Cabal/src/Distribution/Simple/GHC/EnvironmentParser.hs

   1 {-# LANGUAGE DeriveDataTypeable #-}
   2 {-# LANGUAGE FlexibleContexts #-}
   3 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
   4 {-# LANGUAGE LambdaCase #-}
   5 {-# LANGUAGE RankNTypes #-}
   6 {-# LANGUAGE RecordWildCards #-}
   7
   8 module Distribution.Simple.GHC.EnvironmentParser (parseGhcEnvironmentFile, readGhcEnvironmentFile, ParseErrorExc (..)) where
   9
  10 import Distribution.Compat.Prelude
  11 import Prelude ()
  12
  13 import Distribution.Simple.Compiler
  14 import Distribution.Simple.GHC.Internal
  15   ( GhcEnvironmentFileEntry (..)
  16   )
  17 import Distribution.Types.UnitId
  18   ( mkUnitId
  19   )
  20
  21 import qualified Text.Parsec as P
  22 import Text.Parsec.String
  23   ( Parser
  24   , parseFromFile
  25   )
  26
  27 parseEnvironmentFileLine :: Parser (GhcEnvironmentFileEntry FilePath)
  28 parseEnvironmentFileLine =
  29   GhcEnvFileComment <$> comment
  30     <|> GhcEnvFilePackageId <$> unitId
  31     <|> GhcEnvFilePackageDb <$> packageDb
  32     <|> pure GhcEnvFileClearPackageDbStack <* clearDb
  33   where
  34     comment = P.string "--" *> P.many (P.noneOf "\r\n")
  35     unitId =
  36       P.try $
  37         P.string "package-id"
  38           *> P.spaces
  39           *> (mkUnitId <$> P.many1 (P.satisfy $ \c -> isAlphaNum c || c `elem` "-_.+"))
  40     packageDb =
  41       (P.string "global-package-db" *> pure GlobalPackageDB)
  42         <|> (P.string "user-package-db" *> pure UserPackageDB)
  43         <|> (P.string "package-db" *> P.spaces *> (SpecificPackageDB <$> P.many1 (P.noneOf "\r\n") <* P.lookAhead P.endOfLine))
  44     clearDb = P.string "clear-package-db"
  45
  46 newtype ParseErrorExc = ParseErrorExc P.ParseError
  47   deriving (Show, Typeable)
  48
  49 instance Exception ParseErrorExc
  50
  51 parseGhcEnvironmentFile :: Parser [GhcEnvironmentFileEntry FilePath]
  52 parseGhcEnvironmentFile = parseEnvironmentFileLine `P.sepEndBy` P.endOfLine <* P.eof
  53
  54 readGhcEnvironmentFile :: FilePath -> IO [GhcEnvironmentFileEntry FilePath]
  55 readGhcEnvironmentFile path =
  56   either (throwIO . ParseErrorExc) return
  57     =<< parseFromFile parseGhcEnvironmentFile path