ghc-mod/Language/Haskell/GhcMod/Browse.hs
Daniel Gröber 82bb0090c0 Refactoring to use cabal-helper-wrapper
This turned out to be quite involved but save for this huge commit it's
actually quite awesome and squashes quite a few bugs and nasty
problems (hopefully). Most importantly we now have native cabal
component support without the user having to do anything to get it!

To do this we traverse imports starting from each component's
entrypoints (library modules or Main source file for executables) and
use this information to find which component's options each module will
build with. Under the assumption that these modules have to build with
every component they're used in we can now just pick one.

Quite a few internal assumptions have been invalidated by this
change. Most importantly the runGhcModT* family of cuntions now change
the current working directory to `cradleRootDir`.
2015-03-05 17:35:24 +01:00

151 lines
5.0 KiB
Haskell

module Language.Haskell.GhcMod.Browse (
browse
) where
import Control.Applicative ((<$>))
import Control.Exception (SomeException(..))
import Data.Char
import Data.List
import Data.Maybe
import FastString
import GHC
import qualified GHC as G
import Language.Haskell.GhcMod.Convert
import Language.Haskell.GhcMod.Doc (showPage, styleUnqualified)
import Language.Haskell.GhcMod.Gap as Gap
import Language.Haskell.GhcMod.Monad
import Language.Haskell.GhcMod.Types
import Name (getOccString)
import Outputable
import TyCon (isAlgTyCon)
import Type (dropForAlls, splitFunTy_maybe, mkFunTy, isPredTy)
import Exception (ExceptionMonad, ghandle)
----------------------------------------------------------------
-- | Getting functions, classes, etc from a module.
-- If 'detailed' is 'True', their types are also obtained.
-- If 'operators' is 'True', operators are also returned.
browse :: forall m. IOish m
=> ModuleString -- ^ A module name. (e.g. \"Data.List\")
-> GhcModT m String
browse pkgmdl = do
convert' . sort =<< go
where
-- TODO: Add API to Gm.Target to check if module is home module without
-- bringing up a GHC session as well then this can be made a lot cleaner
go = ghandle (\(SomeException _) -> return []) $ do
goPkgModule `G.gcatch` (\(SomeException _) -> goHomeModule)
goPkgModule = do
opt <- options
runGmPkgGhc $
processExports opt =<< tryModuleInfo =<< G.findModule mdlname mpkgid
goHomeModule = runGmLoadedT [Right mdlname] $ do
opt <- options
processExports opt =<< tryModuleInfo =<< G.findModule mdlname Nothing
tryModuleInfo m = fromJust <$> G.getModuleInfo m
(mpkg,mdl) = splitPkgMdl pkgmdl
mdlname = G.mkModuleName mdl
mpkgid = mkFastString <$> mpkg
-- |
--
-- >>> splitPkgMdl "base:Prelude"
-- (Just "base","Prelude")
-- >>> splitPkgMdl "Prelude"
-- (Nothing,"Prelude")
splitPkgMdl :: String -> (Maybe String,String)
splitPkgMdl pkgmdl = case break (==':') pkgmdl of
(mdl,"") -> (Nothing,mdl)
(pkg,_:mdl) -> (Just pkg,mdl)
-- Haskell 2010:
-- small -> ascSmall | uniSmall | _
-- ascSmall -> a | b | ... | z
-- uniSmall -> any Unicode lowercase letter
-- varid -> (small {small | large | digit | ' })
isNotOp :: String -> Bool
isNotOp (h:_) = isAlpha h || (h == '_')
isNotOp _ = error "isNotOp"
processExports :: (G.GhcMonad m, MonadIO m, ExceptionMonad m)
=> Options -> ModuleInfo -> m [String]
processExports opt minfo = do
let
removeOps
| operators opt = id
| otherwise = filter (isNotOp . getOccString)
mapM (showExport opt minfo) $ removeOps $ G.modInfoExports minfo
showExport :: forall m. (G.GhcMonad m, MonadIO m, ExceptionMonad m)
=> Options -> ModuleInfo -> Name -> m String
showExport opt minfo e = do
mtype' <- mtype
return $ concat $ catMaybes [mqualified, Just $ formatOp $ getOccString e, mtype']
where
mqualified = (G.moduleNameString (G.moduleName $ G.nameModule e) ++ ".") `justIf` qualified opt
mtype :: m (Maybe String)
mtype
| detailed opt = do
tyInfo <- G.modInfoLookupName minfo e
-- If nothing found, load dependent module and lookup global
tyResult <- maybe (inOtherModule e) (return . Just) tyInfo
dflag <- G.getSessionDynFlags
return $ do
typeName <- tyResult >>= showThing dflag
(" :: " ++ typeName) `justIf` detailed opt
| otherwise = return Nothing
formatOp nm
| null nm = error "formatOp"
| isNotOp nm = nm
| otherwise = "(" ++ nm ++ ")"
inOtherModule :: Name -> m (Maybe TyThing)
inOtherModule nm = do
G.getModuleInfo (G.nameModule nm) >> G.lookupGlobalName nm
justIf :: a -> Bool -> Maybe a
justIf x True = Just x
justIf _ False = Nothing
showThing :: DynFlags -> TyThing -> Maybe String
showThing dflag tything = showThing' dflag (fromTyThing tything)
showThing' :: DynFlags -> GapThing -> Maybe String
showThing' dflag (GtA a) = Just $ formatType dflag a
showThing' _ (GtT t) = unwords . toList <$> tyType t
where
toList t' = t' : getOccString t : map getOccString (G.tyConTyVars t)
showThing' _ _ = Nothing
formatType :: DynFlags -> Type -> String
formatType dflag a = showOutputable dflag (removeForAlls a)
tyType :: TyCon -> Maybe String
tyType typ
| isAlgTyCon typ
&& not (G.isNewTyCon typ)
&& not (G.isClassTyCon typ) = Just "data"
| G.isNewTyCon typ = Just "newtype"
| G.isClassTyCon typ = Just "class"
| Gap.isSynTyCon typ = Just "type"
| otherwise = Nothing
removeForAlls :: Type -> Type
removeForAlls ty = removeForAlls' ty' tty'
where
ty' = dropForAlls ty
tty' = splitFunTy_maybe ty'
removeForAlls' :: Type -> Maybe (Type, Type) -> Type
removeForAlls' ty Nothing = ty
removeForAlls' ty (Just (pre, ftype))
| isPredTy pre = mkFunTy pre (dropForAlls ftype)
| otherwise = ty
showOutputable :: Outputable a => DynFlags -> a -> String
showOutputable dflag = unwords . lines . showPage dflag styleUnqualified . ppr