ghc-mod/Language/Haskell/GhcMod/Find.hs
2015-08-07 07:31:08 +02:00

146 lines
4.5 KiB
Haskell

{-# LANGUAGE CPP, BangPatterns, DoAndIfThenElse #-}
module Language.Haskell.GhcMod.Find
#ifndef SPEC
( Symbol
, SymbolDb
, loadSymbolDb
, lookupSymbol
, dumpSymbol
, findSymbol
, lookupSym
, isOutdated
)
#endif
where
import Control.Applicative
import Control.Monad (when, void)
import Data.Function (on)
import Data.List (groupBy, sort)
import qualified GHC as G
import Language.Haskell.GhcMod.Convert
import Language.Haskell.GhcMod.Gap (listVisibleModules)
import Language.Haskell.GhcMod.Monad
import Language.Haskell.GhcMod.PathsAndFiles
import Language.Haskell.GhcMod.Types
import Language.Haskell.GhcMod.Utils
import Language.Haskell.GhcMod.World (timedPackageCaches)
import Name (getOccString)
import Module (moduleName)
import System.Directory (doesFileExist, getModificationTime)
import System.FilePath ((</>))
import System.IO
import Prelude
import Data.Map (Map)
import qualified Data.Map as M
----------------------------------------------------------------
-- | Type of function and operation names.
type Symbol = String
-- | Database from 'Symbol' to \['ModuleString'\].
data SymbolDb = SymbolDb
{ table :: Map Symbol [ModuleString]
, symbolDbCachePath :: FilePath
} deriving (Show)
isOutdated :: IOish m => SymbolDb -> GhcModT m Bool
isOutdated db =
(liftIO . isOlderThan (symbolDbCachePath db)) =<< timedPackageCaches
----------------------------------------------------------------
-- | Looking up 'SymbolDb' with 'Symbol' to \['ModuleString'\]
-- which will be concatenated. 'loadSymbolDb' is called internally.
findSymbol :: IOish m => Symbol -> GhcModT m String
findSymbol sym = loadSymbolDb >>= lookupSymbol sym
-- | Looking up 'SymbolDb' with 'Symbol' to \['ModuleString'\]
-- which will be concatenated.
lookupSymbol :: IOish m => Symbol -> SymbolDb -> GhcModT m String
lookupSymbol sym db = convert' $ lookupSym sym db
lookupSym :: Symbol -> SymbolDb -> [ModuleString]
lookupSym sym db = M.findWithDefault [] sym $ table db
---------------------------------------------------------------
-- | Loading a file and creates 'SymbolDb'.
loadSymbolDb :: IOish m => GhcModT m SymbolDb
loadSymbolDb = do
ghcMod <- liftIO ghcModExecutable
tmpdir <- cradleTempDir <$> cradle
file <- liftIO $ chop <$> readProcess ghcMod ["dumpsym", tmpdir] ""
!db <- M.fromAscList . map conv . lines <$> liftIO (readFile file)
return $ SymbolDb
{ table = db
, symbolDbCachePath = file
}
where
conv :: String -> (Symbol, [ModuleString])
conv = read
chop :: String -> String
chop "" = ""
chop xs = init xs
----------------------------------------------------------------
-- used 'ghc-mod dumpsym'
-- | Dumping a set of ('Symbol',\['ModuleString'\]) to a file
-- if the file does not exist or is invalid.
-- The file name is printed.
dumpSymbol :: IOish m => FilePath -> GhcModT m String
dumpSymbol dir = do
create <- (liftIO . isOlderThan cache) =<< timedPackageCaches
runGmPkgGhc $ do
when create $
liftIO . writeSymbolCache cache =<< getGlobalSymbolTable
return $ unlines [cache]
where
cache = dir </> symbolCacheFile
writeSymbolCache :: FilePath
-> [(Symbol, [ModuleString])]
-> IO ()
writeSymbolCache cache sm =
void . withFile cache WriteMode $ \hdl ->
mapM (hPrint hdl) sm
-- | Check whether given file is older than any file from the given set.
-- Returns True if given file does not exist.
isOlderThan :: FilePath -> [TimedFile] -> IO Bool
isOlderThan cache files = do
exist <- doesFileExist cache
if not exist
then return True
else do
tCache <- getModificationTime cache
return $ any (tCache <=) $ map tfTime files -- including equal just in case
-- | Browsing all functions in all system modules.
getGlobalSymbolTable :: LightGhc [(Symbol, [ModuleString])]
getGlobalSymbolTable = do
df <- G.getSessionDynFlags
let mods = listVisibleModules df
moduleInfos <- mapM G.getModuleInfo mods
return $ collectModules
$ extractBindings `concatMap` (moduleInfos `zip` mods)
extractBindings :: (Maybe G.ModuleInfo, G.Module)
-> [(Symbol, ModuleString)]
extractBindings (Nothing, _) = []
extractBindings (Just inf, mdl) =
map (\name -> (getOccString name, modStr)) names
where
names = G.modInfoExports inf
modStr = ModuleString $ moduleNameString $ moduleName mdl
collectModules :: [(Symbol, ModuleString)]
-> [(Symbol, [ModuleString])]
collectModules = map tieup . groupBy ((==) `on` fst) . sort
where
tieup x = (head (map fst x), map snd x)