Check.hs

{-# LANGUAGE PatternGuards #-}

module HsDev.Tools.Ghc.Check (
	checkFiles, check, checkFile, checkSource,

	Ghc,
	module HsDev.Tools.Types,
	module HsDev.Symbols.Types,
	Cabal(..), Project(..),

	module Control.Monad.Except
	) where

import Control.Lens (preview, view, each, _Just, (^..))
import Control.Monad.Except
import Control.Concurrent.FiniteChan
import Data.Maybe (fromMaybe, mapMaybe)
import Data.Version (showVersion)
import Data.Time.Clock (getCurrentTime)
import HsDev.Tools.Ghc.Worker
import System.FilePath (makeRelative)
import System.Directory (doesDirectoryExist)
import Text.Read (readMaybe)

import GHC hiding (Warning, Module, moduleName)
import Outputable
import qualified Packages as GHC
import StringBuffer (stringToStringBuffer)
import FastString (unpackFS)
import qualified ErrUtils as E

import HsDev.Symbols (Canonicalize(..), moduleOpts)
import HsDev.Symbols.Location
import HsDev.Symbols.Types
import HsDev.Tools.Base
import HsDev.Tools.Types
import HsDev.Util (readFileUtf8, ordNub)

-- | Check files and collect warnings and errors
checkFiles :: [String] -> Cabal -> [FilePath] -> Maybe Project -> Ghc [Note OutputMessage]
checkFiles opts cabal files _ = do
	ch <- liftIO newChan
	withFlags $ do
		modifyFlags (\fs -> fs { log_action = logAction ch })
		_ <- addCmdOpts ("-Wall" : (cabalOpt cabal ++ opts))
		clearTargets
		mapM (`makeTarget` Nothing) files >>= loadTargets
	notes <- liftIO $ stopChan ch
	liftIO $ recalcNotesTabs notes

-- | Check module source
check :: [String] -> Cabal -> Module -> Maybe String -> ExceptT String Ghc [Note OutputMessage]
check opts cabal m msrc = case view moduleLocation m of
	FileModule file proj -> do
		ch <- liftIO newChan
		pkgs <- lift listPackages
		let
			dir = fromMaybe
				(sourceModuleRoot (view moduleName m) file) $
				preview (_Just . projectPath) proj
		dirExist <- liftIO $ doesDirectoryExist dir
		lift $ withFlags $ (if dirExist then withCurrentDirectory dir else id) $ do
			modifyFlags (\fs -> fs { log_action = logAction ch })
			_ <- addCmdOpts $ concat [
				["-Wall"],
				cabalOpt cabal,
				moduleOpts pkgs m,
				opts]
			tm <- liftIO getCurrentTime
			clearTargets
			target <- makeTarget (makeRelative dir file) msrc
			loadTargets [target]
		notes <- liftIO $ stopChan ch
		liftIO $ recalcNotesTabs notes
	_ -> throwError "Module is not source"

-- | Check module and collect warnings and errors
checkFile :: [String] -> Cabal -> Module -> ExceptT String Ghc [Note OutputMessage]
checkFile opts cabal m = check opts cabal m Nothing

-- | Check module and collect warnings and errors
checkSource :: [String] -> Cabal -> Module -> String -> ExceptT String Ghc [Note OutputMessage]
checkSource opts cabal m src = check opts cabal m (Just src)

-- | Log  ghc warnings and errors as to chan
-- You may have to apply recalcTabs on result notes
logAction :: Chan (Note OutputMessage) -> DynFlags -> E.Severity -> SrcSpan -> PprStyle -> SDoc -> IO ()
logAction ch fs sev src _ msg
	| Just sev' <- checkSev sev = do
		src' <- canonicalize srcMod
		putChan ch $ Note {
			_noteSource = src',
			_noteRegion = spanRegion src,
			_noteLevel = Just sev',
			_note = OutputMessage {
				_message = showSDoc fs msg,
				_messageSuggestion = Nothing } }
	| otherwise = return ()
	where
		checkSev SevWarning = Just Warning
		checkSev SevError = Just Error
		checkSev SevFatal = Just Error
		checkSev _ = Nothing
		srcMod = case src of
			RealSrcSpan s' -> FileModule (unpackFS $ srcSpanFile s') Nothing
			_ -> ModuleSource Nothing

-- Recalc tabs for notes
recalcNotesTabs :: [Note OutputMessage] -> IO [Note OutputMessage]
recalcNotesTabs notes = do
	cts <- mapM readFileUtf8 files
	let
		recalc' n = fromMaybe n $ do
			fname <- preview (noteSource . moduleFile) n
			cts' <- lookup fname (zip files cts)
			return $ recalcTabs cts' 8 n
	return $ map recalc' notes
	where
		files = ordNub $ notes ^.. each . noteSource . moduleFile