{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE OverloadedStrings #-}
module Ormolu.Parser.Pragma
( Pragma (..),
parsePragma,
)
where
import Data.Char (isSpace)
import Data.Text (Text)
import qualified Data.Text as T
import qualified Data.Text.Encoding as T
import GHC.Data.FastString (bytesFS, mkFastString)
import GHC.Driver.Config.Parser (initParserOpts)
import GHC.DynFlags (baseDynFlags)
import qualified GHC.Parser.Lexer as L
import GHC.Types.SrcLoc
import Ormolu.Utils (textToStringBuffer)
data Pragma
=
PragmaLanguage [Text]
|
PragmaOptionsGHC Text
|
PragmaOptionsHaddock Text
deriving (Int -> Pragma -> ShowS
[Pragma] -> ShowS
Pragma -> String
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [Pragma] -> ShowS
$cshowList :: [Pragma] -> ShowS
show :: Pragma -> String
$cshow :: Pragma -> String
showsPrec :: Int -> Pragma -> ShowS
$cshowsPrec :: Int -> Pragma -> ShowS
Show, Pragma -> Pragma -> Bool
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: Pragma -> Pragma -> Bool
$c/= :: Pragma -> Pragma -> Bool
== :: Pragma -> Pragma -> Bool
$c== :: Pragma -> Pragma -> Bool
Eq)
parsePragma ::
Text ->
Maybe Pragma
parsePragma :: Text -> Maybe Pragma
parsePragma Text
input = do
Text
contents <- Text -> Text -> Maybe Text
T.stripSuffix Text
"#-}" forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< Text -> Text -> Maybe Text
T.stripPrefix Text
"{-#" Text
input
let (Text
pragmaName, Text
cs) = ((Char -> Bool) -> Text -> (Text, Text)
T.break Char -> Bool
isSpace forall b c a. (b -> c) -> (a -> b) -> a -> c
. (Char -> Bool) -> Text -> Text
T.dropWhile Char -> Bool
isSpace) Text
contents
case Text -> Text
T.toLower Text
pragmaName of
Text
"language" -> [Text] -> Pragma
PragmaLanguage forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> Text -> Maybe [Text]
parseExtensions Text
cs
Text
"options_ghc" -> forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ Text -> Pragma
PragmaOptionsGHC (Text -> Text
T.strip Text
cs)
Text
"options_haddock" -> forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ Text -> Pragma
PragmaOptionsHaddock (Text -> Text
T.strip Text
cs)
Text
_ -> forall a. Maybe a
Nothing
parseExtensions :: Text -> Maybe [Text]
parseExtensions :: Text -> Maybe [Text]
parseExtensions Text
str = Text -> Maybe [Token]
tokenize Text
str forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= [Token] -> Maybe [Text]
go
where
go :: [Token] -> Maybe [Text]
go = \case
[L.ITconid FastString
ext] -> forall (m :: * -> *) a. Monad m => a -> m a
return [FastString -> Text
fsToText FastString
ext]
(L.ITconid FastString
ext : Token
L.ITcomma : [Token]
xs) -> (FastString -> Text
fsToText FastString
ext forall a. a -> [a] -> [a]
:) forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> [Token] -> Maybe [Text]
go [Token]
xs
[Token]
_ -> forall a. Maybe a
Nothing
fsToText :: FastString -> Text
fsToText = ByteString -> Text
T.decodeUtf8 forall b c a. (b -> c) -> (a -> b) -> a -> c
. FastString -> ByteString
bytesFS
tokenize :: Text -> Maybe [L.Token]
tokenize :: Text -> Maybe [Token]
tokenize Text
input =
case forall a. P a -> PState -> ParseResult a
L.unP P [Token]
pLexer PState
parseState of
L.PFailed {} -> forall a. Maybe a
Nothing
L.POk PState
_ [Token]
x -> forall a. a -> Maybe a
Just [Token]
x
where
location :: RealSrcLoc
location = FastString -> Int -> Int -> RealSrcLoc
mkRealSrcLoc (String -> FastString
mkFastString String
"") Int
1 Int
1
buffer :: StringBuffer
buffer = Text -> StringBuffer
textToStringBuffer Text
input
parseState :: PState
parseState = ParserOpts -> StringBuffer -> RealSrcLoc -> PState
L.initParserState ParserOpts
parserOpts StringBuffer
buffer RealSrcLoc
location
parserOpts :: ParserOpts
parserOpts = DynFlags -> ParserOpts
initParserOpts DynFlags
baseDynFlags
pLexer :: L.P [L.Token]
pLexer :: P [Token]
pLexer = P [Token]
go
where
go :: P [Token]
go = do
Located Token
r <- forall a. Bool -> (Located Token -> P a) -> P a
L.lexer Bool
False forall (m :: * -> *) a. Monad m => a -> m a
return
case forall l e. GenLocated l e -> e
unLoc Located Token
r of
Token
L.ITeof -> forall (m :: * -> *) a. Monad m => a -> m a
return []
Token
x -> (Token
x forall a. a -> [a] -> [a]
:) forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> P [Token]
go