module Cabal2nix
( main, cabal2nix
)
where
import Control.Exception ( bracket )
import Control.Lens
import Data.Maybe ( fromMaybe )
import Data.Monoid ( (<>) )
import qualified Data.Set as Set
import Data.String
import qualified Distribution.Compat.ReadP as P
import Distribution.Compiler
import Distribution.Nixpkgs.Fetch
import Distribution.Nixpkgs.Haskell
import Distribution.Nixpkgs.Haskell.FromCabal
import Distribution.Nixpkgs.Haskell.PackageSourceSpec
import Distribution.Nixpkgs.Meta
import Distribution.PackageDescription ( FlagName(..), FlagAssignment )
import Distribution.Simple.Utils ( lowercase )
import Distribution.System
import Distribution.Text
import Language.Nix
import Options.Applicative
import Paths_cabal2nix ( version )
import System.Environment ( getArgs )
import System.IO ( hFlush, stdout, stderr )
import qualified Text.PrettyPrint.ANSI.Leijen as P2 hiding ( (<$>), (<>) )
import Text.PrettyPrint.HughesPJClass ( Doc, Pretty(..), text, vcat, hcat, semi )
data Options = Options
{ optSha256 :: Maybe String
, optMaintainer :: [String]
, optHaddock :: Bool
, optDoCheck :: Bool
, optJailbreak :: Bool
, optRevision :: Maybe String
, optHyperlinkSource :: Bool
, optEnableLibraryProfiling :: Bool
, optEnableExecutableProfiling :: Bool
, optEnableProfiling :: Maybe Bool
, optExtraArgs :: [String]
, optHackageDb :: Maybe FilePath
, optNixShellOutput :: Bool
, optFlags :: [String]
, optCompiler :: CompilerId
, optSystem :: Platform
, optSubpath :: Maybe FilePath
, optUrl :: String
}
deriving (Show)
options :: Parser Options
options = Options
<$> optional (strOption $ long "sha256" <> metavar "HASH" <> help "sha256 hash of source tarball")
<*> many (strOption $ long "maintainer" <> metavar "MAINTAINER" <> help "maintainer of this package (may be specified multiple times)")
<*> flag True False (long "no-haddock" <> help "don't run Haddock when building this package")
<*> flag True False (long "no-check" <> help "don't run regression test suites of this package")
<*> switch (long "jailbreak" <> help "disregard version restrictions on build inputs")
<*> optional (strOption $ long "revision" <> help "revision to use when fetching from VCS")
<*> flag True False (long "no-hyperlink-source" <> help "don't generate pretty-printed source code for the documentation")
<*> switch (long "enable-library-profiling" <> help "enable library profiling in the generated build")
<*> switch (long "enable-executable-profiling" <> help "enable executable profiling in the generated build")
<*> optional (switch (long "enable-profiling" <> help "enable both library and executable profiling in the generated build"))
<*> many (strOption $ long "extra-arguments" <> help "extra parameters required for the function body")
<*> optional (strOption $ long "hackage-db" <> metavar "PATH" <> help "path to the local hackage db in tar format")
<*> switch (long "shell" <> help "generate output suitable for nix-shell")
<*> many (strOption $ short 'f' <> long "flag" <> help "Cabal flag (may be specified multiple times)")
<*> option (readP parse) (long "compiler" <> help "compiler to use when evaluating the Cabal file" <> value buildCompilerId <> showDefaultWith display)
<*> option (readP parsePlatform) (long "system" <> help "target system to use when evaluating the Cabal file" <> value buildPlatform <> showDefaultWith display)
<*> optional (strOption $ long "subpath" <> metavar "PATH" <> help "Path to Cabal file's directory relative to the URI (default is root directory)")
<*> strArgument (metavar "URI")
readP :: P.ReadP a a -> ReadM a
readP p = eitherReader $ \s -> case [ r' | (r',"") <- P.readP_to_S p s ] of
(r:_) -> Right r
_ -> Left ("invalid value " ++ show s)
parsePlatform :: P.ReadP r Platform
parsePlatform = do arch <- P.choice [P.string "i686" >> return I386, P.string "x86_64" >> return X86_64]
_ <- P.char '-'
os <- P.choice [P.string "linux" >> return Linux, P.string "darwin" >> return OSX]
return (Platform arch os)
pinfo :: ParserInfo Options
pinfo = info
( helper
<*> infoOption ("cabal2nix " ++ display version) (long "version" <> help "Show version number")
<*> options
)
( fullDesc
<> header "cabal2nix converts Cabal files into build instructions for Nix."
<> progDescDoc (Just (P2.vcat
[ P2.text ""
, P2.text "Recognized URI schemes:"
, P2.text ""
, P2.text " cabal://pkgname-pkgversion download the specified package from Hackage"
, P2.text " cabal://pkgname download latest version of this package from Hackage"
, P2.text " file:///local/path load the Cabal file from the local disk"
, P2.text " /local/path abbreviated version of file URI"
, P2.text " <git/svn/bzr/hg URL> download the source from the specified repository"
, P2.text ""
, P2.fillSep (map P2.text (words ( "If the URI refers to a cabal file, information for building the package "
++ "will be retrieved from that file, but hackage will be used as a source "
++ "for the derivation. Otherwise, the supplied URI will be used to as the "
++ "souce for the derivation and the information is taken from the cabal file "
++ "at the root of the downloaded source."
)))
]))
)
main :: IO ()
main = bracket (return ()) (\() -> hFlush stdout >> hFlush stderr) $ \() ->
cabal2nix =<< getArgs
cabal2nix :: [String] -> IO ()
cabal2nix args = do
Options {..} <- handleParseResult $ execParserPure defaultPrefs pinfo args
pkg <- getPackage optHackageDb $ Source optUrl (fromMaybe "" optRevision) (maybe UnknownHash Guess optSha256) (fromMaybe "" optSubpath)
let
deriv :: Derivation
deriv = fromGenericPackageDescription (const True)
(\i -> Just (binding # (i, path # [i])))
optSystem
(unknownCompilerInfo optCompiler NoAbiTag)
(readFlagList optFlags)
[]
(pkgCabal pkg)
& src .~ pkgSource pkg
& subpath .~ (fromMaybe "." optSubpath)
& runHaddock .~ optHaddock
& jailbreak .~ optJailbreak
& hyperlinkSource .~ optHyperlinkSource
& enableLibraryProfiling .~ (fromMaybe False optEnableProfiling || optEnableLibraryProfiling)
& enableExecutableProfiling .~ (fromMaybe False optEnableProfiling || optEnableExecutableProfiling)
& metaSection.maintainers .~ Set.fromList (map (review ident) optMaintainer)
& doCheck &&~ optDoCheck
& extraFunctionArgs %~ Set.union (Set.fromList ("inherit stdenv":map (fromString . ("inherit " ++)) optExtraArgs))
shell :: Doc
shell = vcat
[ text "{ nixpkgs ? import <nixpkgs> {}, compiler ? \"default\" }:"
, text ""
, text "let"
, text ""
, text " inherit (nixpkgs) pkgs;"
, text ""
, hcat [ text " f = ", pPrint deriv, semi ]
, text ""
, text " haskellPackages = if compiler == \"default\""
, text " then pkgs.haskellPackages"
, text " else pkgs.haskell.packages.${compiler};"
, text ""
, text " drv = haskellPackages.callPackage f {};"
, text ""
, text "in"
, text ""
, text " if pkgs.lib.inNixShell then drv.env else drv"
]
print (if optNixShellOutput then shell else pPrint deriv)
readFlagList :: [String] -> FlagAssignment
readFlagList = map tagWithValue
where tagWithValue ('-':fname) = (FlagName (lowercase fname), False)
tagWithValue fname = (FlagName (lowercase fname), True)