (
CabalConfig
, cabalConfigDependencies
) where
import Language.Haskell.GhcMod.GhcPkg
import Language.Haskell.GhcMod.Utils
import Language.Haskell.GhcMod.Read
import Language.Haskell.GhcMod.Types
import qualified Language.Haskell.GhcMod.Cabal16 as C16
import qualified Language.Haskell.GhcMod.Cabal18 as C18
import qualified Control.Exception as E
import Control.Applicative ((<$>))
import Control.Monad (mplus)
#if MIN_VERSION_mtl(2,2,1)
import Control.Monad.Except ()
#else
import Control.Monad.Error ()
#endif
import Data.Maybe ()
import Data.Set ()
import Data.List (find,tails,isPrefixOf,isInfixOf,nub,stripPrefix)
import Distribution.Package (InstalledPackageId(..)
, PackageIdentifier)
import Distribution.Simple.BuildPaths (defaultDistPref)
import Distribution.Simple.Configure (localBuildInfoFile)
import Distribution.Simple.LocalBuildInfo (ComponentName)
import System.FilePath ((</>))
----------------------------------------------------------------
type CabalConfig = String
-- | Get file containing 'LocalBuildInfo' data. If it doesn't exist run @cabal
-- configure@ i.e. configure with default options like @cabal build@ would do.
getConfig :: Cradle -> IO CabalConfig
getConfig cradle =
readFile path `E.catch` (\(E.SomeException _) -> configure >> readFile path)
where
prjDir = cradleRootDir cradle
path = prjDir </> configPath
configure =
withDirectory_ prjDir $ readProcess' "cabal" ["configure"]
-- | Path to 'LocalBuildInfo' file, usually @dist/setup-config@
configPath :: FilePath
configPath = localBuildInfoFile defaultDistPref
cabalConfigDependencies :: Cradle -> PackageIdentifier -> IO [Package]
cabalConfigDependencies cradle thisPkg =
configDependencies thisPkg <$> getConfig cradle
configDependencies :: PackageIdentifier -> CabalConfig -> [Package]
configDependencies thisPkg config = map fromInstalledPackageId deps
where
deps :: [InstalledPackageId]
deps = case (deps18 `mplus` deps16) of
Right ps -> ps
Left msg -> error msg
-- True if this dependency is an internal one (depends on the library
-- defined in the same package).
internal pkgid = pkgid == thisPkg
-- Cabal >= 1.18
deps18 :: Either String [InstalledPackageId]
deps18 =
map fst
<$> filterInternal
<$> (readEither =<< extractField config "componentsConfigs")
filterInternal
:: [(ComponentName, C18.ComponentLocalBuildInfo, [ComponentName])]
-> [(InstalledPackageId, PackageIdentifier)]
filterInternal ccfg = [ (ipkgid, pkgid)
| (_,clbi,_) <- ccfg
, (ipkgid, pkgid) <- C18.componentPackageDeps clbi
, not (internal pkgid) ]
-- Cabal 1.16 and below
deps16 :: Either String [InstalledPackageId]
deps16 = map fst <$> filter (not . internal . snd) . nub <$> do
cbi <- concat <$> sequence [ extract "executableConfigs"
, extract "testSuiteConfigs"
, extract "benchmarkConfigs" ]
:: Either String [(String, C16.ComponentLocalBuildInfo)]
return $ maybe [] C16.componentPackageDeps libraryConfig
++ concatMap (C16.componentPackageDeps . snd) cbi
where
libraryConfig :: Maybe C16.ComponentLocalBuildInfo
libraryConfig = do
field <- find ("libraryConfig" `isPrefixOf`) (tails config)
clbi <- stripPrefix " = " field
if "Nothing" `isPrefixOf` clbi
then Nothing
else case readMaybe =<< stripPrefix "Just " clbi of
Just x -> x
Nothing -> error $ "reading libraryConfig failed\n" ++ show (stripPrefix "Just " clbi)
extract :: String -> Either String [(String, C16.ComponentLocalBuildInfo)]
extract field = readConfigs field <$> extractField config field
readConfigs :: String -> String -> [(String, C16.ComponentLocalBuildInfo)]
readConfigs f s = case readEither s of
Right x -> x
Left msg -> error $ "reading config " ++ f ++ " failed ("++msg++")"
extractField :: CabalConfig -> String -> Either String String
extractField config field =
case extractParens <$> find (field `isPrefixOf`) (tails config) of
Just f -> Right f
Nothing -> Left $ "extractField: failed extracting "++field++" from input, input contained `"++field++"'? " ++ show (field `isInfixOf` config)