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|
--------------------------------------------------------------------------------
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TemplateHaskell #-}
module Language.Haskell.Stylish.Config
( Extensions
, Config (..)
, defaultConfigBytes
, configFilePath
, loadConfig
) where
--------------------------------------------------------------------------------
import Control.Monad (forM, mzero)
import Data.Aeson (FromJSON (..))
import qualified Data.Aeson as A
import qualified Data.Aeson.Types as A
import qualified Data.ByteString as B
import Data.Either (isRight)
import qualified Data.FileEmbed as FileEmbed
import Data.List (concatMap,
inits,
intercalate,
nub)
import Data.Map (Map)
import qualified Data.Map as M
import Data.Maybe (fromMaybe,
maybeToList)
import Data.Yaml (decodeEither',
prettyPrintParseException)
import qualified Distribution.PackageDescription as Cabal
import qualified Distribution.PackageDescription.Parsec as Cabal
import qualified Distribution.Simple.Utils as Cabal
import qualified Distribution.Types.CondTree as Cabal
import qualified Distribution.Verbosity as Cabal
import qualified Language.Haskell.Extension as Language
import System.Directory
import System.FilePath (joinPath,
splitPath,
(</>))
import qualified System.IO as IO (Newline (..),
nativeNewline)
--------------------------------------------------------------------------------
import Language.Haskell.Stylish.Step
import qualified Language.Haskell.Stylish.Step.Imports as Imports
import qualified Language.Haskell.Stylish.Step.LanguagePragmas as LanguagePragmas
import qualified Language.Haskell.Stylish.Step.SimpleAlign as SimpleAlign
import qualified Language.Haskell.Stylish.Step.Squash as Squash
import qualified Language.Haskell.Stylish.Step.Tabs as Tabs
import qualified Language.Haskell.Stylish.Step.TrailingWhitespace as TrailingWhitespace
import qualified Language.Haskell.Stylish.Step.UnicodeSyntax as UnicodeSyntax
import Language.Haskell.Stylish.Verbose
--------------------------------------------------------------------------------
type Extensions = [String]
--------------------------------------------------------------------------------
data Config = Config
{ configSteps :: [Step]
, configColumns :: Int
, configLanguageExtensions :: [String]
, configNewline :: IO.Newline
}
--------------------------------------------------------------------------------
instance FromJSON Config where
parseJSON = parseConfig
--------------------------------------------------------------------------------
configFileName :: String
configFileName = ".stylish-haskell.yaml"
--------------------------------------------------------------------------------
defaultConfigBytes :: B.ByteString
defaultConfigBytes = $(FileEmbed.embedFile "data/stylish-haskell.yaml")
--------------------------------------------------------------------------------
configFilePath :: Verbose -> Maybe FilePath -> IO (Maybe FilePath)
configFilePath _ (Just userSpecified) = return (Just userSpecified)
configFilePath verbose Nothing = do
current <- getCurrentDirectory
configPath <- getXdgDirectory XdgConfig "stylish-haskell"
home <- getHomeDirectory
mbConfig <- search verbose $
[d </> configFileName | d <- ancestors current] ++
[configPath </> "config.yaml", home </> configFileName]
return mbConfig
-- All ancestors of a dir (including that dir)
ancestors :: FilePath -> [FilePath]
ancestors = init . map joinPath . reverse . inits . splitPath
search :: Verbose -> [FilePath] -> IO (Maybe FilePath)
search _ [] = return Nothing
search verbose (f : fs) = do
-- TODO Maybe catch an error here, dir might be unreadable
exists <- doesFileExist f
verbose $ f ++ if exists then " exists" else " does not exist"
if exists then return (Just f) else search verbose fs
--------------------------------------------------------------------------------
loadConfig :: Verbose -> Maybe FilePath -> IO Config
loadConfig verbose userSpecified = do
mbFp <- configFilePath verbose userSpecified
verbose $ "Loading configuration at " ++ fromMaybe "<embedded>" mbFp
bytes <- maybe (return defaultConfigBytes) B.readFile mbFp
case decodeEither' bytes of
Left err -> error $
"Language.Haskell.Stylish.Config.loadConfig: " ++ prettyPrintParseException err
Right config -> do
mbCabalFile <- cabalFilePath verbose
exsFromCabal <- case mbCabalFile of
Just cabalFile -> map show <$>
readDefaultLanguageExtensions verbose cabalFile
Nothing -> return []
let exsFromConfig = configLanguageExtensions config
return $ config {configLanguageExtensions = nub (exsFromConfig <> exsFromCabal)}
--------------------------------------------------------------------------------
-- | Find the closest .cabal file, possibly going up the directory structure.
-- It's essential that
cabalFilePath :: Verbose -> IO (Maybe FilePath)
cabalFilePath verbose = do
potentialProjectRoots <- ancestors <$> getCurrentDirectory
potentialCabalFile <- filter isRight <$>
traverse Cabal.findPackageDesc potentialProjectRoots
case potentialCabalFile of
[Right cabalFile] -> return (Just cabalFile)
_ -> do
verbose $ ".cabal file not found, directories searched: " <>
show potentialProjectRoots
verbose $ "Stylish Haskell will work basing on LANGUAGE pragmas in source files."
return Nothing
--------------------------------------------------------------------------------
-- | Extract @default-extensions@ fields from a @.cabal@ file
readDefaultLanguageExtensions :: Verbose -> FilePath -> IO [Language.KnownExtension]
readDefaultLanguageExtensions verbose cabalFile = do
verbose $ "Parsing " <> cabalFile <> "..."
packageDescription <- Cabal.readGenericPackageDescription Cabal.silent cabalFile
let library :: [Cabal.Library]
library = maybeToList $ fst . Cabal.ignoreConditions <$>
Cabal.condLibrary packageDescription
subLibraries :: [Cabal.Library]
subLibraries = fst . Cabal.ignoreConditions . snd <$>
Cabal.condSubLibraries packageDescription
executables :: [Cabal.Executable]
executables = fst . Cabal.ignoreConditions . snd <$>
Cabal.condExecutables packageDescription
testSuites :: [Cabal.TestSuite]
testSuites = fst . Cabal.ignoreConditions . snd <$>
Cabal.condTestSuites packageDescription
benchmarks :: [Cabal.Benchmark]
benchmarks = fst . Cabal.ignoreConditions . snd <$>
Cabal.condBenchmarks packageDescription
gatherBuildInfos :: [Cabal.BuildInfo]
gatherBuildInfos = map Cabal.libBuildInfo library <>
map Cabal.libBuildInfo subLibraries <>
map Cabal.buildInfo executables <>
map Cabal.testBuildInfo testSuites <>
map Cabal.benchmarkBuildInfo benchmarks
defaultExtensions :: [Language.KnownExtension]
defaultExtensions = map fromEnabled . filter isEnabled $
concatMap Cabal.defaultExtensions gatherBuildInfos
where isEnabled (Language.EnableExtension _) = True
isEnabled _ = False
fromEnabled (Language.EnableExtension x) = x
fromEnabled x =
error $ "Language.Haskell.Stylish.Config.readLanguageExtensions: " <>
"invalid LANGUAGE pragma: " <> show x
verbose $ "Gathered default-extensions: " <> show defaultExtensions
pure $ nub defaultExtensions
--------------------------------------------------------------------------------
parseConfig :: A.Value -> A.Parser Config
parseConfig (A.Object o) = do
-- First load the config without the actual steps
config <- Config
<$> pure []
<*> (o A..:? "columns" A..!= 80)
<*> (o A..:? "language_extensions" A..!= [])
<*> (o A..:? "newline" >>= parseEnum newlines IO.nativeNewline)
-- Then fill in the steps based on the partial config we already have
stepValues <- o A..: "steps" :: A.Parser [A.Value]
steps <- mapM (parseSteps config) stepValues
return config {configSteps = concat steps}
where
newlines =
[ ("native", IO.nativeNewline)
, ("lf", IO.LF)
, ("crlf", IO.CRLF)
]
parseConfig _ = mzero
--------------------------------------------------------------------------------
catalog :: Map String (Config -> A.Object -> A.Parser Step)
catalog = M.fromList
[ ("imports", parseImports)
, ("language_pragmas", parseLanguagePragmas)
, ("simple_align", parseSimpleAlign)
, ("squash", parseSquash)
, ("tabs", parseTabs)
, ("trailing_whitespace", parseTrailingWhitespace)
, ("unicode_syntax", parseUnicodeSyntax)
]
--------------------------------------------------------------------------------
parseSteps :: Config -> A.Value -> A.Parser [Step]
parseSteps config val = do
map' <- parseJSON val :: A.Parser (Map String A.Value)
forM (M.toList map') $ \(k, v) -> case (M.lookup k catalog, v) of
(Just parser, A.Object o) -> parser config o
_ -> fail $ "Invalid declaration for " ++ k
--------------------------------------------------------------------------------
-- | Utility for enum-like options
parseEnum :: [(String, a)] -> a -> Maybe String -> A.Parser a
parseEnum _ def Nothing = return def
parseEnum strs _ (Just k) = case lookup k strs of
Just v -> return v
Nothing -> fail $ "Unknown option: " ++ k ++ ", should be one of: " ++
intercalate ", " (map fst strs)
--------------------------------------------------------------------------------
parseSimpleAlign :: Config -> A.Object -> A.Parser Step
parseSimpleAlign c o = SimpleAlign.step
<$> pure (configColumns c)
<*> (SimpleAlign.Config
<$> withDef SimpleAlign.cCases "cases"
<*> withDef SimpleAlign.cTopLevelPatterns "top_level_patterns"
<*> withDef SimpleAlign.cRecords "records")
where
withDef f k = fromMaybe (f SimpleAlign.defaultConfig) <$> (o A..:? k)
--------------------------------------------------------------------------------
parseSquash :: Config -> A.Object -> A.Parser Step
parseSquash _ _ = return Squash.step
--------------------------------------------------------------------------------
parseImports :: Config -> A.Object -> A.Parser Step
parseImports config o = Imports.step
<$> pure (configColumns config)
<*> (Imports.Options
<$> (o A..:? "align" >>= parseEnum aligns (def Imports.importAlign))
<*> (o A..:? "list_align" >>= parseEnum listAligns (def Imports.listAlign))
<*> (o A..:? "pad_module_names" A..!= def Imports.padModuleNames)
<*> (o A..:? "long_list_align"
>>= parseEnum longListAligns (def Imports.longListAlign))
-- Note that padding has to be at least 1. Default is 4.
<*> (o A..:? "empty_list_align"
>>= parseEnum emptyListAligns (def Imports.emptyListAlign))
<*> o A..:? "list_padding" A..!= (def Imports.listPadding)
<*> o A..:? "separate_lists" A..!= (def Imports.separateLists)
<*> o A..:? "space_surround" A..!= (def Imports.spaceSurround))
where
def f = f Imports.defaultOptions
aligns =
[ ("global", Imports.Global)
, ("file", Imports.File)
, ("group", Imports.Group)
, ("none", Imports.None)
]
listAligns =
[ ("new_line", Imports.NewLine)
, ("with_module_name", Imports.WithModuleName)
, ("with_alias", Imports.WithAlias)
, ("after_alias", Imports.AfterAlias)
]
longListAligns =
[ ("inline", Imports.Inline)
, ("new_line", Imports.InlineWithBreak)
, ("new_line_multiline", Imports.InlineToMultiline)
, ("multiline", Imports.Multiline)
]
emptyListAligns =
[ ("inherit", Imports.Inherit)
, ("right_after", Imports.RightAfter)
]
--------------------------------------------------------------------------------
parseLanguagePragmas :: Config -> A.Object -> A.Parser Step
parseLanguagePragmas config o = LanguagePragmas.step
<$> pure (configColumns config)
<*> (o A..:? "style" >>= parseEnum styles LanguagePragmas.Vertical)
<*> o A..:? "align" A..!= True
<*> o A..:? "remove_redundant" A..!= True
where
styles =
[ ("vertical", LanguagePragmas.Vertical)
, ("compact", LanguagePragmas.Compact)
, ("compact_line", LanguagePragmas.CompactLine)
]
--------------------------------------------------------------------------------
parseTabs :: Config -> A.Object -> A.Parser Step
parseTabs _ o = Tabs.step
<$> o A..:? "spaces" A..!= 8
--------------------------------------------------------------------------------
parseTrailingWhitespace :: Config -> A.Object -> A.Parser Step
parseTrailingWhitespace _ _ = return TrailingWhitespace.step
--------------------------------------------------------------------------------
parseUnicodeSyntax :: Config -> A.Object -> A.Parser Step
parseUnicodeSyntax _ o = UnicodeSyntax.step
<$> o A..:? "add_language_pragma" A..!= True
|