Initial feature add: create both Library and Executable on cabal init

cabal-install/Distribution/Client/Init.hs

@@ -60,7 +60,7 @@ import qualified Distribution.Package as P
 import Language.Haskell.Extension ( Language(..) )
 
 import Distribution.Client.Init.Types
-  ( InitFlags(..), PackageType(..), Category(..) )
+  ( InitFlags(..), BuildType(..), PackageType(..), Category(..) )
 import Distribution.Client.Init.Licenses
   ( bsd2, bsd3, gplv2, gplv3, lgpl21, lgpl3, agplv3, apache20, mit, mpl20, isc )
 import Distribution.Client.Init.Heuristics
@@ -310,16 +310,16 @@ guessExtraSourceFiles flags = do
 -- | Ask whether the project builds a library or executable.
 getLibOrExec :: InitFlags -> IO InitFlags
 getLibOrExec flags = do
-  isLib <-     return (flagToMaybe $ packageType flags)
+  pkgType <-     return (flagToMaybe $ packageType flags)
            ?>> maybePrompt flags (either (const Library) id `fmap`
                                    promptList "What does the package build"
-                                   [Library, Executable]
+                                   [Library, Executable, LibraryAndExecutable]
                                    Nothing display False)
            ?>> return (Just Library)
-  mainFile <- if isLib /= Just Executable then return Nothing else
+  mainFile <- if pkgType == Just Library then return Nothing else
                     getMainFile flags
 
-  return $ flags { packageType = maybeToFlag isLib
+  return $ flags { packageType = maybeToFlag pkgType
                  , mainIs = maybeToFlag mainFile
                  }
 
@@ -742,6 +742,14 @@ createMainHs flags@InitFlags{ sourceDirs = _
                             , packageType = Flag Executable
                             , mainIs = Flag mainFile } =
   writeMainHs flags mainFile
+createMainHs flags@InitFlags{ sourceDirs = Just (srcPath:_)
+                            , packageType = Flag LibraryAndExecutable
+                            , mainIs = Flag mainFile } =
+  writeMainHs flags (srcPath </> mainFile)
+createMainHs flags@InitFlags{ sourceDirs = _
+                            , packageType = Flag LibraryAndExecutable
+                            , mainIs = Flag mainFile } =
+  writeMainHs flags mainFile
 createMainHs _ = return ()
 
 -- | Write a main file if it doesn't already exist.
@@ -870,30 +878,18 @@ generateCabalFile fileName c =
                 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
-             ])
+           Flag Executable -> executableStanza
+           Flag Library    -> libraryStanza
+           Flag LibraryAndExecutable -> libraryStanza $+$ executableStanza
            _               -> empty
        ]
  where
-   generateBuildInfo :: PackageType -> InitFlags -> Doc
-   generateBuildInfo pkgtype c' = vcat
+   generateBuildInfo :: BuildType -> InitFlags -> Doc
+   generateBuildInfo artType 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.")
+              (Just $ case artType of
+                 LibBuild    -> "Modules included in this library but not exported."
+                 ExecBuild -> "Modules included in this executable, other than Main.")
               True
 
      , fieldS "other-extensions" (listField (otherExts c'))
@@ -964,6 +960,25 @@ generateCabalFile fileName c =
    breakLine' [] = []
    breakLine' cs = case span (==' ') cs of (w,cs') -> w : breakLine cs'
 
+   executableStanza :: Doc
+   executableStanza = text "\nexecutable" <+>
+             text (maybe "" display . flagToMaybe $ packageName c) $$
+             nest 2 (vcat
+             [ fieldS "main-is" (mainIs c) (Just ".hs or .lhs file containing the Main module.") True
+
+             , generateBuildInfo ExecBuild c
+             ])
+
+   libraryStanza :: Doc
+   libraryStanza = text "\nlibrary" $$ nest 2 (vcat
+             [ fieldS "exposed-modules" (listField (exposedModules c))
+                      (Just "Modules exported by the library.")
+                      True
+
+             , generateBuildInfo LibBuild c
+             ])
+
+
 -- | Generate warnings for missing fields etc.
 generateWarnings :: InitFlags -> IO ()
 generateWarnings flags = do

cabal-install/Distribution/Client/Init/Types.hs

@@ -78,12 +78,14 @@ data InitFlags =
   -- ones, which is why we want Maybe [foo] for collecting foo values,
   -- not Flag [foo].
 
-data PackageType = Library | Executable
+data BuildType = LibBuild | ExecBuild
+
+data PackageType = Library | Executable | LibraryAndExecutable
   deriving (Show, Read, Eq)
 
 instance Text PackageType where
   disp = Disp.text . show
-  parse = Parse.choice $ map (fmap read . Parse.string . show) [Library, Executable] -- TODO: eradicateNoParse
+  parse = Parse.choice $ map (fmap read . Parse.string . show) [Library, Executable, LibraryAndExecutable] -- TODO: eradicateNoParse
 
 instance Monoid InitFlags where
   mempty = gmempty

cabal-install/Distribution/Client/Setup.hs

@@ -2012,6 +2012,12 @@ initCommand = CommandUI {
         (\v flags -> flags { IT.packageType = v })
         (noArg (Flag IT.Executable))
 
+        , option [] ["is-libandexec"]
+        "Build a library and an executable."
+        IT.packageType
+        (\v flags -> flags { IT.packageType = v })
+        (noArg (Flag IT.LibraryAndExecutable))
+
       , option [] ["main-is"]
         "Specify the main module."
         IT.mainIs