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 qualified Data.FileEmbed as FileEmbed
import Data.List (inits,
intercalate)
import Data.Map (Map)
import qualified Data.Map as M
import Data.Maybe (fromMaybe)
import Data.Yaml (decodeEither)
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.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 $
[d </> configFileName | d <- ancestors current] ++
[configPath </> "config.yaml", home </> configFileName]
return mbConfig
where
ancestors :: FilePath -> [FilePath]
ancestors = init . map joinPath . reverse . inits . splitPath
search :: [FilePath] -> IO (Maybe FilePath)
search [] = return Nothing
search (f : fs) = do
exists <- doesFileExist f
verbose $ f ++ if exists then " exists" else " does not exist"
if exists then return (Just f) else search 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: " ++ err
Right config -> return config
parseConfig :: A.Value -> A.Parser Config
parseConfig (A.Object o) = do
config <- Config
<$> pure []
<*> (o A..:? "columns" A..!= 80)
<*> (o A..:? "language_extensions" A..!= [])
<*> (o A..:? "newline" >>= parseEnum newlines IO.nativeNewline)
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)
, ("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
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) <$> (o A..:? k)
parseImports :: Config -> A.Object -> A.Parser Step
parseImports config o = Imports.step
<$> pure (configColumns config)
<*> (Imports.Options
<$> (o A..:? "align" >>= parseEnum aligns (def Imports.importAlign))
<*> (o A..:? "list_align" >>= parseEnum listAligns (def Imports.listAlign))
<*> (o A..:? "pad_module_names" A..!= def Imports.padModuleNames)
<*> (o A..:? "long_list_align"
>>= parseEnum longListAligns (def Imports.longListAlign))
<*> (o A..:? "empty_list_align"
>>= parseEnum emptyListAligns (def Imports.emptyListAlign))
<*> o A..:? "list_padding" A..!= (def Imports.listPadding)
<*> o A..:? "separate_lists" A..!= (def Imports.separateLists)
<*> o A..:? "space_surround" A..!= (def Imports.spaceSurround))
where
def f = f Imports.defaultOptions
aligns =
[ ("global", Imports.Global)
, ("file", Imports.File)
, ("group", Imports.Group)
, ("none", Imports.None)
]
listAligns =
[ ("new_line", Imports.NewLine)
, ("with_alias", Imports.WithAlias)
, ("after_alias", Imports.AfterAlias)
]
longListAligns =
[ ("inline", Imports.Inline)
, ("new_line", Imports.InlineWithBreak)
, ("new_line_multiline", Imports.InlineToMultiline)
, ("multiline", Imports.Multiline)
]
emptyListAligns =
[ ("inherit", Imports.Inherit)
, ("right_after", Imports.RightAfter)
]
parseLanguagePragmas :: Config -> A.Object -> A.Parser Step
parseLanguagePragmas config o = LanguagePragmas.step
<$> 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