Locate .ormolu file independently of .cabal files

Author: mrkkrp

CHANGELOG.md

@@ -10,6 +10,10 @@
   syntax), or on the command line with the `--reexport`/`-r` option. [Issue
   1017](https://github.com/tweag/ormolu/issues/1017).
 
+* Ormolu now looks for `.ormolu` files independently of `.cabal` files. This
+  means that it is now possible to have one `.ormolu` file for multiple
+  Cabal packages. [Issue 1019](https://github.com/tweag/ormolu/issues/1019).
+
 * Consistently format `do` blocks/`case`s/`MultiWayIf`s with 4 spaces if and
   only if they occur as the applicand. [Issue
   1002](https://github.com/tweag/ormolu/issues/1002) and [issue

README.md

@@ -162,15 +162,15 @@ project is formatted with Ormolu.
 ### Language extensions, dependencies, and fixities
 
 Ormolu automatically locates the Cabal file that corresponds to a given
-source code file. When input comes from stdin, one can pass
-`--stdin-input-file` which will give Ormolu the location of the Haskell
-source file that should be used as the starting point for searching for a
-suitable Cabal file. Cabal files are used to extract both default extensions
+source code file. Cabal files are used to extract both default extensions
 and dependencies. Default extensions directly affect behavior of the GHC
 parser, while dependencies are used to figure out fixities of operators that
-appear in the source code. Fixities can also be overridden if `.ormolu` file
-is found next to the corresponding Cabal file, i.e. they should be siblings
-in the same directory.
+appear in the source code. Fixities can also be overridden via an `.ormolu`
+file which should be located at a higher level in the file system hierarchy
+than the source file that is being formatted. When the input comes from
+stdin, one can pass `--stdin-input-file` which will give Ormolu the location
+that should be used as the starting point for searching for `.cabal` and
+`.ormolu` files.
 
 Here is an example of `.ormolu` file:
 
@@ -214,8 +214,8 @@ command line:
 * Fixities can be specified with the `-f` or `--fixity` flag.
 * Re-exports can be specified with the `-r` or `--reexport` flag.
 
-Searching for both `.cabal` and `.ormolu` files can be disabled by passing
-`--no-cabal`.
+Searching for `.cabal` and `.ormolu` files can be disabled by passing
+`--no-cabal` and `--no-dot-ormolu` respectively.
 
 ### Magic comments
 

app/Main.hs

@@ -40,7 +40,7 @@ main = do
   Opts {..} <- execParser optsParserInfo
   let formatOne' =
         formatOne
-          optCabal
+          optConfigFileOpts
           optMode
           optSourceType
           optConfig
@@ -67,7 +67,7 @@ main = do
 -- | Format a single input.
 formatOne ::
   -- | How to use .cabal files
-  CabalOpts ->
+  ConfigFileOpts ->
   -- | Mode of operation
   Mode ->
   -- | The 'SourceType' requested by the user
@@ -77,7 +77,7 @@ formatOne ::
   -- | File to format or stdin as 'Nothing'
   Maybe FilePath ->
   IO ExitCode
-formatOne CabalOpts {..} mode reqSourceType rawConfig mpath =
+formatOne ConfigFileOpts {..} mode reqSourceType rawConfig mpath =
   withPrettyOrmoluExceptions (cfgColorMode rawConfig) $ do
     let getCabalInfoForSourceFile' sourceFile = do
           cabalSearchResult <- getCabalInfoForSourceFile sourceFile
@@ -99,21 +99,24 @@ formatOne CabalOpts {..} mode reqSourceType rawConfig mpath =
                     <> sourceFile
               return (Just cabalInfo)
             CabalFound cabalInfo -> return (Just cabalInfo)
+        getDotOrmoluForSourceFile' sourceFile = do
+          if optDoNotUseDotOrmolu
+            then return Nothing
+            else Just <$> getDotOrmoluForSourceFile sourceFile
     case FP.normalise <$> mpath of
       -- input source = STDIN
       Nothing -> do
-        resultConfig <-
-          ( if optDoNotUseCabal
-              then pure Nothing
-              else case optStdinInputFile of
-                Just stdinInputFile ->
-                  getCabalInfoForSourceFile' stdinInputFile
-                Nothing -> throwIO OrmoluMissingStdinInputFile
-            )
-            >>= patchConfig Nothing
+        mcabalInfo <- case (optStdinInputFile, optDoNotUseCabal) of
+          (_, True) -> return Nothing
+          (Nothing, False) -> throwIO OrmoluMissingStdinInputFile
+          (Just inputFile, False) -> getCabalInfoForSourceFile' inputFile
+        mdotOrmolu <- case optStdinInputFile of
+          Nothing -> return Nothing
+          Just inputFile -> getDotOrmoluForSourceFile' inputFile
+        config <- patchConfig Nothing mcabalInfo mdotOrmolu
         case mode of
           Stdout -> do
-            ormoluStdin resultConfig >>= TIO.putStr
+            ormoluStdin config >>= TIO.putStr
             return ExitSuccess
           InPlace -> do
             hPutStrLn
@@ -126,41 +129,44 @@ formatOne CabalOpts {..} mode reqSourceType rawConfig mpath =
             originalInput <- getContentsUtf8
             let stdinRepr = "<stdin>"
             formattedInput <-
-              ormolu resultConfig stdinRepr originalInput
+              ormolu config stdinRepr originalInput
             handleDiff originalInput formattedInput stdinRepr
       -- input source = a file
       Just inputFile -> do
-        resultConfig <-
-          ( if optDoNotUseCabal
-              then pure Nothing
-              else getCabalInfoForSourceFile' inputFile
-            )
-            >>= patchConfig (Just (detectSourceType inputFile))
+        mcabalInfo <-
+          if optDoNotUseCabal
+            then return Nothing
+            else getCabalInfoForSourceFile' inputFile
+        mdotOrmolu <- getDotOrmoluForSourceFile' inputFile
+        config <-
+          patchConfig
+            (Just (detectSourceType inputFile))
+            mcabalInfo
+            mdotOrmolu
         case mode of
           Stdout -> do
-            ormoluFile resultConfig inputFile >>= TIO.putStr
+            ormoluFile config inputFile >>= TIO.putStr
             return ExitSuccess
           InPlace -> do
             -- ormoluFile is not used because we need originalInput
             originalInput <- readFileUtf8 inputFile
             formattedInput <-
-              ormolu resultConfig inputFile originalInput
+              ormolu config inputFile originalInput
             when (formattedInput /= originalInput) $
               writeFileUtf8 inputFile formattedInput
             return ExitSuccess
           Check -> do
             -- ormoluFile is not used because we need originalInput
             originalInput <- readFileUtf8 inputFile
             formattedInput <-
-              ormolu resultConfig inputFile originalInput
+              ormolu config inputFile originalInput
             handleDiff originalInput formattedInput inputFile
   where
-    patchConfig mdetectedSourceType mcabalInfo = do
+    patchConfig mdetectedSourceType mcabalInfo mdotOrmolu = do
       let sourceType =
             fromMaybe
               ModuleSource
               (reqSourceType <|> mdetectedSourceType)
-      mdotOrmolu <- traverse parseDotOrmoluForSourceFile mcabalInfo
       let mfixityOverrides = fst <$> mdotOrmolu
           mmoduleReexports = snd <$> mdotOrmolu
       return $
@@ -189,8 +195,8 @@ data Opts = Opts
     optMode :: !Mode,
     -- | Ormolu 'Config'
     optConfig :: !(Config RegionIndices),
-    -- | Options related to info extracted from .cabal files
-    optCabal :: CabalOpts,
+    -- | Options related to info extracted from files
+    optConfigFileOpts :: ConfigFileOpts,
     -- | Source type option, where 'Nothing' means autodetection
     optSourceType :: !(Maybe SourceType),
     -- | Haskell source files to format or stdin (when the list is empty)
@@ -208,10 +214,12 @@ data Mode
     Check
   deriving (Eq, Show)
 
--- | Configuration related to .cabal files.
-data CabalOpts = CabalOpts
+-- | Options related to configuration stored in the file system.
+data ConfigFileOpts = ConfigFileOpts
   { -- | DO NOT extract default-extensions and dependencies from .cabal files
     optDoNotUseCabal :: Bool,
+    -- | DO NOT look for @.ormolu@ files
+    optDoNotUseDotOrmolu :: Bool,
     -- | Optional path to a file which will be used to find a .cabal file
     -- when using input from stdin
     optStdinInputFile :: Maybe FilePath
@@ -262,21 +270,23 @@ optsParser =
               ]
         )
     <*> configParser
-    <*> cabalOptsParser
+    <*> configFileOptsParser
     <*> sourceTypeParser
     <*> (many . strArgument . mconcat)
       [ metavar "FILE",
         help "Haskell source files to format or stdin (the default)"
       ]
 
-cabalOptsParser :: Parser CabalOpts
-cabalOptsParser =
-  CabalOpts
+configFileOptsParser :: Parser ConfigFileOpts
+configFileOptsParser =
+  ConfigFileOpts
     <$> (switch . mconcat)
       [ long "no-cabal",
-        help $
-          "Do not extract default-extensions and dependencies from .cabal files"
-            ++ ", do not look for .ormolu files"
+        help "Do not extract default-extensions and dependencies from .cabal files"
+      ]
+    <*> (switch . mconcat)
+      [ long "no-dot-ormolu",
+        help "Do not look for .ormolu files"
       ]
     <*> (optional . strOption . mconcat)
       [ long "stdin-input-file",

fixity-tests/default.nix

@@ -11,25 +11,25 @@
     doCheck = true;
     buildPhase = ''
       cp test-0-input.hs test-0-no-extra-info.hs
-      ormolu --check-idempotence --mode inplace --no-cabal test-0-no-extra-info.hs
+      ormolu --check-idempotence --mode inplace --no-cabal --no-dot-ormolu test-0-no-extra-info.hs
       cp test-0-input.hs test-0-with-fixity-info-manual.hs
-      ormolu --check-idempotence --mode inplace --no-cabal --fixity 'infixr 8 .=' --fixity 'infixr 5 :>' test-0-with-fixity-info-manual.hs
+      ormolu --check-idempotence --mode inplace --no-cabal --no-dot-ormolu --fixity 'infixr 8 .=' --fixity 'infixr 5 :>' test-0-with-fixity-info-manual.hs
       cp test-0-input.hs test-0-with-fixity-info-dotormolu.hs
-      ormolu --check-idempotence --mode inplace -p base test-0-with-fixity-info-dotormolu.hs
+      ormolu --check-idempotence --mode inplace --no-cabal -p base test-0-with-fixity-info-dotormolu.hs
       cp test-1-input.hs test-1-no-extra-info.hs
-      ormolu --check-idempotence --mode inplace --no-cabal test-1-no-extra-info.hs
+      ormolu --check-idempotence --mode inplace --no-cabal --no-dot-ormolu test-1-no-extra-info.hs
       cp test-1-input.hs test-1-with-fixity-info-manual.hs
-      ormolu --check-idempotence --mode inplace --no-cabal --fixity 'infixr 8 .=' --fixity 'infixr 5 #' test-1-with-fixity-info-manual.hs
+      ormolu --check-idempotence --mode inplace --no-cabal --no-dot-ormolu --fixity 'infixr 8 .=' --fixity 'infixr 5 #' test-1-with-fixity-info-manual.hs
       cp test-1-input.hs test-1-with-fixity-info-dotormolu.hs
-      ormolu --check-idempotence --mode inplace -p base test-1-with-fixity-info-dotormolu.hs
+      ormolu --check-idempotence --mode inplace --no-cabal -p base test-1-with-fixity-info-dotormolu.hs
       cp test-1-input.hs test-1-with-fixity-info-weird-overwrite.hs
       ormolu --check-idempotence --mode inplace -p base --fixity "infixr 5 $" test-1-with-fixity-info-weird-overwrite.hs
       cp test-2-input.hs test-2-no-extra-info.hs
-      ormolu --check-idempotence --mode inplace --no-cabal -p base -p lens test-2-no-extra-info.hs
+      ormolu --check-idempotence --mode inplace --no-cabal --no-dot-ormolu -p base -p lens test-2-no-extra-info.hs
       cp test-2-input.hs test-2-reexports-manual.hs
-      ormolu --check-idempotence --mode inplace --no-cabal -p base -p lens --reexport 'module Foo exports Control.Lens' test-2-reexports-manual.hs
+      ormolu --check-idempotence --mode inplace --no-cabal --no-dot-ormolu -p base -p lens --reexport 'module Foo exports Control.Lens' test-2-reexports-manual.hs
       cp test-2-input.hs test-2-reexports-dotormolu.hs
-      ormolu --check-idempotence --mode inplace -p base -p lens test-2-reexports-dotormolu.hs
+      ormolu --check-idempotence --mode inplace --no-cabal -p base -p lens test-2-reexports-dotormolu.hs
     '';
     checkPhase = ''
       echo test-0-no-extra-info.hs

src/Ormolu.hs

@@ -29,7 +29,7 @@ module Ormolu
     defaultFixityOverrides,
     ModuleReexports,
     defaultModuleReexports,
-    parseDotOrmoluForSourceFile,
+    getDotOrmoluForSourceFile,
 
     -- * Working with exceptions
     OrmoluException (..),
@@ -59,7 +59,7 @@ import Ormolu.Parser.Result
 import Ormolu.Printer
 import Ormolu.Utils (showOutputable)
 import Ormolu.Utils.Cabal qualified as CabalUtils
-import Ormolu.Utils.Fixity (parseDotOrmoluForSourceFile)
+import Ormolu.Utils.Fixity (getDotOrmoluForSourceFile)
 import Ormolu.Utils.IO
 import System.FilePath
 

src/Ormolu/Utils/Cabal.hs

@@ -1,6 +1,5 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE RecordWildCards #-}
-{-# LANGUAGE ViewPatterns #-}
 
 module Ormolu.Utils.Cabal
   ( CabalSearchResult (..),
@@ -29,9 +28,9 @@ import Distribution.Utils.Path (getSymbolicPath)
 import Language.Haskell.Extension
 import Ormolu.Config
 import Ormolu.Exception
+import Ormolu.Utils.IO (findClosestFileSatisfying)
 import System.Directory
 import System.FilePath
-import System.IO.Error (isDoesNotExistError)
 import System.IO.Unsafe (unsafePerformIO)
 
 -- | The result of searching for a @.cabal@ file.
@@ -68,8 +67,8 @@ getCabalInfoForSourceFile ::
   FilePath ->
   -- | Extracted cabal info, if any
   m CabalSearchResult
-getCabalInfoForSourceFile sourceFile = liftIO $ do
-  findCabalFile sourceFile >>= \case
+getCabalInfoForSourceFile sourceFile =
+  liftIO (findCabalFile sourceFile) >>= \case
     Just cabalFile -> do
       (mentioned, cabalInfo) <- parseCabalInfo cabalFile sourceFile
       return
@@ -79,34 +78,16 @@ getCabalInfoForSourceFile sourceFile = liftIO $ do
         )
     Nothing -> return CabalNotFound
 
--- | Find the path to an appropriate .cabal file for a Haskell source file,
--- if available.
+-- | Find the path to an appropriate @.cabal@ file for a Haskell source
+-- file, if available.
 findCabalFile ::
   (MonadIO m) =>
-  -- | Path to a Haskell source file in a project with a .cabal file
+  -- | Path to a Haskell source file in a project with a @.cabal@ file
   FilePath ->
-  -- | Absolute path to the .cabal file if available
+  -- | Absolute path to the @.cabal@ file, if available
   m (Maybe FilePath)
-findCabalFile sourceFile = liftIO $ do
-  parentDir <- takeDirectory <$> makeAbsolute sourceFile
-  dirEntries <-
-    listDirectory parentDir `catch` \case
-      (isDoesNotExistError -> True) -> pure []
-      e -> throwIO e
-  let findDotCabal = \case
-        [] -> pure Nothing
-        e : es
-          | takeExtension e == ".cabal" ->
-              doesFileExist (parentDir </> e) >>= \case
-                True -> pure $ Just e
-                False -> findDotCabal es
-        _ : es -> findDotCabal es
-  findDotCabal dirEntries >>= \case
-    Just cabalFile -> pure . Just $ parentDir </> cabalFile
-    Nothing ->
-      if isDrive parentDir
-        then pure Nothing
-        else findCabalFile parentDir
+findCabalFile = findClosestFileSatisfying $ \x ->
+  takeExtension x == ".cabal"
 
 -- | Parsed cabal file information to be shared across multiple source files.
 data CachedCabalFile = CachedCabalFile
@@ -118,12 +99,12 @@ data CachedCabalFile = CachedCabalFile
   }
   deriving (Show)
 
--- | Cache ref that stores 'CachedCabalFile' per cabal file.
-cabalCacheRef :: IORef (Map FilePath CachedCabalFile)
-cabalCacheRef = unsafePerformIO $ newIORef M.empty
-{-# NOINLINE cabalCacheRef #-}
+-- | Cache ref that stores 'CachedCabalFile' per Cabal file.
+cacheRef :: IORef (Map FilePath CachedCabalFile)
+cacheRef = unsafePerformIO $ newIORef M.empty
+{-# NOINLINE cacheRef #-}
 
--- | Parse 'CabalInfo' from a .cabal file at the given 'FilePath'.
+-- | Parse 'CabalInfo' from a @.cabal@ file at the given 'FilePath'.
 parseCabalInfo ::
   (MonadIO m) =>
   -- | Location of the .cabal file
@@ -136,7 +117,7 @@ parseCabalInfo ::
 parseCabalInfo cabalFileAsGiven sourceFileAsGiven = liftIO $ do
   cabalFile <- makeAbsolute cabalFileAsGiven
   sourceFileAbs <- makeAbsolute sourceFileAsGiven
-  cabalCache <- readIORef cabalCacheRef
+  cabalCache <- readIORef cacheRef
   CachedCabalFile {..} <- whenNothing (M.lookup cabalFile cabalCache) $ do
     cabalFileBs <- B.readFile cabalFile
     genericPackageDescription <-
@@ -145,7 +126,7 @@ parseCabalInfo cabalFileAsGiven sourceFileAsGiven = liftIO $ do
     let extensionsAndDeps =
           getExtensionAndDepsMap cabalFile genericPackageDescription
         cachedCabalFile = CachedCabalFile {..}
-    atomicModifyIORef cabalCacheRef $
+    atomicModifyIORef cacheRef $
       (,cachedCabalFile) . M.insert cabalFile cachedCabalFile
   let (dynOpts, dependencies, mentioned) =
         case M.lookup (dropExtensions sourceFileAbs) extensionsAndDeps of