Convenience libraries

.gitignore

@@ -28,6 +28,7 @@ dist-*
 .#*
 *~
 .*.swp
+*.bak
 
 # GHC build
 

.travis.yml

@@ -81,7 +81,7 @@ script:
  - ./dist/setup/setup test unit-tests --show-details=streaming --test-option=--hide-successes
  - ./dist/setup/setup test integration-tests --show-details=streaming --test-option=--hide-successes
  - cabal check
- - cabal sdist
+ - ./dist/setup/setup sdist
  - install_from_tarball
 
 # Check what we got

Cabal/Cabal.cabal

@@ -86,6 +86,15 @@ extra-source-files:
   tests/PackageTests/CMain/Bar.hs
   tests/PackageTests/CMain/foo.c
   tests/PackageTests/CMain/my.cabal
+  tests/PackageTests/Configure/A.hs
+  tests/PackageTests/Configure/Setup.hs
+  tests/PackageTests/Configure/X11.cabal
+  tests/PackageTests/CopyComponent/Exe/Main.hs
+  tests/PackageTests/CopyComponent/Exe/Main2.hs
+  tests/PackageTests/CopyComponent/Exe/myprog.cabal
+  tests/PackageTests/CopyComponent/Lib/Main.hs
+  tests/PackageTests/CopyComponent/Lib/p.cabal
+  tests/PackageTests/CopyComponent/Lib/src/P.hs
   tests/PackageTests/DeterministicAr/Lib.hs
   tests/PackageTests/DeterministicAr/my.cabal
   tests/PackageTests/DuplicateModuleName/DuplicateModuleName.cabal
@@ -119,6 +128,25 @@ extra-source-files:
   tests/PackageTests/HaddockNewline/A.hs
   tests/PackageTests/HaddockNewline/HaddockNewline.cabal
   tests/PackageTests/HaddockNewline/Setup.hs
+  tests/PackageTests/InternalLibraries/Executable/exe/Main.hs
+  tests/PackageTests/InternalLibraries/Executable/foo.cabal
+  tests/PackageTests/InternalLibraries/Executable/src/Foo.hs
+  tests/PackageTests/InternalLibraries/Library/fooexe/Main.hs
+  tests/PackageTests/InternalLibraries/Library/fooexe/fooexe.cabal
+  tests/PackageTests/InternalLibraries/Library/foolib/Foo.hs
+  tests/PackageTests/InternalLibraries/Library/foolib/foolib.cabal
+  tests/PackageTests/InternalLibraries/Library/foolib/private/Internal.hs
+  tests/PackageTests/InternalLibraries/p/Foo.hs
+  tests/PackageTests/InternalLibraries/p/p.cabal
+  tests/PackageTests/InternalLibraries/p/p/P.hs
+  tests/PackageTests/InternalLibraries/p/q/Q.hs
+  tests/PackageTests/InternalLibraries/q/Q.hs
+  tests/PackageTests/InternalLibraries/q/q.cabal
+  tests/PackageTests/Macros/A.hs
+  tests/PackageTests/Macros/B.hs
+  tests/PackageTests/Macros/Main.hs
+  tests/PackageTests/Macros/macros.cabal
+  tests/PackageTests/Macros/src/C.hs
   tests/PackageTests/Options.hs
   tests/PackageTests/OrderFlags/Foo.hs
   tests/PackageTests/OrderFlags/my.cabal

Cabal/Distribution/ModuleName.hs

@@ -27,6 +27,7 @@ import qualified Distribution.Compat.ReadP as Parse
 
 import qualified Data.Char as Char
          ( isAlphaNum, isUpper )
+import Control.DeepSeq
 import Data.Data (Data)
 import Data.Typeable (Typeable)
 import qualified Text.PrettyPrint as Disp
@@ -43,6 +44,9 @@ newtype ModuleName = ModuleName [String]
 
 instance Binary ModuleName
 
+instance NFData ModuleName where
+    rnf (ModuleName ms) = rnf ms
+
 instance Text ModuleName where
   disp (ModuleName ms) =
     Disp.hcat (intersperse (Disp.char '.') (map Disp.text ms))

Cabal/Distribution/PackageDescription.hs

@@ -43,6 +43,7 @@ module Distribution.PackageDescription (
         ModuleReexport(..),
         emptyLibrary,
         withLib,
+        hasPublicLib,
         hasLibs,
         libModules,
 
@@ -89,6 +90,8 @@ module Distribution.PackageDescription (
         hcSharedOptions,
 
         -- ** Supplementary build information
+        ComponentName(..),
+        defaultLibName,
         HookedBuildInfo,
         emptyHookedBuildInfo,
         updatePackageDescription,
@@ -124,7 +127,6 @@ import Distribution.Text
 import Language.Haskell.Extension
 
 import Data.Data                  (Data)
-import Data.Foldable              (traverse_)
 import Data.List                  (nub, intercalate)
 import Data.Maybe                 (fromMaybe, maybeToList)
 import Data.Foldable as Fold      (Foldable(foldMap))
@@ -189,7 +191,7 @@ data PackageDescription
         buildType      :: Maybe BuildType,
         setupBuildInfo :: Maybe SetupBuildInfo,
         -- components
-        library        :: Maybe Library,
+        libraries      :: [Library],
         executables    :: [Executable],
         testSuites     :: [TestSuite],
         benchmarks     :: [Benchmark],
@@ -256,7 +258,7 @@ emptyPackageDescription
                       category     = "",
                       customFieldsPD = [],
                       setupBuildInfo = Nothing,
-                      library      = Nothing,
+                      libraries    = [],
                       executables  = [],
                       testSuites   = [],
                       benchmarks   = [],
@@ -387,6 +389,7 @@ instance Text ModuleRenaming where
 -- The Library type
 
 data Library = Library {
+        libName :: String,
         exposedModules    :: [ModuleName],
         reexportedModules :: [ModuleReexport],
         requiredSignatures:: [ModuleName], -- ^ What sigs need implementations?
@@ -400,6 +403,7 @@ instance Binary Library
 
 instance Monoid Library where
   mempty = Library {
+    libName = mempty,
     exposedModules = mempty,
     reexportedModules = mempty,
     requiredSignatures = mempty,
@@ -411,6 +415,7 @@ instance Monoid Library where
 
 instance Semigroup Library where
   a <> b = Library {
+    libName = combine' libName,
     exposedModules = combine exposedModules,
     reexportedModules = combine reexportedModules,
     requiredSignatures = combine requiredSignatures,
@@ -419,26 +424,31 @@ instance Semigroup Library where
     libBuildInfo   = combine libBuildInfo
   }
     where combine field = field a `mappend` field b
+          combine' field = case (field a, field b) of
+                      ("","") -> ""
+                      ("", x) -> x
+                      (x, "") -> x
+                      (x, y) -> error $ "Ambiguous values for library field: '"
+                                  ++ x ++ "' and '" ++ y ++ "'"
 
 emptyLibrary :: Library
 emptyLibrary = mempty
 
--- |does this package have any libraries?
-hasLibs :: PackageDescription -> Bool
-hasLibs p = maybe False (buildable . libBuildInfo) (library p)
+-- | Does this package have a PUBLIC library?
+hasPublicLib :: PackageDescription -> Bool
+hasPublicLib p = any f (libraries p)
+    where f lib = buildable (libBuildInfo lib) &&
+                  libName lib == display (packageName (package p))
 
--- |'Maybe' version of 'hasLibs'
-maybeHasLibs :: PackageDescription -> Maybe Library
-maybeHasLibs p =
-   library p >>= \lib -> if buildable (libBuildInfo lib)
-                           then Just lib
-                           else Nothing
+-- | Does this package have any libraries?
+hasLibs :: PackageDescription -> Bool
+hasLibs p = any (buildable . libBuildInfo) (libraries p)
 
 -- |If the package description has a library section, call the given
 --  function with the library build info as argument.
 withLib :: PackageDescription -> (Library -> IO ()) -> IO ()
 withLib pkg_descr f =
-   traverse_ f (maybeHasLibs pkg_descr)
+   sequence_ [f lib | lib <- libraries pkg_descr, buildable (libBuildInfo lib)]
 
 -- | Get all the module names from the library (exposed and internal modules)
 -- which need to be compiled.  (This does not include reexports, which
@@ -915,7 +925,7 @@ emptyBuildInfo = mempty
 -- all buildable executables, test suites and benchmarks.  Useful for gathering
 -- dependencies.
 allBuildInfo :: PackageDescription -> [BuildInfo]
-allBuildInfo pkg_descr = [ bi | Just lib <- [library pkg_descr]
+allBuildInfo pkg_descr = [ bi | lib <- libraries pkg_descr
                               , let bi = libBuildInfo lib
                               , buildable bi ]
                       ++ [ bi | exe <- executables pkg_descr
@@ -950,10 +960,22 @@ usedExtensions :: BuildInfo -> [Extension]
 usedExtensions bi = oldExtensions bi
                  ++ defaultExtensions bi
 
-type HookedBuildInfo = (Maybe BuildInfo, [(String, BuildInfo)])
+-- Libraries live in a separate namespace, so must distinguish
+data ComponentName = CLibName   String
+                   | CExeName   String
+                   | CTestName  String
+                   | CBenchName String
+                   deriving (Eq, Generic, Ord, Read, Show)
+
+instance Binary ComponentName
+
+defaultLibName :: PackageIdentifier -> ComponentName
+defaultLibName pid = CLibName (display (pkgName pid))
+
+type HookedBuildInfo = [(ComponentName, BuildInfo)]
 
 emptyHookedBuildInfo :: HookedBuildInfo
-emptyHookedBuildInfo = (Nothing, [])
+emptyHookedBuildInfo = []
 
 -- |Select options for a particular Haskell compiler.
 hcOptions :: CompilerFlavor -> BuildInfo -> [String]
@@ -1109,28 +1131,38 @@ lowercase = map Char.toLower
 -- ------------------------------------------------------------
 
 updatePackageDescription :: HookedBuildInfo -> PackageDescription -> PackageDescription
-updatePackageDescription (mb_lib_bi, exe_bi) p
-    = p{ executables = updateExecutables exe_bi    (executables p)
-       , library     = updateLibrary     mb_lib_bi (library     p)
-       }
+updatePackageDescription hooked_bis p
+  = p{ executables = updateMany (CExeName . exeName)         updateExecutable (executables p)
+     , libraries   = updateMany (CLibName . libName)         updateLibrary    (libraries   p)
+     , benchmarks  = updateMany (CBenchName . benchmarkName) updateBenchmark  (benchmarks p)
+     , testSuites  = updateMany (CTestName . testName)       updateTestSuite  (testSuites p)
+     }
     where
-      updateLibrary :: Maybe BuildInfo -> Maybe Library -> Maybe Library
-      updateLibrary (Just bi) (Just lib) = Just (lib{libBuildInfo = bi `mappend` libBuildInfo lib})
-      updateLibrary Nothing   mb_lib     = mb_lib
-      updateLibrary (Just _)  Nothing    = Nothing
-
-      updateExecutables :: [(String, BuildInfo)] -- ^[(exeName, new buildinfo)]
-                        -> [Executable]          -- ^list of executables to update
-                        -> [Executable]          -- ^list with exeNames updated
-      updateExecutables exe_bi' executables' = foldr updateExecutable executables' exe_bi'
-
-      updateExecutable :: (String, BuildInfo) -- ^(exeName, new buildinfo)
-                       -> [Executable]        -- ^list of executables to update
-                       -> [Executable]        -- ^list with exeName updated
-      updateExecutable _                 []         = []
-      updateExecutable exe_bi'@(name,bi) (exe:exes)
-        | exeName exe == name = exe{buildInfo = bi `mappend` buildInfo exe} : exes
-        | otherwise           = exe : updateExecutable exe_bi' exes
+      updateMany :: (a -> ComponentName) -- ^ get 'ComponentName' from @a@
+                 -> (BuildInfo -> a -> a) -- ^ @updateExecutable@, @updateLibrary@, etc
+                 -> [a]          -- ^list of components to update
+                 -> [a]          -- ^list with updated components
+      updateMany name update cs' = foldr (updateOne name update) cs' hooked_bis
+
+      updateOne :: (a -> ComponentName) -- ^ get 'ComponentName' from @a@
+                -> (BuildInfo -> a -> a) -- ^ @updateExecutable@, @updateLibrary@, etc
+                -> (ComponentName, BuildInfo) -- ^(name, new buildinfo)
+                -> [a]        -- ^list of components to update
+                -> [a]        -- ^list with name component updated
+      updateOne _ _ _                 []         = []
+      updateOne name_sel update hooked_bi'@(name,bi) (c:cs)
+        | name_sel c == name ||
+          -- Special case: an empty name means "please update the BuildInfo for
+          -- the public library, i.e. the one with the same name as the
+          -- package."  See 'parseHookedBuildInfo'.
+          name == CLibName "" && name_sel c == defaultLibName (package p)
+          = update bi c : cs
+        | otherwise          = c : updateOne name_sel update hooked_bi' cs
+
+      updateExecutable bi exe = exe{buildInfo    = bi `mappend` buildInfo exe}
+      updateLibrary    bi lib = lib{libBuildInfo = bi `mappend` libBuildInfo lib}
+      updateBenchmark  bi ben = ben{benchmarkBuildInfo = bi `mappend` benchmarkBuildInfo ben}
+      updateTestSuite  bi test = test{testBuildInfo = bi `mappend` testBuildInfo test}
 
 -- ---------------------------------------------------------------------------
 -- The GenericPackageDescription type
@@ -1139,7 +1171,7 @@ data GenericPackageDescription =
     GenericPackageDescription {
         packageDescription :: PackageDescription,
         genPackageFlags       :: [Flag],
-        condLibrary        :: Maybe (CondTree ConfVar [Dependency] Library),
+        condLibraries      :: [(String, CondTree ConfVar [Dependency] Library)],
         condExecutables    :: [(String, CondTree ConfVar [Dependency] Executable)],
         condTestSuites     :: [(String, CondTree ConfVar [Dependency] TestSuite)],
         condBenchmarks     :: [(String, CondTree ConfVar [Dependency] Benchmark)]

Cabal/Distribution/PackageDescription/Check.hs

@@ -46,7 +46,7 @@ import Distribution.Text
 import Language.Haskell.Extension
 
 import Data.Maybe
-         ( isNothing, isJust, catMaybes, mapMaybe, maybeToList, fromMaybe )
+         ( isNothing, isJust, catMaybes, mapMaybe, fromMaybe )
 import Data.List  (sort, group, isPrefixOf, nub, find)
 import Control.Monad
          ( filterM, liftM )
@@ -173,19 +173,19 @@ checkSanity pkg =
   , check (all ($ pkg) [ null . executables
                        , null . testSuites
                        , null . benchmarks
-                       , isNothing . library ]) $
+                       , null . libraries ]) $
       PackageBuildImpossible
         "No executables, libraries, tests, or benchmarks found. Nothing to do."
 
   , check (not (null duplicateNames)) $
       PackageBuildImpossible $ "Duplicate sections: " ++ commaSep duplicateNames
-        ++ ". The name of every executable, test suite, and benchmark section in"
+        ++ ". The name of every library, executable, test suite, and benchmark section in"
         ++ " the package must be unique."
   ]
   --TODO: check for name clashes case insensitively: windows file systems cannot
   --cope.
 
-  ++ maybe []  (checkLibrary    pkg) (library pkg)
+  ++ concatMap (checkLibrary    pkg) (libraries pkg)
   ++ concatMap (checkExecutable pkg) (executables pkg)
   ++ concatMap (checkTestSuite  pkg) (testSuites pkg)
   ++ concatMap (checkBenchmark  pkg) (benchmarks pkg)
@@ -199,10 +199,15 @@ checkSanity pkg =
         ++ "tool only supports up to version " ++ display cabalVersion ++ "."
   ]
   where
+    -- The public library gets special dispensation, because it
+    -- is common practice to export a library and name the executable
+    -- the same as the package.  We always put the public library
+    -- in the top-level directory in dist, so no conflicts either.
+    libNames = filter (/= unPackageName (packageName pkg)) . map libName $ libraries pkg
     exeNames = map exeName $ executables pkg
     testNames = map testName $ testSuites pkg
     bmNames = map benchmarkName $ benchmarks pkg
-    duplicateNames = dups $ exeNames ++ testNames ++ bmNames
+    duplicateNames = dups $ libNames ++ exeNames ++ testNames ++ bmNames
 
 checkLibrary :: PackageDescription -> Library -> [PackageCheck]
 checkLibrary pkg lib =
@@ -359,6 +364,11 @@ checkFields pkg =
         ++ "need to convert package names to file names so using this name "
         ++ "would cause problems."
 
+  , check ((isPrefixOf "z-") . display . packageName $ pkg) $
+      PackageDistInexcusable $
+           "Package names with the prefix 'z-' are reserved by Cabal and "
+        ++ "cannot be used."
+
   , check (isNothing (buildType pkg)) $
       PackageBuildWarning $
            "No 'build-type' specified. If you do not need a custom Setup.hs or "
@@ -681,7 +691,7 @@ checkGhcOptions pkg =
 
   where
     all_ghc_options    = concatMap get_ghc_options (allBuildInfo pkg)
-    lib_ghc_options    = maybe [] (get_ghc_options . libBuildInfo) (library pkg)
+    lib_ghc_options    = concatMap (get_ghc_options . libBuildInfo) (libraries pkg)
     get_ghc_options bi = hcOptions GHC bi ++ hcProfOptions GHC bi
                          ++ hcSharedOptions GHC bi
 
@@ -904,9 +914,18 @@ checkCabalVersion pkg =
         ++ "different modules then list the other ones in the "
         ++ "'other-languages' field."
 
+  , checkVersion [1,23]
+    (case libraries pkg of
+        [lib] -> libName lib /= unPackageName (packageName pkg)
+        [] -> False
+        _ -> True) $
+      PackageDistInexcusable $
+           "To use multiple 'library' sections or a named library section "
+        ++ "the package needs to specify at least 'cabal-version >= 1.23'."
+
     -- check use of reexported-modules sections
   , checkVersion [1,21]
-    (maybe False (not.null.reexportedModules) (library pkg)) $
+    (any (not.null.reexportedModules) (libraries pkg)) $
       PackageDistInexcusable $
            "To use the 'reexported-module' field the package needs to specify "
         ++ "at least 'cabal-version: >= 1.21'."
@@ -1312,7 +1331,7 @@ checkConditionals pkg =
     unknownOSs    = [ os   | OS   (OtherOS os)           <- conditions ]
     unknownArches = [ arch | Arch (OtherArch arch)       <- conditions ]
     unknownImpls  = [ impl | Impl (OtherCompiler impl) _ <- conditions ]
-    conditions = maybe [] fvs (condLibrary pkg)
+    conditions = concatMap (fvs . snd) (condLibraries pkg)
               ++ concatMap (fvs . snd) (condExecutables pkg)
     fvs (CondNode _ _ ifs) = concatMap compfv ifs -- free variables
     compfv (c, ct, mct) = condfv c ++ fvs ct ++ maybe [] fvs mct
@@ -1416,8 +1435,8 @@ checkDevelopmentOnlyFlags pkg =
 
     allConditionalBuildInfo :: [([Condition ConfVar], BuildInfo)]
     allConditionalBuildInfo =
-        concatMap (collectCondTreePaths libBuildInfo)
-                  (maybeToList (condLibrary pkg))
+        concatMap (collectCondTreePaths libBuildInfo . snd)
+                  (condLibraries pkg)
 
      ++ concatMap (collectCondTreePaths buildInfo . snd)
                   (condExecutables pkg)