Move the Config oracle to the library

See #347

hadrian.cabal

@@ -28,13 +28,13 @@ executable hadrian
                        , GHC
                        , Hadrian.Expression
                        , Hadrian.Oracles.ArgsHash
+                       , Hadrian.Oracles.Config
                        , Hadrian.Oracles.DirectoryContents
                        , Hadrian.Oracles.Path
                        , Hadrian.Target
                        , Hadrian.Utilities
-                       , Oracles.Config
-                       , Oracles.Config.Flag
-                       , Oracles.Config.Setting
+                       , Oracles.Flag
+                       , Oracles.Setting
                        , Oracles.Dependencies
                        , Oracles.ModuleFiles
                        , Oracles.PackageData

src/Expression.hs

@@ -40,7 +40,7 @@ import Stage
 import Target hiding (builder, inputs, outputs)
 import Way
 
-import Oracles.Config.Setting
+import Oracles.Setting
 
 -- | @Expr a@ is a computation that produces a value of type @Action a@ and can
 -- read parameters of the current build 'Target'.

src/Oracles/Config.hs → src/Hadrian/Oracles/Config.hs

 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
-module Oracles.Config (askConfig, unsafeAskConfig, configOracle) where
+module Hadrian.Oracles.Config (askConfig, unsafeAskConfig, configOracle) where
 
+import Control.Monad
 import qualified Data.HashMap.Strict as Map
+import Data.Maybe
+import Development.Shake
+import Development.Shake.Classes
 import Development.Shake.Config
 
-import Base
+import Hadrian.Utilities
 
 newtype ConfigKey = ConfigKey String
     deriving (Binary, Eq, Hashable, NFData, Show, Typeable)
 
+-- | Lookup a configuration setting raising an error if the key is not found.
 unsafeAskConfig :: String -> Action String
 unsafeAskConfig key = (fromMaybe $ error msg) <$> askConfig key
   where
     msg = "Key " ++ quote key ++ " not found in configuration files."
 
+-- | Lookup a configuration setting.
 askConfig :: String -> Action (Maybe String)
 askConfig = askOracle . ConfigKey
 
--- Oracle for configuration files
-configOracle :: Rules ()
-configOracle = void $ do
+-- | This oracle reads and parses a configuration file consisting of key-value
+-- pairs @key = value@ and answers 'askConfig' queries tracking the results.
+configOracle :: FilePath -> Rules ()
+configOracle configFile = void $ do
     cfg <- newCache $ \() -> do
         need [configFile]
         putLoud $ "Reading " ++ configFile ++ "..."

src/Oracles/Config/Flag.hs → src/Oracles/Flag.hs

-module Oracles.Config.Flag (
+module Oracles.Flag (
     Flag (..), flag, crossCompiling, platformSupportsSharedLibs,
     ghcWithSMP, ghcWithNativeCodeGen, supportsSplitObjects
     ) where
 
+import Hadrian.Oracles.Config
+
 import Base
-import Oracles.Config
-import Oracles.Config.Setting
+import Oracles.Setting
 
 data Flag = ArSupportsAtFile
           | CrossCompiling

src/Oracles/Config/Setting.hs → src/Oracles/Setting.hs

-module Oracles.Config.Setting (
+module Oracles.Setting (
     Setting (..), SettingList (..), setting, settingList,
     anyTargetPlatform, anyTargetOs, anyTargetArch, anyHostOs,
     ghcWithInterpreter, ghcEnableTablesNextToCode, useLibFFIForAdjustors,
@@ -6,8 +6,9 @@ module Oracles.Config.Setting (
     relocatableBuild, installDocDir, installGhcLibDir
     ) where
 
+import Hadrian.Oracles.Config
+
 import Base
-import Oracles.Config
 import Stage
 
 -- TODO: Reduce the variety of similar flags (e.g. CPP and non-CPP versions).
@@ -202,8 +203,9 @@ relocatableBuild = windowsHost
 
 installDocDir :: Action String
 installDocDir = do
-  version <- setting ProjectVersion
-  (-/- ("doc/ghc-" ++ version)) <$> setting InstallDataRootDir
+    version <- setting ProjectVersion
+    dataDir <- setting InstallDataRootDir
+    return $ dataDir -/- ("doc/ghc-" ++ version)
 
 -- ref: mk/install.mk:101
 -- TODO: CroosCompilePrefix
@@ -211,9 +213,9 @@ installDocDir = do
 -- subdirectory with the version number included.
 installGhcLibDir :: Action String
 installGhcLibDir = do
-  r <- relocatableBuild
-  libdir <- setting InstallLibDir
-  if r then return libdir
-       else do
-         v <- setting ProjectVersion
-         return $ libdir -/- ("ghc-" ++ v)
+    rBuild <- relocatableBuild
+    libdir <- setting InstallLibDir
+    if rBuild then return libdir
+         else do
+             version <- setting ProjectVersion
+             return $ libdir -/- ("ghc-" ++ version)

src/Rules/Data.hs

@@ -4,8 +4,8 @@ import Base
 import Context
 import Expression
 import GHC
-import Oracles.Config.Setting
 import Oracles.Dependencies
+import Oracles.Setting
 import Rules.Generate
 import Settings.Path
 import Target

src/Rules/Generate.hs

@@ -10,9 +10,9 @@ import Context hiding (package)
 import Expression
 import Flavour
 import GHC
-import Oracles.Config.Flag
-import Oracles.Config.Setting
+import Oracles.Flag
 import Oracles.ModuleFiles
+import Oracles.Setting
 import Rules.Libffi
 import Settings
 import Settings.Path

src/Rules/Gmp.hs

@@ -5,7 +5,7 @@ import Hadrian.Utilities
 import Base
 import Builder
 import GHC
-import Oracles.Config.Setting
+import Oracles.Setting
 import Package
 import Settings.Packages.IntegerGmp
 import Settings.Path

src/Rules/Install.hs

@@ -2,24 +2,23 @@
 module Rules.Install (installRules) where
 
 import Hadrian.Oracles.DirectoryContents
+import qualified System.Directory as IO
 
 import Base
-import Expression hiding (builder)
-import Target
 import Context
-import Settings
-import Settings.Path
-import Util
+import Expression hiding (builder)
 import GHC
+import Oracles.Dependencies
+import Oracles.Setting
 import Rules
 import Rules.Generate
 import Rules.Libffi
 import Rules.Wrappers
+import Settings
 import Settings.Packages.Rts
-import Oracles.Config.Setting
-import Oracles.Dependencies
-
-import qualified System.Directory as IO
+import Settings.Path
+import Target
+import Util
 
 {- | Install the built binaries etc. to the @destDir ++ prefix@.
 

src/Rules/Oracles.hs

 module Rules.Oracles (oracleRules) where
 
 import qualified Hadrian.Oracles.ArgsHash
+import qualified Hadrian.Oracles.Config
 import qualified Hadrian.Oracles.DirectoryContents
 import qualified Hadrian.Oracles.Path
 
 import Base
-import qualified Oracles.Config
 import qualified Oracles.Dependencies
 import qualified Oracles.ModuleFiles
 import qualified Oracles.PackageData
@@ -15,9 +15,9 @@ import Settings
 oracleRules :: Rules ()
 oracleRules = do
     Hadrian.Oracles.ArgsHash.argsHashOracle trackArgument getArgs
+    Hadrian.Oracles.Config.configOracle configFile
     Hadrian.Oracles.DirectoryContents.directoryContentsOracle
     Hadrian.Oracles.Path.pathOracle
-    Oracles.Config.configOracle
     Oracles.Dependencies.dependenciesOracles
     Oracles.ModuleFiles.moduleFilesOracle
     Oracles.PackageData.packageDataOracle

src/Rules/Program.hs

@@ -6,10 +6,10 @@ import Base
 import Context
 import Expression hiding (stage, way)
 import GHC
-import Oracles.Config.Setting
 import Oracles.Dependencies
 import Oracles.ModuleFiles
 import Oracles.PackageData
+import Oracles.Setting
 import Rules.Wrappers
 import Settings
 import Settings.Path

src/Rules/Selftest.hs

@@ -9,8 +9,8 @@ import Test.QuickCheck
 import Base
 import Expression
 import GHC
-import Oracles.Config.Setting
 import Oracles.ModuleFiles
+import Oracles.Setting
 import Settings
 import Settings.Builders.Ar
 import Target

src/Rules/SourceDist.hs

@@ -4,7 +4,7 @@ import Hadrian.Oracles.DirectoryContents
 
 import Base
 import Builder
-import Oracles.Config.Setting
+import Oracles.Setting
 import Rules.Clean
 import UserSettings
 import Util

src/Rules/Test.hs

@@ -7,8 +7,8 @@ import Builder
 import Expression
 import Flavour
 import GHC
-import Oracles.Config.Flag
-import Oracles.Config.Setting
+import Oracles.Flag
+import Oracles.Setting
 import Settings
 import Settings.Path
 import Target

src/Rules/Wrappers.hs

@@ -5,7 +5,7 @@ module Rules.Wrappers (
 import Base
 import Expression
 import GHC
-import Oracles.Config.Setting
+import Oracles.Setting
 import Settings
 import Settings.Install
 import Settings.Path

src/Settings.hs

@@ -6,6 +6,7 @@ module Settings (
     integerLibraryName, destDir, pkgConfInstallPath, stage1Only
     ) where
 
+import Hadrian.Oracles.Config
 import Hadrian.Oracles.Path
 
 import Base
@@ -14,7 +15,6 @@ import CmdLineFlag
 import Expression
 import Flavour
 import GHC
-import Oracles.Config
 import Oracles.PackageData
 import {-# SOURCE #-} Settings.Default
 import Settings.Flavours.Development

src/Settings/Builders/Common.hs

@@ -2,9 +2,9 @@ module Settings.Builders.Common (
     module Base,
     module Expression,
     module GHC,
-    module Oracles.Config.Flag,
-    module Oracles.Config.Setting,
+    module Oracles.Flag,
     module Oracles.PackageData,
+    module Oracles.Setting,
     module Settings,
     module Settings.Path,
     module UserSettings,
@@ -14,9 +14,9 @@ module Settings.Builders.Common (
 import Base
 import Expression
 import GHC
-import Oracles.Config.Flag
-import Oracles.Config.Setting
+import Oracles.Flag
 import Oracles.PackageData
+import Oracles.Setting
 import Settings
 import Settings.Path
 import UserSettings

src/Settings/Default.hs

@@ -8,9 +8,9 @@ import CmdLineFlag
 import Expression
 import Flavour
 import GHC
-import Oracles.Config.Flag
-import Oracles.Config.Setting
+import Oracles.Flag
 import Oracles.PackageData
+import Oracles.Setting
 import Settings
 import Settings.Builders.Alex
 import Settings.Builders.Ar

src/Settings/Flavours/Quick.hs

@@ -2,7 +2,7 @@ module Settings.Flavours.Quick (quickFlavour) where
 
 import Flavour
 import Expression
-import Oracles.Config.Flag (platformSupportsSharedLibs)
+import Oracles.Flag
 import {-# SOURCE #-} Settings.Default
 
 quickFlavour :: Flavour

src/Settings/Packages/Compiler.hs

@@ -4,8 +4,8 @@ import Base
 import Expression
 import Flavour
 import GHC
-import Oracles.Config.Flag
-import Oracles.Config.Setting
+import Oracles.Flag
+import Oracles.Setting
 import Settings
 
 compilerPackageArgs :: Args