Handle Paths_* module

hpack.cabal

@@ -38,12 +38,12 @@ library
       Hpack.Config
       Hpack.Run
       Hpack.Yaml
-      Paths_hpack
   other-modules:
       Hpack.GenericsUtil
       Hpack.Haskell
       Hpack.Render
       Hpack.Util
+      Paths_hpack
   default-language: Haskell2010
 
 executable hpack

package.yaml

@@ -28,7 +28,6 @@ library:
     - Hpack.Config
     - Hpack.Run
     - Hpack.Yaml
-    - Paths_hpack
 
 executables:
   hpack:

src/Hpack/Config.hs

@@ -26,6 +26,7 @@ module Hpack.Config (
 , SourceRepository(..)
 #ifdef TEST
 , getModules
+, determineModules
 #endif
 ) where
 
@@ -291,13 +292,13 @@ data SourceRepository = SourceRepository {
 
 mkPackage :: (CaptureUnknownFields (Section PackageConfig)) -> IO ([String], Package)
 mkPackage (CaptureUnknownFields unknownFields globalOptions@Section{sectionData = PackageConfig{..}}) = do
-  mLibrary <- mapM (toLibrary globalOptions) mLibrarySection
+  name <- maybe (takeBaseName <$> getCurrentDirectory) return packageConfigName
+
+  mLibrary <- mapM (toLibrary name globalOptions) mLibrarySection
   executables <- toExecutables globalOptions (map (fmap captureUnknownFieldsValue) executableSections)
   tests <- toExecutables globalOptions (map (fmap captureUnknownFieldsValue) testsSections)
   benchmarks <- toExecutables globalOptions  (map (fmap captureUnknownFieldsValue) benchmarkSections)
 
-  name <- maybe (takeBaseName <$> getCurrentDirectory) return packageConfigName
-
   licenseFileExists <- doesFileExist "LICENSE"
 
   missingSourceDirs <- nub . sort <$> filterM (fmap not <$> doesDirectoryExist) (
@@ -401,8 +402,8 @@ mkPackage (CaptureUnknownFields unknownFields globalOptions@Section{sectionData
       where
         fromGithub = (++ "/issues") . sourceRepositoryUrl <$> sourceRepository
 
-toLibrary :: Section global -> Section LibrarySection -> IO (Section Library)
-toLibrary globalOptions library = traverse fromLibrarySection sect
+toLibrary :: String -> Section global -> Section LibrarySection -> IO (Section Library)
+toLibrary name globalOptions library = traverse fromLibrarySection sect
   where
     sect :: Section LibrarySection
     sect = mergeSections globalOptions library
@@ -413,7 +414,7 @@ toLibrary globalOptions library = traverse fromLibrarySection sect
     fromLibrarySection :: LibrarySection -> IO Library
     fromLibrarySection LibrarySection{..} = do
       modules <- concat <$> mapM getModules sourceDirs
-      let (exposedModules, otherModules) = determineModules modules librarySectionExposedModules librarySectionOtherModules
+      let (exposedModules, otherModules) = determineModules name modules librarySectionExposedModules librarySectionOtherModules
       return (Library exposedModules otherModules)
 
 toExecutables :: Section global -> [(String, Section ExecutableSection)] -> IO [Section Executable]
@@ -462,13 +463,14 @@ toSection a CommonOptions{..}
     cppOptions = fromMaybeList commonOptionsCppOptions
     dependencies = fromMaybeList commonOptionsDependencies
 
-determineModules :: [String] -> Maybe (List String) -> Maybe (List String) -> ([String], [String])
-determineModules modules mExposedModules mOtherModules = case (mExposedModules, mOtherModules) of
+determineModules :: String -> [String] -> Maybe (List String) -> Maybe (List String) -> ([String], [String])
+determineModules name modules mExposedModules mOtherModules = case (mExposedModules, mOtherModules) of
   (Nothing, Nothing) -> (modules, [])
   _ -> (exposedModules, otherModules)
   where
-    otherModules   = maybe (modules \\ exposedModules) fromList mOtherModules
+    otherModules   = maybe ((modules \\ exposedModules) ++ pathsModule) fromList mOtherModules
     exposedModules = maybe (modules \\ otherModules)   fromList mExposedModules
+    pathsModule = ["Paths_" ++ name] \\ exposedModules
 
 getModules :: FilePath -> IO [String]
 getModules src_ = sort <$> do

test/Hpack/ConfigSpec.hs

@@ -15,6 +15,7 @@ import           Data.Aeson.QQ
 import           Data.Aeson.Types
 import           Data.String.Interpolate
 
+import           Hpack.Util
 import           Hpack.Config hiding (package)
 import qualified Hpack.Config as Config
 
@@ -102,6 +103,14 @@ spec = do
         touch "Setup.hs"
         getModules "./." `shouldReturn` ["Foo"]
 
+  describe "determineModules" $ do
+    it "adds the Paths_* module to the other-modules" $ do
+      determineModules "foo" [] (Just $ List ["Foo"]) Nothing `shouldBe` (["Foo"], ["Paths_foo"])
+
+    context "when the Paths_* module is part of the exposed-modules" $ do
+      it "it does not add the Paths_* module to the other-modules" $ do
+        determineModules "foo" [] (Just $ List ["Foo", "Paths_foo"]) Nothing `shouldBe` (["Foo", "Paths_foo"], [])
+
   describe "readPackageConfig" $ around_ (inTempDirectoryNamed "foo") $ do
     it "warns on unknown fields" $ do
       writeFile "package.yaml" [i|
@@ -360,7 +369,7 @@ spec = do
         touch "src/Foo.hs"
         touch "src/Bar.hs"
         Right (_, c) <- readPackageConfig "package.yaml"
-        packageLibrary c `shouldBe` Just (section library{libraryExposedModules = ["Foo"], libraryOtherModules = ["Bar"]}) {sectionSourceDirs = ["src"]}
+        packageLibrary c `shouldBe` Just (section library{libraryExposedModules = ["Foo"], libraryOtherModules = ["Bar", "Paths_foo"]}) {sectionSourceDirs = ["src"]}
 
       it "allows to specify other-modules" $ do
         writeFile "package.yaml" [i|