Distribution/PackageDescription/FieldGrammar.hs

    {-# LANGUAGE OverloadedStrings #-}
    -- | 'GenericPackageDescription' Field descriptions
    module Distribution.PackageDescription.FieldGrammar (
        -- * Package description
        packageDescriptionFieldGrammar,
        -- * Library
        libraryFieldGrammar,
        -- * Foreign library
        foreignLibFieldGrammar,
        -- * Executable
        executableFieldGrammar,
        -- * Test suite
        TestSuiteStanza (..),
        testSuiteFieldGrammar,
        validateTestSuite,
        unvalidateTestSuite,
        -- ** Lenses
        testStanzaTestType,
        testStanzaMainIs,
        testStanzaTestModule,
        testStanzaBuildInfo,
        -- * Benchmark
        BenchmarkStanza (..),
        benchmarkFieldGrammar,
        validateBenchmark,
        unvalidateBenchmark,
        -- ** Lenses
        benchmarkStanzaBenchmarkType,
        benchmarkStanzaMainIs,
        benchmarkStanzaBenchmarkModule,
        benchmarkStanzaBuildInfo,
        -- * Flag
        flagFieldGrammar,
        -- * Source repository
        sourceRepoFieldGrammar,
        -- * Setup build info
        setupBInfoFieldGrammar,
        -- * Component build info
        buildInfoFieldGrammar,
        ) where

    import Distribution.Compat.Lens
    import Distribution.Compat.Prelude
    import Prelude ()

    import Distribution.CabalSpecVersion
    import Distribution.Compiler                  (CompilerFlavor (..), PerCompilerFlavor (..))
    import Distribution.FieldGrammar
    import Distribution.ModuleName                (ModuleName)
    import Distribution.Package
    import Distribution.PackageDescription
    import Distribution.Parsec
    import Distribution.Parsec.Newtypes
    import Distribution.Fields
    import Distribution.Pretty                    (prettyShow)
    import Distribution.Types.ExecutableScope
    import Distribution.Types.ForeignLib
    import Distribution.Types.ForeignLibType
    import Distribution.Types.LibraryVisibility
    import Distribution.Types.UnqualComponentName
    import Distribution.Version                   (anyVersion)

    import qualified Distribution.SPDX as SPDX

    import qualified Distribution.Types.Lens as L

    -------------------------------------------------------------------------------
    -- PackageDescription
    -------------------------------------------------------------------------------

    packageDescriptionFieldGrammar
        :: (FieldGrammar g, Applicative (g PackageDescription), Applicative (g PackageIdentifier))
        => g PackageDescription PackageDescription
    packageDescriptionFieldGrammar = PackageDescription
        <$> optionalFieldDefAla "cabal-version" SpecVersion                L.specVersionRaw (Right anyVersion)
        <*> blurFieldGrammar L.package packageIdentifierGrammar
        <*> optionalFieldDefAla "license"       SpecLicense                L.licenseRaw (Left SPDX.NONE)
        <*> licenseFilesGrammar
        <*> freeTextFieldDef    "copyright"                                L.copyright
        <*> freeTextFieldDef    "maintainer"                               L.maintainer
        <*> freeTextFieldDef    "author"                                   L.author
        <*> freeTextFieldDef    "stability"                                L.stability
        <*> monoidalFieldAla    "tested-with"   (alaList' FSep TestedWith) L.testedWith
        <*> freeTextFieldDef    "homepage"                                 L.homepage
        <*> freeTextFieldDef    "package-url"                              L.pkgUrl
        <*> freeTextFieldDef    "bug-reports"                              L.bugReports
        <*> pure [] -- source-repos are stanza
        <*> freeTextFieldDef    "synopsis"                                 L.synopsis
        <*> freeTextFieldDef    "description"                              L.description
        <*> freeTextFieldDef    "category"                                 L.category
        <*> prefixedFields      "x-"                                       L.customFieldsPD
        <*> optionalField       "build-type"                               L.buildTypeRaw
        <*> pure Nothing -- custom-setup
        -- components
        <*> pure Nothing  -- lib
        <*> pure []       -- sub libs
        <*> pure []       -- executables
        <*> pure []       -- foreign libs
        <*> pure []       -- test suites
        <*> pure []       -- benchmarks
        --  * Files
        <*> monoidalFieldAla    "data-files"         (alaList' VCat FilePathNT) L.dataFiles
        <*> optionalFieldDefAla "data-dir"           FilePathNT                 L.dataDir ""
        <*> monoidalFieldAla    "extra-source-files" (alaList' VCat FilePathNT) L.extraSrcFiles
        <*> monoidalFieldAla    "extra-tmp-files"    (alaList' VCat FilePathNT) L.extraTmpFiles
        <*> monoidalFieldAla    "extra-doc-files"    (alaList' VCat FilePathNT) L.extraDocFiles
      where
        packageIdentifierGrammar = PackageIdentifier
            <$> uniqueField "name"    L.pkgName
            <*> uniqueField "version" L.pkgVersion

        licenseFilesGrammar = (++)
            -- TODO: neither field is deprecated
            -- should we pretty print license-file if there's single license file
            -- and license-files when more
            <$> monoidalFieldAla    "license-file"  (alaList' FSep FilePathNT)  L.licenseFiles
            <*> monoidalFieldAla    "license-files"  (alaList' FSep FilePathNT) L.licenseFiles
                ^^^ hiddenField

    -------------------------------------------------------------------------------
    -- Library
    -------------------------------------------------------------------------------

    libraryFieldGrammar
        :: (FieldGrammar g, Applicative (g Library), Applicative (g BuildInfo))
        => LibraryName
        -> g Library Library
    libraryFieldGrammar n = Library n
        <$> monoidalFieldAla  "exposed-modules"    (alaList' VCat MQuoted) L.exposedModules
        <*> monoidalFieldAla  "reexported-modules" (alaList  CommaVCat)    L.reexportedModules
        <*> monoidalFieldAla  "signatures"         (alaList' VCat MQuoted) L.signatures
            ^^^ availableSince CabalSpecV2_0 []
        <*> booleanFieldDef   "exposed"                                    L.libExposed True
        <*> visibilityField
        <*> blurFieldGrammar L.libBuildInfo buildInfoFieldGrammar
      where
        visibilityField = case n of
            -- nameless/"main" libraries are public
            LMainLibName -> pure LibraryVisibilityPublic
            -- named libraries have the field
            LSubLibName _ ->
                optionalFieldDef "visibility" L.libVisibility LibraryVisibilityPrivate
                ^^^ availableSince CabalSpecV3_0 LibraryVisibilityPrivate

    {-# SPECIALIZE libraryFieldGrammar :: LibraryName -> ParsecFieldGrammar' Library #-}
    {-# SPECIALIZE libraryFieldGrammar :: LibraryName -> PrettyFieldGrammar' Library #-}

    -------------------------------------------------------------------------------
    -- Foreign library
    -------------------------------------------------------------------------------

    foreignLibFieldGrammar
        :: (FieldGrammar g, Applicative (g ForeignLib), Applicative (g BuildInfo))
        => UnqualComponentName -> g ForeignLib ForeignLib
    foreignLibFieldGrammar n = ForeignLib n
        <$> optionalFieldDef "type"                                         L.foreignLibType ForeignLibTypeUnknown
        <*> monoidalFieldAla "options"           (alaList FSep)             L.foreignLibOptions
        <*> blurFieldGrammar L.foreignLibBuildInfo buildInfoFieldGrammar
        <*> optionalField    "lib-version-info"                             L.foreignLibVersionInfo
        <*> optionalField    "lib-version-linux"                            L.foreignLibVersionLinux
        <*> monoidalFieldAla "mod-def-file"      (alaList' FSep FilePathNT) L.foreignLibModDefFile
    {-# SPECIALIZE foreignLibFieldGrammar :: UnqualComponentName -> ParsecFieldGrammar' ForeignLib #-}
    {-# SPECIALIZE foreignLibFieldGrammar :: UnqualComponentName -> PrettyFieldGrammar' ForeignLib #-}

    -------------------------------------------------------------------------------
    -- Executable
    -------------------------------------------------------------------------------

    executableFieldGrammar
        :: (FieldGrammar g, Applicative (g Executable), Applicative (g BuildInfo))
        => UnqualComponentName -> g Executable Executable
    executableFieldGrammar n = Executable n
        -- main-is is optional as conditional blocks don't have it
        <$> optionalFieldDefAla "main-is" FilePathNT L.modulePath ""
        <*> optionalFieldDef    "scope"              L.exeScope ExecutablePublic
            ^^^ availableSince CabalSpecV2_0 ExecutablePublic
        <*> blurFieldGrammar L.buildInfo buildInfoFieldGrammar
    {-# SPECIALIZE executableFieldGrammar :: UnqualComponentName -> ParsecFieldGrammar' Executable #-}
    {-# SPECIALIZE executableFieldGrammar :: UnqualComponentName -> PrettyFieldGrammar' Executable #-}

    -------------------------------------------------------------------------------
    -- TestSuite
    -------------------------------------------------------------------------------

    -- | An intermediate type just used for parsing the test-suite stanza.
    -- After validation it is converted into the proper 'TestSuite' type.
    data TestSuiteStanza = TestSuiteStanza
        { _testStanzaTestType   :: Maybe TestType
        , _testStanzaMainIs     :: Maybe FilePath
        , _testStanzaTestModule :: Maybe ModuleName
        , _testStanzaBuildInfo  :: BuildInfo
        }

    instance L.HasBuildInfo TestSuiteStanza where
        buildInfo = testStanzaBuildInfo

    testStanzaTestType :: Lens' TestSuiteStanza (Maybe TestType)
    testStanzaTestType f s = fmap (\x -> s { _testStanzaTestType = x }) (f (_testStanzaTestType s))
    {-# INLINE testStanzaTestType #-}

    testStanzaMainIs :: Lens' TestSuiteStanza (Maybe FilePath)
    testStanzaMainIs f s = fmap (\x -> s { _testStanzaMainIs = x }) (f (_testStanzaMainIs s))
    {-# INLINE testStanzaMainIs #-}

    testStanzaTestModule :: Lens' TestSuiteStanza (Maybe ModuleName)
    testStanzaTestModule f s = fmap (\x -> s { _testStanzaTestModule = x }) (f (_testStanzaTestModule s))
    {-# INLINE testStanzaTestModule #-}

    testStanzaBuildInfo :: Lens' TestSuiteStanza BuildInfo
    testStanzaBuildInfo f s = fmap (\x -> s { _testStanzaBuildInfo = x }) (f (_testStanzaBuildInfo s))
    {-# INLINE testStanzaBuildInfo #-}

    testSuiteFieldGrammar
        :: (FieldGrammar g, Applicative (g TestSuiteStanza), Applicative (g BuildInfo))
        => g TestSuiteStanza TestSuiteStanza
    testSuiteFieldGrammar = TestSuiteStanza
        <$> optionalField    "type"                   testStanzaTestType
        <*> optionalFieldAla "main-is"     FilePathNT testStanzaMainIs
        <*> optionalField    "test-module"            testStanzaTestModule
        <*> blurFieldGrammar testStanzaBuildInfo buildInfoFieldGrammar

    validateTestSuite :: Position -> TestSuiteStanza -> ParseResult TestSuite
    validateTestSuite pos stanza = case _testStanzaTestType stanza of
        Nothing -> return $
            emptyTestSuite { testBuildInfo = _testStanzaBuildInfo stanza }

        Just tt@(TestTypeUnknown _ _) ->
            pure emptyTestSuite
                { testInterface = TestSuiteUnsupported tt
                , testBuildInfo = _testStanzaBuildInfo stanza
                }

        Just tt | tt `notElem` knownTestTypes ->
            pure emptyTestSuite
                { testInterface = TestSuiteUnsupported tt
                , testBuildInfo = _testStanzaBuildInfo stanza
                }

        Just tt@(TestTypeExe ver) -> case _testStanzaMainIs stanza of
            Nothing   -> do
                parseFailure pos (missingField "main-is" tt)
                pure emptyTestSuite
            Just file -> do
                when (isJust (_testStanzaTestModule stanza)) $
                    parseWarning pos PWTExtraBenchmarkModule (extraField "test-module" tt)
                pure emptyTestSuite
                    { testInterface = TestSuiteExeV10 ver file
                    , testBuildInfo = _testStanzaBuildInfo stanza
                    }

        Just tt@(TestTypeLib ver) -> case _testStanzaTestModule stanza of
             Nothing      -> do
                 parseFailure pos (missingField "test-module" tt)
                 pure emptyTestSuite
             Just module_ -> do
                when (isJust (_testStanzaMainIs stanza)) $
                    parseWarning pos PWTExtraMainIs (extraField "main-is" tt)
                pure emptyTestSuite
                    { testInterface = TestSuiteLibV09 ver module_
                    , testBuildInfo = _testStanzaBuildInfo stanza
                    }

      where
        missingField name tt = "The '" ++ name ++ "' field is required for the "
                            ++ prettyShow tt ++ " test suite type."

        extraField   name tt = "The '" ++ name ++ "' field is not used for the '"
                            ++ prettyShow tt ++ "' test suite type."

    unvalidateTestSuite :: TestSuite -> TestSuiteStanza
    unvalidateTestSuite t = TestSuiteStanza
        { _testStanzaTestType   = ty
        , _testStanzaMainIs     = ma
        , _testStanzaTestModule = mo
        , _testStanzaBuildInfo  = testBuildInfo t
        }
      where
        (ty, ma, mo) = case testInterface t of
            TestSuiteExeV10 ver file -> (Just $ TestTypeExe ver, Just file, Nothing)
            TestSuiteLibV09 ver modu -> (Just $ TestTypeLib ver, Nothing, Just modu)
            _                        -> (Nothing, Nothing, Nothing)

    -------------------------------------------------------------------------------
    -- Benchmark
    -------------------------------------------------------------------------------

    -- | An intermediate type just used for parsing the benchmark stanza.
    -- After validation it is converted into the proper 'Benchmark' type.
    data BenchmarkStanza = BenchmarkStanza
        { _benchmarkStanzaBenchmarkType   :: Maybe BenchmarkType
        , _benchmarkStanzaMainIs          :: Maybe FilePath
        , _benchmarkStanzaBenchmarkModule :: Maybe ModuleName
        , _benchmarkStanzaBuildInfo       :: BuildInfo
        }

    instance L.HasBuildInfo BenchmarkStanza where
        buildInfo = benchmarkStanzaBuildInfo

    benchmarkStanzaBenchmarkType :: Lens' BenchmarkStanza (Maybe BenchmarkType)
    benchmarkStanzaBenchmarkType f s = fmap (\x -> s { _benchmarkStanzaBenchmarkType = x }) (f (_benchmarkStanzaBenchmarkType s))
    {-# INLINE benchmarkStanzaBenchmarkType #-}

    benchmarkStanzaMainIs :: Lens' BenchmarkStanza (Maybe FilePath)
    benchmarkStanzaMainIs f s = fmap (\x -> s { _benchmarkStanzaMainIs = x }) (f (_benchmarkStanzaMainIs s))
    {-# INLINE benchmarkStanzaMainIs #-}

    benchmarkStanzaBenchmarkModule :: Lens' BenchmarkStanza (Maybe ModuleName)
    benchmarkStanzaBenchmarkModule f s = fmap (\x -> s { _benchmarkStanzaBenchmarkModule = x }) (f (_benchmarkStanzaBenchmarkModule s))
    {-# INLINE benchmarkStanzaBenchmarkModule #-}

    benchmarkStanzaBuildInfo :: Lens' BenchmarkStanza BuildInfo
    benchmarkStanzaBuildInfo f s = fmap (\x -> s { _benchmarkStanzaBuildInfo = x }) (f (_benchmarkStanzaBuildInfo s))
    {-# INLINE benchmarkStanzaBuildInfo #-}

    benchmarkFieldGrammar
        :: (FieldGrammar g, Applicative (g BenchmarkStanza), Applicative (g BuildInfo))
        => g BenchmarkStanza BenchmarkStanza
    benchmarkFieldGrammar = BenchmarkStanza
        <$> optionalField    "type"                        benchmarkStanzaBenchmarkType
        <*> optionalFieldAla "main-is"          FilePathNT benchmarkStanzaMainIs
        <*> optionalField    "benchmark-module"            benchmarkStanzaBenchmarkModule
        <*> blurFieldGrammar benchmarkStanzaBuildInfo buildInfoFieldGrammar

    validateBenchmark :: Position -> BenchmarkStanza -> ParseResult Benchmark
    validateBenchmark pos stanza = case _benchmarkStanzaBenchmarkType stanza of
        Nothing -> pure emptyBenchmark
            { benchmarkBuildInfo = _benchmarkStanzaBuildInfo stanza }

        Just tt@(BenchmarkTypeUnknown _ _) -> pure emptyBenchmark
            { benchmarkInterface = BenchmarkUnsupported tt
            , benchmarkBuildInfo = _benchmarkStanzaBuildInfo stanza
            }

        Just tt | tt `notElem` knownBenchmarkTypes -> pure emptyBenchmark
            { benchmarkInterface = BenchmarkUnsupported tt
            , benchmarkBuildInfo = _benchmarkStanzaBuildInfo stanza
            }

        Just tt@(BenchmarkTypeExe ver) -> case _benchmarkStanzaMainIs stanza of
            Nothing   -> do
                parseFailure pos (missingField "main-is" tt)
                pure emptyBenchmark
            Just file -> do
                when (isJust (_benchmarkStanzaBenchmarkModule stanza)) $
                    parseWarning pos PWTExtraBenchmarkModule (extraField "benchmark-module" tt)
                pure emptyBenchmark
                    { benchmarkInterface = BenchmarkExeV10 ver file
                    , benchmarkBuildInfo = _benchmarkStanzaBuildInfo stanza
                    }

      where
        missingField name tt = "The '" ++ name ++ "' field is required for the "
                            ++ prettyShow tt ++ " benchmark type."

        extraField   name tt = "The '" ++ name ++ "' field is not used for the '"
                            ++ prettyShow tt ++ "' benchmark type."

    unvalidateBenchmark :: Benchmark -> BenchmarkStanza
    unvalidateBenchmark b = BenchmarkStanza
        { _benchmarkStanzaBenchmarkType   = ty
        , _benchmarkStanzaMainIs          = ma
        , _benchmarkStanzaBenchmarkModule = mo
        , _benchmarkStanzaBuildInfo       = benchmarkBuildInfo b
        }
      where
        (ty, ma, mo) = case benchmarkInterface b of
            BenchmarkExeV10 ver ""  -> (Just $ BenchmarkTypeExe ver, Nothing,  Nothing)
            BenchmarkExeV10 ver ma' -> (Just $ BenchmarkTypeExe ver, Just ma', Nothing)
            _                       -> (Nothing, Nothing,  Nothing)

    -------------------------------------------------------------------------------
    -- Build info
    -------------------------------------------------------------------------------

    buildInfoFieldGrammar
        :: (FieldGrammar g, Applicative (g BuildInfo))
        => g BuildInfo BuildInfo
    buildInfoFieldGrammar = BuildInfo
        <$> booleanFieldDef  "buildable"                                          L.buildable True
        <*> monoidalFieldAla "build-tools"          (alaList  CommaFSep)          L.buildTools
            ^^^ deprecatedSince CabalSpecV2_0
                "Please use 'build-tool-depends' field"
            ^^^ removedIn CabalSpecV3_0
                "Please use 'build-tool-depends' field."
        <*> monoidalFieldAla "build-tool-depends"   (alaList  CommaFSep)          L.buildToolDepends
            -- {- ^^^ availableSince [2,0] [] -}
            -- here, we explicitly want to recognise build-tool-depends for all Cabal files
            -- as otherwise cabal new-build cannot really work.
            --
            -- I.e. we don't want trigger unknown field warning
        <*> monoidalFieldAla "cpp-options"          (alaList' NoCommaFSep Token') L.cppOptions
        <*> monoidalFieldAla "asm-options"          (alaList' NoCommaFSep Token') L.asmOptions
        <*> monoidalFieldAla "cmm-options"          (alaList' NoCommaFSep Token') L.cmmOptions
        <*> monoidalFieldAla "cc-options"           (alaList' NoCommaFSep Token') L.ccOptions
        <*> monoidalFieldAla "cxx-options"          (alaList' NoCommaFSep Token') L.cxxOptions
            ^^^ availableSince CabalSpecV2_2 []
        <*> monoidalFieldAla "ld-options"           (alaList' NoCommaFSep Token') L.ldOptions
        <*> monoidalFieldAla "pkgconfig-depends"    (alaList  CommaFSep)          L.pkgconfigDepends
        <*> monoidalFieldAla "frameworks"           (alaList' FSep Token)         L.frameworks
        <*> monoidalFieldAla "extra-framework-dirs" (alaList' FSep FilePathNT)    L.extraFrameworkDirs
        <*> monoidalFieldAla "asm-sources"          (alaList' VCat FilePathNT)    L.asmSources
        <*> monoidalFieldAla "cmm-sources"          (alaList' VCat FilePathNT)    L.cmmSources
        <*> monoidalFieldAla "c-sources"            (alaList' VCat FilePathNT)    L.cSources
        <*> monoidalFieldAla "cxx-sources"          (alaList' VCat FilePathNT)    L.cxxSources
            ^^^ availableSince CabalSpecV2_2 []
        <*> monoidalFieldAla "js-sources"           (alaList' VCat FilePathNT)    L.jsSources
        <*> hsSourceDirsGrammar
        <*> monoidalFieldAla "other-modules"        (alaList' VCat MQuoted)       L.otherModules
        <*> monoidalFieldAla "virtual-modules"      (alaList' VCat MQuoted)       L.virtualModules
            ^^^ availableSince CabalSpecV2_2 []
        <*> monoidalFieldAla "autogen-modules"      (alaList' VCat MQuoted)       L.autogenModules
        <*> optionalFieldAla "default-language"     MQuoted                       L.defaultLanguage
        <*> monoidalFieldAla "other-languages"      (alaList' FSep MQuoted)       L.otherLanguages
        <*> monoidalFieldAla "default-extensions"   (alaList' FSep MQuoted)       L.defaultExtensions
        <*> monoidalFieldAla "other-extensions"     (alaList' FSep MQuoted)       L.otherExtensions
        <*> monoidalFieldAla "extensions"           (alaList' FSep MQuoted)       L.oldExtensions
            ^^^ deprecatedSince CabalSpecV1_12
                "Please use 'default-extensions' or 'other-extensions' fields."
            ^^^ removedIn CabalSpecV3_0
                "Please use 'default-extensions' or 'other-extensions' fields."
        <*> monoidalFieldAla "extra-libraries"      (alaList' VCat Token)         L.extraLibs
        <*> monoidalFieldAla "extra-ghci-libraries" (alaList' VCat Token)         L.extraGHCiLibs
        <*> monoidalFieldAla "extra-bundled-libraries" (alaList' VCat Token)      L.extraBundledLibs
        <*> monoidalFieldAla "extra-library-flavours" (alaList' VCat Token)       L.extraLibFlavours
        <*> monoidalFieldAla "extra-dynamic-library-flavours" (alaList' VCat Token) L.extraDynLibFlavours
            ^^^ availableSince CabalSpecV3_0 []
        <*> monoidalFieldAla "extra-lib-dirs"       (alaList' FSep FilePathNT)    L.extraLibDirs
        <*> monoidalFieldAla "include-dirs"         (alaList' FSep FilePathNT)    L.includeDirs
        <*> monoidalFieldAla "includes"             (alaList' FSep FilePathNT)    L.includes
        <*> monoidalFieldAla "autogen-includes"     (alaList' FSep FilePathNT)    L.autogenIncludes
            ^^^ availableSince CabalSpecV3_0 []
        <*> monoidalFieldAla "install-includes"     (alaList' FSep FilePathNT)    L.installIncludes
        <*> optionsFieldGrammar
        <*> profOptionsFieldGrammar
        <*> sharedOptionsFieldGrammar
        <*> pure mempty -- static-options ???
        <*> prefixedFields   "x-"                                                 L.customFieldsBI
        <*> monoidalFieldAla "build-depends"        (alaList  CommaVCat)          L.targetBuildDepends
        <*> monoidalFieldAla "mixins"               (alaList  CommaVCat)          L.mixins
            ^^^ availableSince CabalSpecV2_0 []
    {-# SPECIALIZE buildInfoFieldGrammar :: ParsecFieldGrammar' BuildInfo #-}
    {-# SPECIALIZE buildInfoFieldGrammar :: PrettyFieldGrammar' BuildInfo #-}

    hsSourceDirsGrammar
        :: (FieldGrammar g, Applicative (g BuildInfo))
        => g BuildInfo [FilePath]
    hsSourceDirsGrammar = (++)
        <$> monoidalFieldAla "hs-source-dirs" (alaList' FSep FilePathNT) L.hsSourceDirs
        <*> monoidalFieldAla "hs-source-dir"  (alaList' FSep FilePathNT) wrongLens
            --- https://github.com/haskell/cabal/commit/49e3cdae3bdf21b017ccd42e66670ca402e22b44
            ^^^ deprecatedSince CabalSpecV1_2 "Please use 'hs-source-dirs'"
            ^^^ removedIn CabalSpecV3_0 "Please use 'hs-source-dirs' field."
      where
        -- TODO: make pretty printer aware of CabalSpecVersion
        wrongLens :: Functor f => LensLike' f BuildInfo [FilePath]
        wrongLens f bi = (\fps -> set L.hsSourceDirs fps bi) <$> f []

    optionsFieldGrammar
        :: (FieldGrammar g, Applicative (g BuildInfo))
        => g BuildInfo (PerCompilerFlavor [String])
    optionsFieldGrammar = PerCompilerFlavor
        <$> monoidalFieldAla "ghc-options"   (alaList' NoCommaFSep Token') (extract GHC)
        <*> monoidalFieldAla "ghcjs-options" (alaList' NoCommaFSep Token') (extract GHCJS)
        -- NOTE: Hugs, NHC and JHC are not supported anymore, but these
        -- fields are kept around so that we can still parse legacy .cabal
        -- files that have them.
        <*  knownField "jhc-options"
        <*  knownField "hugs-options"
        <*  knownField "nhc98-options"
      where
        extract :: CompilerFlavor -> ALens' BuildInfo [String]
        extract flavor = L.options . lookupLens flavor

    profOptionsFieldGrammar
        :: (FieldGrammar g, Applicative (g BuildInfo))
        => g BuildInfo (PerCompilerFlavor [String])
    profOptionsFieldGrammar = PerCompilerFlavor
        <$> monoidalFieldAla "ghc-prof-options"   (alaList' NoCommaFSep Token') (extract GHC)
        <*> monoidalFieldAla "ghcjs-prof-options" (alaList' NoCommaFSep Token') (extract GHCJS)
      where
        extract :: CompilerFlavor -> ALens' BuildInfo [String]
        extract flavor = L.profOptions . lookupLens flavor

    sharedOptionsFieldGrammar
        :: (FieldGrammar g, Applicative (g BuildInfo))
        => g BuildInfo (PerCompilerFlavor [String])
    sharedOptionsFieldGrammar = PerCompilerFlavor
        <$> monoidalFieldAla "ghc-shared-options"   (alaList' NoCommaFSep Token') (extract GHC)
        <*> monoidalFieldAla "ghcjs-shared-options" (alaList' NoCommaFSep Token') (extract GHCJS)
      where
        extract :: CompilerFlavor -> ALens' BuildInfo [String]
        extract flavor = L.sharedOptions . lookupLens flavor

    lookupLens :: (Functor f, Monoid v) => CompilerFlavor -> LensLike' f (PerCompilerFlavor v) v
    lookupLens k f p@(PerCompilerFlavor ghc ghcjs)
        | k == GHC   = (\n -> PerCompilerFlavor n ghcjs) <$> f ghc
        | k == GHCJS = (\n -> PerCompilerFlavor ghc n) <$> f ghcjs
        | otherwise  = p <$ f mempty

    -------------------------------------------------------------------------------
    -- Flag
    -------------------------------------------------------------------------------

    flagFieldGrammar
        :: (FieldGrammar g, Applicative (g Flag))
        =>  FlagName -> g Flag Flag
    flagFieldGrammar name = MkFlag name
        <$> freeTextFieldDef    "description"          L.flagDescription
        <*> booleanFieldDef     "default"              L.flagDefault     True
        <*> booleanFieldDef     "manual"               L.flagManual      False
    {-# SPECIALIZE flagFieldGrammar :: FlagName -> ParsecFieldGrammar' Flag #-}
    {-# SPECIALIZE flagFieldGrammar :: FlagName -> PrettyFieldGrammar' Flag #-}

    -------------------------------------------------------------------------------
    -- SourceRepo
    -------------------------------------------------------------------------------

    sourceRepoFieldGrammar
        :: (FieldGrammar g, Applicative (g SourceRepo))
        => RepoKind -> g SourceRepo SourceRepo
    sourceRepoFieldGrammar kind = SourceRepo kind
        <$> optionalField    "type"                L.repoType
        <*> freeTextField    "location"            L.repoLocation
        <*> optionalFieldAla "module"   Token      L.repoModule
        <*> optionalFieldAla "branch"   Token      L.repoBranch
        <*> optionalFieldAla "tag"      Token      L.repoTag
        <*> optionalFieldAla "subdir"   FilePathNT L.repoSubdir
    {-# SPECIALIZE sourceRepoFieldGrammar :: RepoKind -> ParsecFieldGrammar' SourceRepo #-}
    {-# SPECIALIZE sourceRepoFieldGrammar :: RepoKind ->PrettyFieldGrammar' SourceRepo #-}

    -------------------------------------------------------------------------------
    -- SetupBuildInfo
    -------------------------------------------------------------------------------

    setupBInfoFieldGrammar
        :: (FieldGrammar g, Functor (g SetupBuildInfo))
        => Bool -> g SetupBuildInfo SetupBuildInfo
    setupBInfoFieldGrammar def = flip SetupBuildInfo def
        <$> monoidalFieldAla "setup-depends" (alaList CommaVCat) L.setupDepends
    {-# SPECIALIZE setupBInfoFieldGrammar :: Bool -> ParsecFieldGrammar' SetupBuildInfo #-}
    {-# SPECIALIZE setupBInfoFieldGrammar :: Bool ->PrettyFieldGrammar' SetupBuildInfo #-}