hackport-0.4.7: cabal/cabal-install/Distribution/Client/Init.hs
{-# LANGUAGE CPP #-}
-----------------------------------------------------------------------------
-- |
-- Module : Distribution.Client.Init
-- Copyright : (c) Brent Yorgey 2009
-- License : BSD-like
--
-- Maintainer : cabal-devel@haskell.org
-- Stability : provisional
-- Portability : portable
--
-- Implementation of the 'cabal init' command, which creates an initial .cabal
-- file for a project.
--
-----------------------------------------------------------------------------
module Distribution.Client.Init (
-- * Commands
initCabal
) where
import System.IO
( hSetBuffering, stdout, BufferMode(..) )
import System.Directory
( getCurrentDirectory, doesDirectoryExist, doesFileExist, copyFile
, getDirectoryContents, createDirectoryIfMissing )
import System.FilePath
( (</>), (<.>), takeBaseName )
import Data.Time
( getCurrentTime, utcToLocalTime, toGregorian, localDay, getCurrentTimeZone )
import Data.Char
( toUpper )
import Data.List
( intercalate, nub, groupBy, (\\) )
import Data.Maybe
( fromMaybe, isJust, catMaybes, listToMaybe )
import Data.Function
( on )
import qualified Data.Map as M
#if !MIN_VERSION_base(4,8,0)
import Control.Applicative
( (<$>) )
import Data.Traversable
( traverse )
#endif
import Control.Monad
( when, unless, (>=>), join, forM_ )
import Control.Arrow
( (&&&), (***) )
import Text.PrettyPrint hiding (mode, cat)
import Data.Version
( Version(..) )
import Distribution.Version
( orLaterVersion, earlierVersion, intersectVersionRanges, VersionRange )
import Distribution.Verbosity
( Verbosity )
import Distribution.ModuleName
( ModuleName, fromString ) -- And for the Text instance
import Distribution.InstalledPackageInfo
( InstalledPackageInfo, sourcePackageId, exposed )
import qualified Distribution.Package as P
import Language.Haskell.Extension ( Language(..) )
import Distribution.Client.Init.Types
( InitFlags(..), PackageType(..), Category(..) )
import Distribution.Client.Init.Licenses
( bsd2, bsd3, gplv2, gplv3, lgpl21, lgpl3, agplv3, apache20, mit, mpl20, isc )
import Distribution.Client.Init.Heuristics
( guessPackageName, guessAuthorNameMail, guessMainFileCandidates,
SourceFileEntry(..),
scanForModules, neededBuildPrograms )
import Distribution.License
( License(..), knownLicenses )
import Distribution.ReadE
( runReadE, readP_to_E )
import Distribution.Simple.Setup
( Flag(..), flagToMaybe )
import Distribution.Simple.Configure
( getInstalledPackages )
import Distribution.Simple.Compiler
( PackageDBStack, Compiler )
import Distribution.Simple.Program
( ProgramConfiguration )
import Distribution.Simple.PackageIndex
( InstalledPackageIndex, moduleNameIndex )
import Distribution.Text
( display, Text(..) )
import Distribution.Client.PackageIndex
( elemByPackageName )
import Distribution.Client.IndexUtils
( getSourcePackages )
import Distribution.Client.Types
( SourcePackageDb(..), Repo )
initCabal :: Verbosity
-> PackageDBStack
-> [Repo]
-> Compiler
-> ProgramConfiguration
-> InitFlags
-> IO ()
initCabal verbosity packageDBs repos comp conf initFlags = do
installedPkgIndex <- getInstalledPackages verbosity comp packageDBs conf
sourcePkgDb <- getSourcePackages verbosity repos
hSetBuffering stdout NoBuffering
initFlags' <- extendFlags installedPkgIndex sourcePkgDb initFlags
case license initFlags' of
Flag PublicDomain -> return ()
_ -> writeLicense initFlags'
writeSetupFile initFlags'
writeChangeLog initFlags'
createSourceDirectories initFlags'
createMainHs initFlags'
success <- writeCabalFile initFlags'
when success $ generateWarnings initFlags'
---------------------------------------------------------------------------
-- Flag acquisition -----------------------------------------------------
---------------------------------------------------------------------------
-- | Fill in more details by guessing, discovering, or prompting the
-- user.
extendFlags :: InstalledPackageIndex -> SourcePackageDb -> InitFlags -> IO InitFlags
extendFlags pkgIx sourcePkgDb =
getPackageName sourcePkgDb
>=> getVersion
>=> getLicense
>=> getAuthorInfo
>=> getHomepage
>=> getSynopsis
>=> getCategory
>=> getExtraSourceFiles
>=> getLibOrExec
>=> getSrcDir
>=> getLanguage
>=> getGenComments
>=> getModulesBuildToolsAndDeps pkgIx
-- | Combine two actions which may return a value, preferring the first. That
-- is, run the second action only if the first doesn't return a value.
infixr 1 ?>>
(?>>) :: IO (Maybe a) -> IO (Maybe a) -> IO (Maybe a)
f ?>> g = do
ma <- f
if isJust ma
then return ma
else g
-- | Witness the isomorphism between Maybe and Flag.
maybeToFlag :: Maybe a -> Flag a
maybeToFlag = maybe NoFlag Flag
-- | Get the package name: use the package directory (supplied, or the current
-- directory by default) as a guess. It looks at the SourcePackageDb to avoid
-- using an existing package name.
getPackageName :: SourcePackageDb -> InitFlags -> IO InitFlags
getPackageName sourcePkgDb flags = do
guess <- traverse guessPackageName (flagToMaybe $ packageDir flags)
?>> Just `fmap` (getCurrentDirectory >>= guessPackageName)
let guess' | isPkgRegistered guess = Nothing
| otherwise = guess
pkgName' <- return (flagToMaybe $ packageName flags)
?>> maybePrompt flags (prompt "Package name" guess')
?>> return guess'
chooseAgain <- if isPkgRegistered pkgName'
then promptYesNo promptOtherNameMsg (Just True)
else return False
if chooseAgain
then getPackageName sourcePkgDb flags
else return $ flags { packageName = maybeToFlag pkgName' }
where
isPkgRegistered (Just pkg) = elemByPackageName (packageIndex sourcePkgDb) pkg
isPkgRegistered Nothing = False
promptOtherNameMsg = "This package name is already used by another " ++
"package on hackage. Do you want to choose a " ++
"different name"
-- | Package version: use 0.1.0.0 as a last resort, but try prompting the user
-- if possible.
getVersion :: InitFlags -> IO InitFlags
getVersion flags = do
let v = Just $ Version [0,1,0,0] []
v' <- return (flagToMaybe $ version flags)
?>> maybePrompt flags (prompt "Package version" v)
?>> return v
return $ flags { version = maybeToFlag v' }
-- | Choose a license.
getLicense :: InitFlags -> IO InitFlags
getLicense flags = do
lic <- return (flagToMaybe $ license flags)
?>> fmap (fmap (either UnknownLicense id))
(maybePrompt flags
(promptList "Please choose a license" listedLicenses (Just BSD3) display True))
return $ flags { license = maybeToFlag lic }
where
listedLicenses =
knownLicenses \\ [GPL Nothing, LGPL Nothing, AGPL Nothing
, Apache Nothing, OtherLicense]
-- | The author's name and email. Prompt, or try to guess from an existing
-- darcs repo.
getAuthorInfo :: InitFlags -> IO InitFlags
getAuthorInfo flags = do
(authorName, authorEmail) <-
(flagToMaybe *** flagToMaybe) `fmap` guessAuthorNameMail
authorName' <- return (flagToMaybe $ author flags)
?>> maybePrompt flags (promptStr "Author name" authorName)
?>> return authorName
authorEmail' <- return (flagToMaybe $ email flags)
?>> maybePrompt flags (promptStr "Maintainer email" authorEmail)
?>> return authorEmail
return $ flags { author = maybeToFlag authorName'
, email = maybeToFlag authorEmail'
}
-- | Prompt for a homepage URL.
getHomepage :: InitFlags -> IO InitFlags
getHomepage flags = do
hp <- queryHomepage
hp' <- return (flagToMaybe $ homepage flags)
?>> maybePrompt flags (promptStr "Project homepage URL" hp)
?>> return hp
return $ flags { homepage = maybeToFlag hp' }
-- | Right now this does nothing, but it could be changed to do some
-- intelligent guessing.
queryHomepage :: IO (Maybe String)
queryHomepage = return Nothing -- get default remote darcs repo?
-- | Prompt for a project synopsis.
getSynopsis :: InitFlags -> IO InitFlags
getSynopsis flags = do
syn <- return (flagToMaybe $ synopsis flags)
?>> maybePrompt flags (promptStr "Project synopsis" Nothing)
return $ flags { synopsis = maybeToFlag syn }
-- | Prompt for a package category.
-- Note that it should be possible to do some smarter guessing here too, i.e.
-- look at the name of the top level source directory.
getCategory :: InitFlags -> IO InitFlags
getCategory flags = do
cat <- return (flagToMaybe $ category flags)
?>> fmap join (maybePrompt flags
(promptListOptional "Project category" [Codec ..]))
return $ flags { category = maybeToFlag cat }
-- | Try to guess extra source files (don't prompt the user).
getExtraSourceFiles :: InitFlags -> IO InitFlags
getExtraSourceFiles flags = do
extraSrcFiles <- return (extraSrc flags)
?>> Just `fmap` guessExtraSourceFiles flags
return $ flags { extraSrc = extraSrcFiles }
defaultChangeLog :: FilePath
defaultChangeLog = "ChangeLog.md"
-- | Try to guess things to include in the extra-source-files field.
-- For now, we just look for things in the root directory named
-- 'readme', 'changes', or 'changelog', with any sort of
-- capitalization and any extension.
guessExtraSourceFiles :: InitFlags -> IO [FilePath]
guessExtraSourceFiles flags = do
dir <-
maybe getCurrentDirectory return . flagToMaybe $ packageDir flags
files <- getDirectoryContents dir
let extraFiles = filter isExtra files
if any isLikeChangeLog extraFiles
then return extraFiles
else return (defaultChangeLog : extraFiles)
where
isExtra = likeFileNameBase ("README" : changeLogLikeBases)
isLikeChangeLog = likeFileNameBase changeLogLikeBases
likeFileNameBase candidates = (`elem` candidates) . map toUpper . takeBaseName
changeLogLikeBases = ["CHANGES", "CHANGELOG"]
-- | Ask whether the project builds a library or executable.
getLibOrExec :: InitFlags -> IO InitFlags
getLibOrExec flags = do
isLib <- return (flagToMaybe $ packageType flags)
?>> maybePrompt flags (either (const Library) id `fmap`
promptList "What does the package build"
[Library, Executable]
Nothing display False)
?>> return (Just Library)
mainFile <- if isLib /= Just Executable then return Nothing else
getMainFile flags
return $ flags { packageType = maybeToFlag isLib
, mainIs = maybeToFlag mainFile
}
-- | Try to guess the main file of the executable, and prompt the user to choose
-- one of them. Top-level modules including the word 'Main' in the file name
-- will be candidates, and shorter filenames will be preferred.
getMainFile :: InitFlags -> IO (Maybe FilePath)
getMainFile flags =
return (flagToMaybe $ mainIs flags)
?>> do
candidates <- guessMainFileCandidates flags
let showCandidate = either (++" (does not yet exist, but will be created)") id
defaultFile = listToMaybe candidates
maybePrompt flags (either id (either id id) `fmap`
promptList "What is the main module of the executable"
candidates
defaultFile showCandidate True)
?>> return (fmap (either id id) defaultFile)
-- | Ask for the base language of the package.
getLanguage :: InitFlags -> IO InitFlags
getLanguage flags = do
lang <- return (flagToMaybe $ language flags)
?>> maybePrompt flags
(either UnknownLanguage id `fmap`
promptList "What base language is the package written in"
[Haskell2010, Haskell98]
(Just Haskell2010) display True)
?>> return (Just Haskell2010)
return $ flags { language = maybeToFlag lang }
-- | Ask whether to generate explanatory comments.
getGenComments :: InitFlags -> IO InitFlags
getGenComments flags = do
genComments <- return (not <$> flagToMaybe (noComments flags))
?>> maybePrompt flags (promptYesNo promptMsg (Just False))
?>> return (Just False)
return $ flags { noComments = maybeToFlag (fmap not genComments) }
where
promptMsg = "Add informative comments to each field in the cabal file (y/n)"
-- | Ask for the source root directory.
getSrcDir :: InitFlags -> IO InitFlags
getSrcDir flags = do
srcDirs <- return (sourceDirs flags)
?>> fmap (:[]) `fmap` guessSourceDir flags
?>> fmap (fmap ((:[]) . either id id) . join) (maybePrompt
flags
(promptListOptional' "Source directory" ["src"] id))
return $ flags { sourceDirs = srcDirs }
-- | Try to guess source directory. Could try harder; for the
-- moment just looks to see whether there is a directory called 'src'.
guessSourceDir :: InitFlags -> IO (Maybe String)
guessSourceDir flags = do
dir <-
maybe getCurrentDirectory return . flagToMaybe $ packageDir flags
srcIsDir <- doesDirectoryExist (dir </> "src")
return $ if srcIsDir
then Just "src"
else Nothing
-- | Get the list of exposed modules and extra tools needed to build them.
getModulesBuildToolsAndDeps :: InstalledPackageIndex -> InitFlags -> IO InitFlags
getModulesBuildToolsAndDeps pkgIx flags = do
dir <- maybe getCurrentDirectory return . flagToMaybe $ packageDir flags
-- TODO: really should use guessed source roots.
sourceFiles <- scanForModules dir
Just mods <- return (exposedModules flags)
?>> (return . Just . map moduleName $ sourceFiles)
tools <- return (buildTools flags)
?>> (return . Just . neededBuildPrograms $ sourceFiles)
deps <- return (dependencies flags)
?>> Just <$> importsToDeps flags
(fromString "Prelude" : -- to ensure we get base as a dep
( nub -- only need to consider each imported package once
. filter (`notElem` mods) -- don't consider modules from
-- this package itself
. concatMap imports
$ sourceFiles
)
)
pkgIx
exts <- return (otherExts flags)
?>> (return . Just . nub . concatMap extensions $ sourceFiles)
return $ flags { exposedModules = Just mods
, buildTools = tools
, dependencies = deps
, otherExts = exts
}
importsToDeps :: InitFlags -> [ModuleName] -> InstalledPackageIndex -> IO [P.Dependency]
importsToDeps flags mods pkgIx = do
let modMap :: M.Map ModuleName [InstalledPackageInfo]
modMap = M.map (filter exposed) $ moduleNameIndex pkgIx
modDeps :: [(ModuleName, Maybe [InstalledPackageInfo])]
modDeps = map (id &&& flip M.lookup modMap) mods
message flags "\nGuessing dependencies..."
nub . catMaybes <$> mapM (chooseDep flags) modDeps
-- Given a module and a list of installed packages providing it,
-- choose a dependency (i.e. package + version range) to use for that
-- module.
chooseDep :: InitFlags -> (ModuleName, Maybe [InstalledPackageInfo])
-> IO (Maybe P.Dependency)
chooseDep flags (m, Nothing)
= message flags ("\nWarning: no package found providing " ++ display m ++ ".")
>> return Nothing
chooseDep flags (m, Just [])
= message flags ("\nWarning: no package found providing " ++ display m ++ ".")
>> return Nothing
-- We found some packages: group them by name.
chooseDep flags (m, Just ps)
= case pkgGroups of
-- if there's only one group, i.e. multiple versions of a single package,
-- we make it into a dependency, choosing the latest-ish version (see toDep).
[grp] -> Just <$> toDep grp
-- otherwise, we refuse to choose between different packages and make the user
-- do it.
grps -> do message flags ("\nWarning: multiple packages found providing "
++ display m
++ ": " ++ intercalate ", " (map (display . P.pkgName . head) grps))
message flags "You will need to pick one and manually add it to the Build-depends: field."
return Nothing
where
pkgGroups = groupBy ((==) `on` P.pkgName) (map sourcePackageId ps)
-- Given a list of available versions of the same package, pick a dependency.
toDep :: [P.PackageIdentifier] -> IO P.Dependency
-- If only one version, easy. We change e.g. 0.4.2 into 0.4.*
toDep [pid] = return $ P.Dependency (P.pkgName pid) (pvpize . P.pkgVersion $ pid)
-- Otherwise, choose the latest version and issue a warning.
toDep pids = do
message flags ("\nWarning: multiple versions of " ++ display (P.pkgName . head $ pids) ++ " provide " ++ display m ++ ", choosing the latest.")
return $ P.Dependency (P.pkgName . head $ pids)
(pvpize . maximum . map P.pkgVersion $ pids)
pvpize :: Version -> VersionRange
pvpize v = orLaterVersion v'
`intersectVersionRanges`
earlierVersion (incVersion 1 v')
where v' = (v { versionBranch = take 2 (versionBranch v) })
incVersion :: Int -> Version -> Version
incVersion n (Version vlist tags) = Version (incVersion' n vlist) tags
where
incVersion' 0 [] = [1]
incVersion' 0 (v:_) = [v+1]
incVersion' m [] = replicate m 0 ++ [1]
incVersion' m (v:vs) = v : incVersion' (m-1) vs
---------------------------------------------------------------------------
-- Prompting/user interaction -------------------------------------------
---------------------------------------------------------------------------
-- | Run a prompt or not based on the nonInteractive flag of the
-- InitFlags structure.
maybePrompt :: InitFlags -> IO t -> IO (Maybe t)
maybePrompt flags p =
case nonInteractive flags of
Flag True -> return Nothing
_ -> Just `fmap` p
-- | Create a prompt with optional default value that returns a
-- String.
promptStr :: String -> Maybe String -> IO String
promptStr = promptDefault' Just id
-- | Create a yes/no prompt with optional default value.
--
promptYesNo :: String -> Maybe Bool -> IO Bool
promptYesNo =
promptDefault' recogniseYesNo showYesNo
where
recogniseYesNo s | s == "y" || s == "Y" = Just True
| s == "n" || s == "N" = Just False
| otherwise = Nothing
showYesNo True = "y"
showYesNo False = "n"
-- | Create a prompt with optional default value that returns a value
-- of some Text instance.
prompt :: Text t => String -> Maybe t -> IO t
prompt = promptDefault'
(either (const Nothing) Just . runReadE (readP_to_E id parse))
display
-- | Create a prompt with an optional default value.
promptDefault' :: (String -> Maybe t) -- ^ parser
-> (t -> String) -- ^ pretty-printer
-> String -- ^ prompt message
-> Maybe t -- ^ optional default value
-> IO t
promptDefault' parser pretty pr def = do
putStr $ mkDefPrompt pr (pretty `fmap` def)
inp <- getLine
case (inp, def) of
("", Just d) -> return d
_ -> case parser inp of
Just t -> return t
Nothing -> do putStrLn $ "Couldn't parse " ++ inp ++ ", please try again!"
promptDefault' parser pretty pr def
-- | Create a prompt from a prompt string and a String representation
-- of an optional default value.
mkDefPrompt :: String -> Maybe String -> String
mkDefPrompt pr def = pr ++ "?" ++ defStr def
where defStr Nothing = " "
defStr (Just s) = " [default: " ++ s ++ "] "
promptListOptional :: (Text t, Eq t)
=> String -- ^ prompt
-> [t] -- ^ choices
-> IO (Maybe (Either String t))
promptListOptional pr choices = promptListOptional' pr choices display
promptListOptional' :: Eq t
=> String -- ^ prompt
-> [t] -- ^ choices
-> (t -> String) -- ^ show an item
-> IO (Maybe (Either String t))
promptListOptional' pr choices displayItem =
fmap rearrange
$ promptList pr (Nothing : map Just choices) (Just Nothing)
(maybe "(none)" displayItem) True
where
rearrange = either (Just . Left) (fmap Right)
-- | Create a prompt from a list of items.
promptList :: Eq t
=> String -- ^ prompt
-> [t] -- ^ choices
-> Maybe t -- ^ optional default value
-> (t -> String) -- ^ show an item
-> Bool -- ^ whether to allow an 'other' option
-> IO (Either String t)
promptList pr choices def displayItem other = do
putStrLn $ pr ++ ":"
let options1 = map (\c -> (Just c == def, displayItem c)) choices
options2 = zip ([1..]::[Int])
(options1 ++ [(False, "Other (specify)") | other])
mapM_ (putStrLn . \(n,(i,s)) -> showOption n i ++ s) options2
promptList' displayItem (length options2) choices def other
where showOption n i | n < 10 = " " ++ star i ++ " " ++ rest
| otherwise = " " ++ star i ++ rest
where rest = show n ++ ") "
star True = "*"
star False = " "
promptList' :: (t -> String) -> Int -> [t] -> Maybe t -> Bool -> IO (Either String t)
promptList' displayItem numChoices choices def other = do
putStr $ mkDefPrompt "Your choice" (displayItem `fmap` def)
inp <- getLine
case (inp, def) of
("", Just d) -> return $ Right d
_ -> case readMaybe inp of
Nothing -> invalidChoice inp
Just n -> getChoice n
where invalidChoice inp = do putStrLn $ inp ++ " is not a valid choice."
promptList' displayItem numChoices choices def other
getChoice n | n < 1 || n > numChoices = invalidChoice (show n)
| n < numChoices ||
(n == numChoices && not other)
= return . Right $ choices !! (n-1)
| otherwise = Left `fmap` promptStr "Please specify" Nothing
readMaybe :: (Read a) => String -> Maybe a
readMaybe s = case reads s of
[(a,"")] -> Just a
_ -> Nothing
---------------------------------------------------------------------------
-- File generation ------------------------------------------------------
---------------------------------------------------------------------------
writeLicense :: InitFlags -> IO ()
writeLicense flags = do
message flags "\nGenerating LICENSE..."
year <- show <$> getYear
let authors = fromMaybe "???" . flagToMaybe . author $ flags
let licenseFile =
case license flags of
Flag BSD2
-> Just $ bsd2 authors year
Flag BSD3
-> Just $ bsd3 authors year
Flag (GPL (Just (Version {versionBranch = [2]})))
-> Just gplv2
Flag (GPL (Just (Version {versionBranch = [3]})))
-> Just gplv3
Flag (LGPL (Just (Version {versionBranch = [2, 1]})))
-> Just lgpl21
Flag (LGPL (Just (Version {versionBranch = [3]})))
-> Just lgpl3
Flag (AGPL (Just (Version {versionBranch = [3]})))
-> Just agplv3
Flag (Apache (Just (Version {versionBranch = [2, 0]})))
-> Just apache20
Flag MIT
-> Just $ mit authors year
Flag (MPL (Version {versionBranch = [2, 0]}))
-> Just mpl20
Flag ISC
-> Just $ isc authors year
_ -> Nothing
case licenseFile of
Just licenseText -> writeFileSafe flags "LICENSE" licenseText
Nothing -> message flags "Warning: unknown license type, you must put a copy in LICENSE yourself."
getYear :: IO Integer
getYear = do
u <- getCurrentTime
z <- getCurrentTimeZone
let l = utcToLocalTime z u
(y, _, _) = toGregorian $ localDay l
return y
writeSetupFile :: InitFlags -> IO ()
writeSetupFile flags = do
message flags "Generating Setup.hs..."
writeFileSafe flags "Setup.hs" setupFile
where
setupFile = unlines
[ "import Distribution.Simple"
, "main = defaultMain"
]
writeChangeLog :: InitFlags -> IO ()
writeChangeLog flags = when (any (== defaultChangeLog) $ maybe [] id (extraSrc flags)) $ do
message flags ("Generating "++ defaultChangeLog ++"...")
writeFileSafe flags defaultChangeLog changeLog
where
changeLog = unlines
[ "# Revision history for " ++ pname
, ""
, "## " ++ pver ++ " -- YYYY-mm-dd"
, ""
, "* First version. Released on an unsuspecting world."
]
pname = maybe "" display $ flagToMaybe $ packageName flags
pver = maybe "" display $ flagToMaybe $ version flags
writeCabalFile :: InitFlags -> IO Bool
writeCabalFile flags@(InitFlags{packageName = NoFlag}) = do
message flags "Error: no package name provided."
return False
writeCabalFile flags@(InitFlags{packageName = Flag p}) = do
let cabalFileName = display p ++ ".cabal"
message flags $ "Generating " ++ cabalFileName ++ "..."
writeFileSafe flags cabalFileName (generateCabalFile cabalFileName flags)
return True
-- | Write a file \"safely\", backing up any existing version (unless
-- the overwrite flag is set).
writeFileSafe :: InitFlags -> FilePath -> String -> IO ()
writeFileSafe flags fileName content = do
moveExistingFile flags fileName
writeFile fileName content
-- | Create source directories, if they were given.
createSourceDirectories :: InitFlags -> IO ()
createSourceDirectories flags = case sourceDirs flags of
Just dirs -> forM_ dirs (createDirectoryIfMissing True)
Nothing -> return ()
-- | Create Main.hs, but only if we are init'ing an executable and
-- the mainIs flag has been provided.
createMainHs :: InitFlags -> IO ()
createMainHs flags@InitFlags{ sourceDirs = Just (srcPath:_)
, packageType = Flag Executable
, mainIs = Flag mainFile } =
writeMainHs flags (srcPath </> mainFile)
createMainHs flags@InitFlags{ sourceDirs = _
, packageType = Flag Executable
, mainIs = Flag mainFile } =
writeMainHs flags mainFile
createMainHs _ = return ()
-- | Write a main file if it doesn't already exist.
writeMainHs :: InitFlags -> FilePath -> IO ()
writeMainHs flags mainPath = do
dir <- maybe getCurrentDirectory return (flagToMaybe $ packageDir flags)
let mainFullPath = dir </> mainPath
exists <- doesFileExist mainFullPath
unless exists $ do
message flags $ "Generating " ++ mainPath ++ "..."
writeFileSafe flags mainFullPath mainHs
-- | Default Main.hs file. Used when no Main.hs exists.
mainHs :: String
mainHs = unlines
[ "module Main where"
, ""
, "main :: IO ()"
, "main = putStrLn \"Hello, Haskell!\""
]
-- | Move an existing file, if there is one, and the overwrite flag is
-- not set.
moveExistingFile :: InitFlags -> FilePath -> IO ()
moveExistingFile flags fileName =
unless (overwrite flags == Flag True) $ do
e <- doesFileExist fileName
when e $ do
newName <- findNewName fileName
message flags $ "Warning: " ++ fileName ++ " already exists, backing up old version in " ++ newName
copyFile fileName newName
findNewName :: FilePath -> IO FilePath
findNewName oldName = findNewName' 0
where
findNewName' :: Integer -> IO FilePath
findNewName' n = do
let newName = oldName <.> ("save" ++ show n)
e <- doesFileExist newName
if e then findNewName' (n+1) else return newName
-- | Generate a .cabal file from an InitFlags structure. NOTE: this
-- is rather ad-hoc! What we would REALLY like is to have a
-- standard low-level AST type representing .cabal files, which
-- preserves things like comments, and to write an *inverse*
-- parser/pretty-printer pair between .cabal files and this AST.
-- Then instead of this ad-hoc code we could just map an InitFlags
-- structure onto a low-level AST structure and use the existing
-- pretty-printing code to generate the file.
generateCabalFile :: String -> InitFlags -> String
generateCabalFile fileName c =
(++ "\n") .
renderStyle style { lineLength = 79, ribbonsPerLine = 1.1 } $
(if minimal c /= Flag True
then showComment (Just $ "Initial " ++ fileName ++ " generated by cabal "
++ "init. For further documentation, see "
++ "http://haskell.org/cabal/users-guide/")
$$ text ""
else empty)
$$
vcat [ field "name" (packageName c)
(Just "The name of the package.")
True
, field "version" (version c)
(Just $ "The package version. See the Haskell package versioning policy (PVP) for standards guiding when and how versions should be incremented.\nhttps://wiki.haskell.org/Package_versioning_policy\n"
++ "PVP summary: +-+------- breaking API changes\n"
++ " | | +----- non-breaking API additions\n"
++ " | | | +--- code changes with no API change")
True
, fieldS "synopsis" (synopsis c)
(Just "A short (one-line) description of the package.")
True
, fieldS "description" NoFlag
(Just "A longer description of the package.")
True
, fieldS "homepage" (homepage c)
(Just "URL for the project homepage or repository.")
False
, fieldS "bug-reports" NoFlag
(Just "A URL where users can report bugs.")
False
, field "license" (license c)
(Just "The license under which the package is released.")
True
, case (license c) of
Flag PublicDomain -> empty
_ -> fieldS "license-file" (Flag "LICENSE")
(Just "The file containing the license text.")
True
, fieldS "author" (author c)
(Just "The package author(s).")
True
, fieldS "maintainer" (email c)
(Just "An email address to which users can send suggestions, bug reports, and patches.")
True
, case (license c) of
Flag PublicDomain -> empty
_ -> fieldS "copyright" NoFlag
(Just "A copyright notice.")
True
, fieldS "category" (either id display `fmap` category c)
Nothing
True
, fieldS "build-type" (Flag "Simple")
Nothing
True
, fieldS "extra-source-files" (listFieldS (extraSrc c))
(Just "Extra files to be distributed with the package, such as examples or a README.")
True
, field "cabal-version" (Flag $ orLaterVersion (Version [1,10] []))
(Just "Constraint on the version of Cabal needed to build this package.")
False
, case packageType c of
Flag Executable ->
text "\nexecutable" <+>
text (maybe "" display . flagToMaybe $ packageName c) $$
nest 2 (vcat
[ fieldS "main-is" (mainIs c) (Just ".hs or .lhs file containing the Main module.") True
, generateBuildInfo Executable c
])
Flag Library -> text "\nlibrary" $$ nest 2 (vcat
[ fieldS "exposed-modules" (listField (exposedModules c))
(Just "Modules exported by the library.")
True
, generateBuildInfo Library c
])
_ -> empty
]
where
generateBuildInfo :: PackageType -> InitFlags -> Doc
generateBuildInfo pkgtype c' = vcat
[ fieldS "other-modules" (listField (otherModules c'))
(Just $ case pkgtype of
Library -> "Modules included in this library but not exported."
Executable -> "Modules included in this executable, other than Main.")
True
, fieldS "other-extensions" (listField (otherExts c'))
(Just "LANGUAGE extensions used by modules in this package.")
True
, fieldS "build-depends" (listField (dependencies c'))
(Just "Other library packages from which modules are imported.")
True
, fieldS "hs-source-dirs" (listFieldS (sourceDirs c'))
(Just "Directories containing source files.")
True
, fieldS "build-tools" (listFieldS (buildTools c'))
(Just "Extra tools (e.g. alex, hsc2hs, ...) needed to build the source.")
False
, field "default-language" (language c')
(Just "Base language which the package is written in.")
True
]
listField :: Text s => Maybe [s] -> Flag String
listField = listFieldS . fmap (map display)
listFieldS :: Maybe [String] -> Flag String
listFieldS = Flag . maybe "" (intercalate ", ")
field :: Text t => String -> Flag t -> Maybe String -> Bool -> Doc
field s f = fieldS s (fmap display f)
fieldS :: String -- ^ Name of the field
-> Flag String -- ^ Field contents
-> Maybe String -- ^ Comment to explain the field
-> Bool -- ^ Should the field be included (commented out) even if blank?
-> Doc
fieldS _ NoFlag _ inc | not inc || (minimal c == Flag True) = empty
fieldS _ (Flag "") _ inc | not inc || (minimal c == Flag True) = empty
fieldS s f com _ = case (isJust com, noComments c, minimal c) of
(_, _, Flag True) -> id
(_, Flag True, _) -> id
(True, _, _) -> (showComment com $$) . ($$ text "")
(False, _, _) -> ($$ text "")
$
comment f <> text s <> colon
<> text (replicate (20 - length s) ' ')
<> text (fromMaybe "" . flagToMaybe $ f)
comment NoFlag = text "-- "
comment (Flag "") = text "-- "
comment _ = text ""
showComment :: Maybe String -> Doc
showComment (Just t) = vcat
. map (text . ("-- "++)) . lines
. renderStyle style {
lineLength = 76,
ribbonsPerLine = 1.05
}
. vcat
. map (fcat . map text . breakLine)
. lines
$ t
showComment Nothing = text ""
breakLine [] = []
breakLine cs = case break (==' ') cs of (w,cs') -> w : breakLine' cs'
breakLine' [] = []
breakLine' cs = case span (==' ') cs of (w,cs') -> w : breakLine cs'
-- | Generate warnings for missing fields etc.
generateWarnings :: InitFlags -> IO ()
generateWarnings flags = do
message flags ""
when (synopsis flags `elem` [NoFlag, Flag ""])
(message flags "Warning: no synopsis given. You should edit the .cabal file and add one.")
message flags "You may want to edit the .cabal file and add a Description field."
-- | Possibly generate a message to stdout, taking into account the
-- --quiet flag.
message :: InitFlags -> String -> IO ()
message (InitFlags{quiet = Flag True}) _ = return ()
message _ s = putStrLn s