{-# 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.ByteString.Lazy (fromStrict)
import Data.Char (toLower)
import qualified Data.FileEmbed as FileEmbed
import Data.List (intercalate,
nub)
import Data.Map (Map)
import qualified Data.Map as M
import Data.Maybe (fromMaybe)
import Data.YAML (prettyPosWithSource)
import Data.YAML.Aeson (decode1Strict)
import System.Directory
import System.FilePath ((</>))
import qualified System.IO as IO (Newline (..),
nativeNewline)
import qualified Language.Haskell.Stylish.Config.Cabal as Cabal
import Language.Haskell.Stylish.Config.Internal
import Language.Haskell.Stylish.Step
import qualified Language.Haskell.Stylish.Step.Data as Data
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]
, configIndent :: Int
, configColumns :: Maybe Int
, configLanguageExtensions :: [String]
, configNewline :: IO.Newline
, configCabal :: Bool
}
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
search verbose $
[d </> configFileName | d <- ancestors current] ++
[configPath </> "config.yaml", home </> configFileName]
search :: Verbose -> [FilePath] -> IO (Maybe FilePath)
search _ [] = return Nothing
search verbose (f : fs) = do
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 decode1Strict bytes of
Left (pos, err) -> error $ prettyPosWithSource pos (fromStrict bytes) ("Language.Haskell.Stylish.Config.loadConfig: " ++ err)
Right config -> do
cabalLanguageExtensions <- if configCabal config
then map show <$> Cabal.findLanguageExtensions verbose
else pure []
return $ config
{ configLanguageExtensions = nub $
configLanguageExtensions config ++ cabalLanguageExtensions
}
parseConfig :: A.Value -> A.Parser Config
parseConfig (A.Object o) = do
config <- Config
<$> pure []
<*> (o A..:? "indent" A..!= 4)
<*> (o A..:! "columns" A..!= Just 80)
<*> (o A..:? "language_extensions" A..!= [])
<*> (o A..:? "newline" >>= parseEnum newlines IO.nativeNewline)
<*> (o A..:? "cabal" A..!= True)
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)
, ("records", parseRecords)
, ("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
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) <$> (o A..:? k)
parseRecords :: Config -> A.Object -> A.Parser Step
parseRecords c _ = Data.step
<$> pure (configIndent c)
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))
<*> (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
<$> pure (configColumns config)
<*> (o A..:? "style" >>= parseEnum styles LanguagePragmas.Vertical)
<*> o A..:? "align" A..!= True
<*> o A..:? "remove_redundant" A..!= True
<*> mkLanguage o
where
styles =
[ ("vertical", LanguagePragmas.Vertical)
, ("compact", LanguagePragmas.Compact)
, ("compact_line", LanguagePragmas.CompactLine)
]
mkLanguage :: A.Object -> A.Parser String
mkLanguage o = do
lang <- o A..:? "language_prefix"
maybe (pure "LANGUAGE") validate lang
where
validate :: String -> A.Parser String
validate s
| fmap toLower s == "language" = pure s
| otherwise = fail "please provide a valid language prefix"
parseTabs :: Config -> A.Object -> A.Parser Step
parseTabs _ o = Tabs.step
<$> 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
<*> mkLanguage o