brittany/src-brittany/Main.hs

471 lines
19 KiB
Haskell

{-# LANGUAGE DataKinds #-}
module Main where
#include "prelude.inc"
-- brittany { lconfig_importAsColumn: 60, lconfig_importColumn: 60 }
import qualified Language.Haskell.GHC.ExactPrint as ExactPrint
import qualified Language.Haskell.GHC.ExactPrint.Annotate
as ExactPrint.Annotate
import qualified Language.Haskell.GHC.ExactPrint.Types as ExactPrint.Types
import qualified Language.Haskell.GHC.ExactPrint.Parsers as ExactPrint.Parsers
import qualified Data.Map as Map
import qualified Data.Monoid
import GHC ( GenLocated(L) )
import Outputable ( Outputable(..)
, showSDocUnsafe
)
import Text.Read ( Read(..) )
import qualified Text.ParserCombinators.ReadP as ReadP
import qualified Text.ParserCombinators.ReadPrec as ReadPrec
import qualified Data.Text.Lazy.Builder as Text.Builder
import Control.Monad ( zipWithM )
import Data.CZipWith
import qualified Debug.Trace as Trace
import Language.Haskell.Brittany.Internal.Types
import Language.Haskell.Brittany.Internal
import Language.Haskell.Brittany.Internal.Config
import Language.Haskell.Brittany.Internal.Config.Types
import Language.Haskell.Brittany.Internal.Utils
import Language.Haskell.Brittany.Internal.Obfuscation
import qualified Text.PrettyPrint as PP
import DataTreePrint
import UI.Butcher.Monadic
import qualified System.Exit
import qualified System.Directory as Directory
import qualified System.FilePath.Posix as FilePath
import qualified DynFlags as GHC
import qualified GHC.LanguageExtensions.Type as GHC
import Paths_brittany
data WriteMode = Display | Inplace
instance Read WriteMode where
readPrec = val "display" Display <|> val "inplace" Inplace
where val iden v = ReadPrec.lift $ ReadP.string iden >> return v
instance Show WriteMode where
show Display = "display"
show Inplace = "inplace"
main :: IO ()
main = mainFromCmdParserWithHelpDesc mainCmdParser
helpDoc :: PP.Doc
helpDoc = PP.vcat $ List.intersperse
(PP.text "")
[ parDocW
[ "Reformats one or more haskell modules."
, "Currently affects only the module head (imports/exports), type"
, "signatures and function bindings;"
, "everything else is left unmodified."
, "Based on ghc-exactprint, thus (theoretically) supporting all"
, "that ghc does."
]
, parDoc $ "Example invocations:"
, PP.hang (PP.text "") 2 $ PP.vcat
[ PP.text "brittany"
, PP.nest 2 $ PP.text "read from stdin, output to stdout"
]
, PP.hang (PP.text "") 2 $ PP.vcat
[ PP.text "brittany --indent=4 --write-mode=inplace *.hs"
, PP.nest 2 $ PP.vcat
[ PP.text "run on all modules in current directory (no backup!)"
, PP.text "4 spaces indentation"
]
]
, parDocW
[ "This program is written carefully and contains safeguards to ensure"
, "the output is syntactically valid and that no comments are removed."
, "Nonetheless, this is a young project, and there will always be bugs,"
, "and ensuring that the transformation never changes semantics of the"
, "transformed source is currently not possible."
, "Please do check the output and do not let brittany override your large"
, "codebase without having backups."
]
, parDoc $ "There is NO WARRANTY, to the extent permitted by law."
, parDocW
[ "This program is free software released under the AGPLv3."
, "For details use the --license flag."
]
, parDoc $ "See https://github.com/lspitzner/brittany"
, parDoc
$ "Please report bugs at"
++ " https://github.com/lspitzner/brittany/issues"
]
licenseDoc :: PP.Doc
licenseDoc = PP.vcat $ List.intersperse
(PP.text "")
[ parDoc $ "Copyright (C) 2016-2019 Lennart Spitzner"
, parDoc $ "Copyright (C) 2019 PRODA LTD"
, parDocW
[ "This program is free software: you can redistribute it and/or modify"
, "it under the terms of the GNU Affero General Public License,"
, "version 3, as published by the Free Software Foundation."
]
, parDocW
[ "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 Affero General Public License for more details."
]
, parDocW
[ "You should have received a copy of the GNU Affero General Public"
, "License along with this program. If not, see"
, "<http://www.gnu.org/licenses/>."
]
]
mainCmdParser :: CommandDesc () -> CmdParser Identity (IO ()) ()
mainCmdParser helpDesc = do
addCmdSynopsis "haskell source pretty printer"
addCmdHelp $ helpDoc
-- addCmd "debugArgs" $ do
addHelpCommand helpDesc
addCmd "license" $ addCmdImpl $ print $ licenseDoc
-- addButcherDebugCommand
reorderStart
printHelp <- addSimpleBoolFlag "h" ["help"] mempty
printVersion <- addSimpleBoolFlag "" ["version"] mempty
printLicense <- addSimpleBoolFlag "" ["license"] mempty
noUserConfig <- addSimpleBoolFlag "" ["no-user-config"] mempty
configPaths <- addFlagStringParams ""
["config-file"]
"PATH"
(flagHelpStr "path to config file") -- TODO: allow default on addFlagStringParam ?
cmdlineConfig <- cmdlineConfigParser
suppressOutput <- addSimpleBoolFlag
""
["suppress-output"]
(flagHelp $ parDoc
"suppress the regular output, i.e. the transformed haskell source"
)
_verbosity <- addSimpleCountFlag
"v"
["verbose"]
(flagHelp $ parDoc "[currently without effect; TODO]")
checkMode <- addSimpleBoolFlag
"c"
["check-mode"]
(flagHelp
(PP.vcat
[ PP.text "check for changes but do not write them out"
, PP.text "exits with code 0 if no changes necessary, 1 otherwise"
]
)
)
writeMode <- addFlagReadParam
""
["write-mode"]
"(display|inplace)"
( flagHelp
(PP.vcat
[ PP.text "display: output for any input(s) goes to stdout"
, PP.text "inplace: override respective input file (without backup!)"
]
)
Data.Monoid.<> flagDefault Display
)
inputParams <- addParamNoFlagStrings
"PATH"
(paramHelpStr "paths to input/inout haskell source files")
reorderStop
addCmdImpl $ void $ do
when printLicense $ do
print licenseDoc
System.Exit.exitSuccess
when printVersion $ do
do
putStrLn $ "brittany version " ++ showVersion version
putStrLn $ "Copyright (C) 2016-2019 Lennart Spitzner"
putStrLn $ "Copyright (C) 2019 PRODA LTD"
putStrLn $ "There is NO WARRANTY, to the extent permitted by law."
System.Exit.exitSuccess
when printHelp $ do
liftIO
$ putStrLn
$ PP.renderStyle PP.style { PP.ribbonsPerLine = 1.0 }
$ ppHelpShallow helpDesc
System.Exit.exitSuccess
let inputPaths =
if null inputParams then [Nothing] else map Just inputParams
let outputPaths = case writeMode of
Display -> repeat Nothing
Inplace -> inputPaths
configsToLoad <- liftIO $ if null configPaths
then
maybeToList <$> (Directory.getCurrentDirectory >>= findLocalConfigPath)
else pure configPaths
config <-
runMaybeT
(if noUserConfig
then readConfigs cmdlineConfig configsToLoad
else readConfigsWithUserConfig cmdlineConfig configsToLoad
)
>>= \case
Nothing -> System.Exit.exitWith (System.Exit.ExitFailure 53)
Just x -> return x
when (config & _conf_debug & _dconf_dump_config & confUnpack)
$ trace (showConfigYaml config)
$ return ()
results <- zipWithM
(coreIO putStrErrLn config (suppressOutput || checkMode))
inputPaths
outputPaths
if checkMode
then when (any (== Changes) (Data.Either.rights results))
$ System.Exit.exitWith (System.Exit.ExitFailure 1)
else case results of
xs | all Data.Either.isRight xs -> pure ()
[Left x] -> System.Exit.exitWith (System.Exit.ExitFailure x)
_ -> System.Exit.exitWith (System.Exit.ExitFailure 1)
data ChangeStatus = Changes | NoChanges
deriving (Eq)
-- | The main IO parts for the default mode of operation, and after commandline
-- and config stuff is processed.
coreIO
:: (String -> IO ()) -- ^ error output function. In parallel operation, you
-- may want serialize the different outputs and
-- consequently not directly print to stderr.
-> Config -- ^ global program config.
-> Bool -- ^ whether to supress output (to stdout). Purely IO flag, so
-- currently not part of program config.
-> Maybe FilePath.FilePath -- ^ input filepath; stdin if Nothing.
-> Maybe FilePath.FilePath -- ^ output filepath; stdout if Nothing.
-> IO (Either Int ChangeStatus) -- ^ Either an errorNo, or the change status.
coreIO putErrorLnIO config suppressOutput inputPathM outputPathM =
ExceptT.runExceptT $ do
let putErrorLn = liftIO . putErrorLnIO :: String -> ExceptT.ExceptT e IO ()
let ghcOptions = config & _conf_forward & _options_ghc & runIdentity
-- there is a good of code duplication between the following code and the
-- `pureModuleTransform` function. Unfortunately, there are also a good
-- amount of slight differences: This module is a bit more verbose, and
-- it tries to use the full-blown `parseModule` function which supports
-- CPP (but requires the input to be a file..).
let cppMode = config & _conf_preprocessor & _ppconf_CPPMode & confUnpack
-- the flag will do the following: insert a marker string
-- ("-- BRITANY_INCLUDE_HACK ") right before any lines starting with
-- "#include" before processing (parsing) input; and remove that marker
-- string from the transformation output.
-- The flag is intentionally misspelled to prevent clashing with
-- inline-config stuff.
let hackAroundIncludes =
config & _conf_preprocessor & _ppconf_hackAroundIncludes & confUnpack
let exactprintOnly = viaGlobal || viaDebug
where
viaGlobal = config & _conf_roundtrip_exactprint_only & confUnpack
viaDebug =
config & _conf_debug & _dconf_roundtrip_exactprint_only & confUnpack
let cppCheckFunc dynFlags = if GHC.xopt GHC.Cpp dynFlags
then case cppMode of
CPPModeAbort -> do
return $ Left "Encountered -XCPP. Aborting."
CPPModeWarn -> do
putErrorLnIO
$ "Warning: Encountered -XCPP."
++ " Be warned that -XCPP is not supported and that"
++ " brittany cannot check that its output is syntactically"
++ " valid in its presence."
return $ Right True
CPPModeNowarn -> return $ Right True
else return $ Right False
(parseResult, originalContents) <- case inputPathM of
Nothing -> do
-- TODO: refactor this hack to not be mixed into parsing logic
let hackF s = if "#include" `isPrefixOf` s
then "-- BRITANY_INCLUDE_HACK " ++ s
else s
let hackTransform = if hackAroundIncludes && not exactprintOnly
then List.intercalate "\n" . fmap hackF . lines'
else id
inputString <- liftIO $ System.IO.hGetContents System.IO.stdin
parseRes <- liftIO $ parseModuleFromString ghcOptions
"stdin"
cppCheckFunc
(hackTransform inputString)
return (parseRes, Text.pack inputString)
Just p -> liftIO $ do
parseRes <- parseModule ghcOptions p cppCheckFunc
inputText <- Text.IO.readFile p
-- The above means we read the file twice, but the
-- GHC API does not really expose the source it
-- read. Should be in cache still anyways.
--
-- We do not use TextL.IO.readFile because lazy IO is evil.
-- (not identical -> read is not finished ->
-- handle still open -> write below crashes - evil.)
return (parseRes, inputText)
case parseResult of
Left left -> do
putErrorLn "parse error:"
putErrorLn left
ExceptT.throwE 60
Right (anns, parsedSource, hasCPP) -> do
(inlineConf, perItemConf) <-
case
extractCommentConfigs anns (getTopLevelDeclNameMap parsedSource)
of
Left (err, input) -> do
putErrorLn $ "Error: parse error in inline configuration:"
putErrorLn err
putErrorLn $ " in the string \"" ++ input ++ "\"."
ExceptT.throwE 61
Right c -> -- trace (showTree c) $
pure c
let moduleConf = cZipWith fromOptionIdentity config inlineConf
when (config & _conf_debug & _dconf_dump_ast_full & confUnpack) $ do
let val = printTreeWithCustom 100 (customLayouterF anns) parsedSource
trace ("---- ast ----\n" ++ show val) $ return ()
(errsWarns, outSText) <- do
if exactprintOnly
then do
pure ([], Text.pack $ ExactPrint.exactPrint parsedSource anns)
else do
let omitCheck =
moduleConf
& _conf_errorHandling
.> _econf_omit_output_valid_check
.> confUnpack
(ews, outRaw) <- if hasCPP || omitCheck
then return
$ pPrintModule moduleConf perItemConf anns parsedSource
else liftIO $ pPrintModuleAndCheck moduleConf
perItemConf
anns
parsedSource
let hackF s = fromMaybe s $ TextL.stripPrefix
(TextL.pack "-- BRITANY_INCLUDE_HACK ")
s
let out = TextL.toStrict $ if hackAroundIncludes
then
TextL.intercalate (TextL.pack "\n")
$ fmap hackF
$ TextL.splitOn (TextL.pack "\n") outRaw
else outRaw
out' <- if moduleConf & _conf_obfuscate & confUnpack
then lift $ obfuscate out
else pure out
pure $ (ews, out')
let customErrOrder ErrorInput{} = 4
customErrOrder LayoutWarning{} = -1 :: Int
customErrOrder ErrorOutputCheck{} = 1
customErrOrder ErrorUnusedComment{} = 2
customErrOrder ErrorUnknownNode{} = -2 :: Int
customErrOrder ErrorMacroConfig{} = 5
when (not $ null errsWarns) $ do
let groupedErrsWarns =
Data.List.Extra.groupOn customErrOrder
$ List.sortOn customErrOrder
$ errsWarns
groupedErrsWarns `forM_` \case
(ErrorOutputCheck{} : _) -> do
putErrorLn
$ "ERROR: brittany pretty printer"
++ " returned syntactically invalid result."
(ErrorInput str : _) -> do
putErrorLn $ "ERROR: parse error: " ++ str
uns@(ErrorUnknownNode{} : _) -> do
putErrorLn $ "WARNING: encountered unknown syntactical constructs:"
uns `forM_` \case
ErrorUnknownNode str ast@(L loc _) -> do
putErrorLn $ " " <> str <> " at " <> showSDocUnsafe (ppr loc)
when
( config
& _conf_debug
& _dconf_dump_ast_unknown
& confUnpack
)
$ do
putErrorLn $ " " ++ show (astToDoc ast)
_ -> error "cannot happen (TM)"
putErrorLn " -> falling back on exactprint for this element of the module"
warns@(LayoutWarning{} : _) -> do
putErrorLn $ "WARNINGS:"
warns `forM_` \case
LayoutWarning str -> putErrorLn str
_ -> error "cannot happen (TM)"
unused@(ErrorUnusedComment{} : _) -> do
putErrorLn
$ "Error: detected unprocessed comments."
++ " The transformation output will most likely"
++ " not contain some of the comments"
++ " present in the input haskell source file."
putErrorLn $ "Affected are the following comments:"
unused `forM_` \case
ErrorUnusedComment str -> putErrorLn str
_ -> error "cannot happen (TM)"
(ErrorMacroConfig err input : _) -> do
putErrorLn $ "Error: parse error in inline configuration:"
putErrorLn err
putErrorLn $ " in the string \"" ++ input ++ "\"."
[] -> error "cannot happen"
-- TODO: don't output anything when there are errors unless user
-- adds some override?
let
hasErrors =
case config & _conf_errorHandling & _econf_Werror & confUnpack of
False -> 0 < maximum (-1 : fmap customErrOrder errsWarns)
True -> not $ null errsWarns
outputOnErrs =
config
& _conf_errorHandling
& _econf_produceOutputOnErrors
& confUnpack
shouldOutput = not suppressOutput && (not hasErrors || outputOnErrs)
let noChanges = outSText == originalContents
when shouldOutput
$ addTraceSep (_conf_debug config)
$ case outputPathM of
Nothing -> liftIO $ Text.IO.putStr $ outSText
Just p -> liftIO $ do
let isIdentical = case inputPathM of
Nothing -> False
Just _ -> noChanges
unless isIdentical $ Text.IO.writeFile p $ outSText
when hasErrors $ ExceptT.throwE 70
return (if noChanges then NoChanges else Changes)
where
addTraceSep conf =
if or
[ confUnpack $ _dconf_dump_annotations conf
, confUnpack $ _dconf_dump_ast_unknown conf
, confUnpack $ _dconf_dump_ast_full conf
, confUnpack $ _dconf_dump_bridoc_raw conf
, confUnpack $ _dconf_dump_bridoc_simpl_alt conf
, confUnpack $ _dconf_dump_bridoc_simpl_floating conf
, confUnpack $ _dconf_dump_bridoc_simpl_columns conf
, confUnpack $ _dconf_dump_bridoc_simpl_indent conf
, confUnpack $ _dconf_dump_bridoc_final conf
]
then trace "----"
else id