Don't use String for operator and package names

app/Main.hs

@@ -24,7 +24,7 @@ import Language.Haskell.TH.Env (envQ)
 import Options.Applicative
 import Ormolu
 import Ormolu.Diff.Text (diffText, printTextDiff)
-import Ormolu.Fixity (FixityInfo)
+import Ormolu.Fixity (FixityInfo, OpName)
 import Ormolu.Parser (manualExts)
 import Ormolu.Terminal
 import Ormolu.Utils (showOutputable)
@@ -359,7 +359,7 @@ parseMode = eitherReader $ \case
   s -> Left $ "unknown mode: " ++ s
 
 -- | Parse a fixity declaration.
-parseFixityDeclaration :: ReadM [(String, FixityInfo)]
+parseFixityDeclaration :: ReadM [(OpName, FixityInfo)]
 parseFixityDeclaration = eitherReader parseFixityDeclarationStr
 
 -- | Parse 'ColorMode'.

extract-hackage-info/extract-hackage-info.cabal

@@ -10,6 +10,7 @@ executable extract-hackage-info
     default-language: Haskell2010
     ghc-options:      -O2 -Wall -rtsopts -Wunused-packages
     build-depends:
+        Cabal-syntax >=3.8 && <3.9,
         base >=4.12 && <5.0,
         binary >=0.8 && <0.9,
         bytestring >=0.10 && <0.12,

extract-hackage-info/src/Main.hs

@@ -31,6 +31,7 @@ import qualified Data.Text as T
 import Data.Text.Encoding (decodeLatin1)
 import qualified Data.Text.IO as TIO
 import Data.Void (Void)
+import Distribution.Types.PackageName (PackageName, mkPackageName, unPackageName)
 import Formatting
 import Options.Applicative
 import Ormolu.Fixity hiding (packageToOps, packageToPopularity)
@@ -61,7 +62,7 @@ data State = State
     -- conflicting fixity declarations for a same operator
     -- (called self-conflicts), and we want to emit a warning message later
     -- for these
-    sPackageToOps :: Map String (Map String [FixityInfo]),
+    sPackageToOps :: Map PackageName (Map OpName [FixityInfo]),
     -- | How many Hoogle files have been processed
     sProcessedFiles :: Int
   }
@@ -103,7 +104,7 @@ getPackageName ::
   -- | Path to the Hoogle file
   FilePath ->
   -- | Package name extracted from the Hoogle file
-  IO Text
+  IO PackageName
 getPackageName rootPath filePath = do
   unless (rootPath `isPrefixOf` filePath) $
     exitWithMsg $
@@ -119,7 +120,7 @@ getPackageName rootPath filePath = do
         ("Extracted package name is empty for " % string % " (base path = " % string % ")")
         filePath
         rootPath
-  return packageName
+  pure . mkPackageName . T.unpack $ packageName
 
 -- | Try to read the specified file using utf-8 encoding first,
 -- and latin1 otherwise.
@@ -137,47 +138,46 @@ readFileUtf8Latin1 filePath = catch @IOException (TIO.readFile filePath) $
 -- e.g. @(+) :: Num a => a -> a -> a@, update the fixity map accordingly.
 onSymbolDecl ::
   -- | Name of the package in which the symbol declaration was found
-  Text ->
+  PackageName ->
   -- | Symbol name extracted from the symbol declaration in the Hoogle file
-  String ->
+  OpName ->
   -- | Current state
   State ->
   -- | Updated state
   State
 onSymbolDecl packageName declOpName state@State {..} =
-  let sPackageToOps' = case Map.lookup packageName' sPackageToOps of
+  let sPackageToOps' = case Map.lookup packageName sPackageToOps of
         Nothing ->
           Map.insert
-            packageName'
+            packageName
             (Map.singleton declOpName [])
             sPackageToOps
         Just packageFixityMap ->
           case Map.lookup declOpName packageFixityMap of
             Nothing ->
               Map.insert
-                packageName'
+                packageName
                 (Map.insert declOpName [] packageFixityMap)
                 sPackageToOps
             Just _ -> sPackageToOps
-      packageName' = T.unpack packageName
    in state {sPackageToOps = sPackageToOps'}
 
 -- | When a fixity declaration is encountered, e.g. @infixr 5 :@, update the
 -- fixity map accordingly.
 onFixityDecl ::
   -- | Name of the package in which the symbol declaration was found
-  Text ->
+  PackageName ->
   -- | Tuple of operator name and fixity info
-  (String, FixityInfo) ->
+  (OpName, FixityInfo) ->
   -- | Current state
   State ->
   -- | Updated state
   State
 onFixityDecl packageName (opName, fixDecl) state@State {..} =
-  let sPackageToOps' = case Map.lookup packageName' sPackageToOps of
+  let sPackageToOps' = case Map.lookup packageName sPackageToOps of
         Nothing ->
           Map.insert
-            packageName'
+            packageName
             (Map.singleton opName [fixDecl])
             sPackageToOps
         Just packageFixityMap ->
@@ -187,21 +187,20 @@ onFixityDecl packageName (opName, fixDecl) state@State {..} =
                   sPackageToOps
             fixDecls ->
               Map.insert
-                packageName'
+                packageName
                 ( Map.insert
                     opName
                     (fixDecl : fixDecls)
                     packageFixityMap
                 )
                 sPackageToOps
-      packageName' = T.unpack packageName
    in state {sPackageToOps = sPackageToOps'}
 
 -- | Represent an operator for which we found conflicting definitions
 -- originating from the same package.
 data SelfConflict = SelfConflict
-  { scPackageName :: String,
-    scOperatorName :: String,
+  { scPackageName :: PackageName,
+    scOperatorName :: OpName,
     scConflictingDefs :: [FixityInfo]
   }
 
@@ -210,8 +209,8 @@ data SelfConflict = SelfConflict
 -- (where conflicting definitions from self-conflicts are merged), and also
 -- return the list of self-conflicts
 finalizePackageToOps ::
-  Map String (Map String [FixityInfo]) ->
-  (Map String (Map String FixityInfo), [SelfConflict])
+  Map PackageName (Map OpName [FixityInfo]) ->
+  (Map PackageName (Map OpName FixityInfo), [SelfConflict])
 finalizePackageToOps hashmap =
   ( Map.map (Map.map finalize) hashmap,
     concatMap injectFst
@@ -252,9 +251,9 @@ extractFixitiesFromFile
 -- | The types of declarations in the Hoogle files we are interested in.
 data DeclType
   = -- | See third argument of 'onSymbolDecl'.
-    SymbolDecl String
+    SymbolDecl OpName
   | -- | See third argument of 'onFixityDecl'.
-    FixityDecl (String, FixityInfo)
+    FixityDecl (OpName, FixityInfo)
 
 -- | Parse all 'DeclType's in some file content.
 parseDecls :: Text -> [DeclType]
@@ -278,7 +277,7 @@ parseDecls = either mempty id . MP.runParser pDecls ""
 extractHoogleInfo ::
   -- | Path to the hoogle directory containing all package directories
   FilePath ->
-  IO (Map String FixityMap)
+  IO (Map PackageName FixityMap)
 extractHoogleInfo hoogleDatabasePath = do
   hoogleFiles <- walkDir hoogleDatabasePath
   State {..} <-
@@ -315,12 +314,12 @@ displaySelfConflicts selfConflicts =
     showSc SelfConflict {scPackageName, scOperatorName, scConflictingDefs} =
       sformat
         ("(in " % string % ") " % string)
-        scPackageName
-        scOperatorName
+        (unPackageName scPackageName)
+        (T.unpack $ unOpName scOperatorName)
         : indentLines (showT <$> scConflictingDefs)
 
 -- | Display stats about the Hoogle database processing.
-displayFixityStats :: Map String FixityMap -> IO ()
+displayFixityStats :: Map PackageName FixityMap -> IO ()
 displayFixityStats packageToOps =
   hprintLn
     stdout
@@ -348,7 +347,7 @@ extractHackageInfo ::
   -- | Path to the Hackage HTML page
   FilePath ->
   -- | Map packageName -> download count
-  IO (Map String Int)
+  IO (Map PackageName Int)
 extractHackageInfo filePath = do
   content <- TIO.readFile filePath
   let soup = filterBlankTags $ parseTags content
@@ -357,7 +356,7 @@ extractHackageInfo filePath = do
           takeWhile (not . tagCloseLit "table") $
             dropWhile (not . tagOpenLit "table" (const True)) soup
       processRow tags = case extractText <$> groupOn "td" tags of
-        rawName : rawDlCount : _ -> return $ Just (name, dlCount)
+        rawName : rawDlCount : _ -> return $ Just (mkPackageName name, dlCount)
           where
             name = T.unpack . T.strip . head $ T.split (== ' ') rawName
             dlCount = readT $ T.strip rawDlCount :: Int

ormolu.cabal

@@ -161,6 +161,7 @@ test-suite tests
 
     default-language:   Haskell2010
     build-depends:
+        Cabal-syntax >=3.8 && <3.9,
         QuickCheck >=2.14,
         base >=4.14 && <5.0,
         containers >=0.5 && <0.7,

src/Ormolu/Config.hs

@@ -19,6 +19,7 @@ where
 import qualified Data.Map.Strict as Map
 import Data.Set (Set)
 import qualified Data.Set as Set
+import Distribution.Types.PackageName (PackageName)
 import GHC.Generics (Generic)
 import qualified GHC.Types.SrcLoc as GHC
 import Ormolu.Fixity (FixityMap)
@@ -39,7 +40,7 @@ data Config region = Config
     -- | Fixity overrides
     cfgFixityOverrides :: FixityMap,
     -- | Known dependencies, if any
-    cfgDependencies :: !(Set String),
+    cfgDependencies :: !(Set PackageName),
     -- | Do formatting faster but without automatic detection of defects
     cfgUnsafe :: !Bool,
     -- | Output information useful for debugging

src/Ormolu/Fixity.hs

@@ -1,10 +1,16 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE MultiWayIf #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE TemplateHaskell #-}
 
 -- | Definitions for fixity analysis.
 module Ormolu.Fixity
-  ( FixityDirection (..),
+  ( OpName,
+    pattern OpName,
+    unOpName,
+    occOpName,
+    FixityDirection (..),
     FixityInfo (..),
     FixityMap,
     LazyFixityMap,
@@ -30,14 +36,15 @@ import qualified Data.List.NonEmpty as NE
 import Data.Map.Strict (Map)
 import qualified Data.Map.Strict as Map
 import Data.Maybe (fromMaybe)
-import Data.MemoTrie (HasTrie, memo)
+import Data.MemoTrie (memo)
 import Data.Semigroup (sconcat)
 import Data.Set (Set)
 import qualified Data.Set as Set
+import Distribution.Types.PackageName (PackageName, mkPackageName, unPackageName)
 import Ormolu.Fixity.Internal
 
-packageToOps :: Map String FixityMap
-packageToPopularity :: Map String Int
+packageToOps :: Map PackageName FixityMap
+packageToPopularity :: Map PackageName Int
 HackageInfo packageToOps packageToPopularity =
   Binary.runGet Binary.get $
     BL.fromStrict $(embedFile "extract-hackage-info/hackage-info.bin")
@@ -47,7 +54,7 @@ HackageInfo packageToOps packageToPopularity =
 -- See https://github.com/tweag/ormolu/pull/830#issuecomment-986609572.
 -- "base" is not is this list, because it is already whitelisted
 -- by buildFixityMap'.
-bootPackages :: Set String
+bootPackages :: Set PackageName
 bootPackages =
   Set.fromList
     [ "array",
@@ -87,7 +94,7 @@ buildFixityMap ::
   -- instead of being merged with them
   Float ->
   -- | Explicitly known dependencies
-  Set String ->
+  Set PackageName ->
   -- | Resulting map
   LazyFixityMap
 buildFixityMap = buildFixityMap' packageToOps packageToPopularity bootPackages
@@ -98,17 +105,17 @@ buildFixityMap = buildFixityMap' packageToOps packageToPopularity bootPackages
 -- specify the package databases used to build the final fixity map.
 buildFixityMap' ::
   -- | Map from package to fixity map for operators defined in this package
-  Map String FixityMap ->
+  Map PackageName FixityMap ->
   -- | Map from package to popularity
-  Map String Int ->
+  Map PackageName Int ->
   -- | Higher priority packages
-  Set String ->
+  Set PackageName ->
   -- | Popularity ratio threshold, after which a very popular package will
   -- completely rule out conflicting definitions coming from other packages
   -- instead of being merged with them
   Float ->
   -- | Explicitly known dependencies
-  Set String ->
+  Set PackageName ->
   -- | Resulting map
   LazyFixityMap
 buildFixityMap'
@@ -147,8 +154,8 @@ buildFixityMap'
             remainingFixityMap
           ]
 
-memoSet :: (HasTrie a, Eq a) => (Set a -> v) -> Set a -> v
-memoSet f = memo (f . Set.fromAscList) . Set.toAscList
+memoSet :: (Set PackageName -> v) -> Set PackageName -> v
+memoSet f = memo (f . Set.fromAscList . fmap mkPackageName) . fmap unPackageName . Set.toAscList
 
 -- | Merge a list of individual fixity maps, coming from different packages.
 -- Package popularities and the given threshold are used to choose between
@@ -156,11 +163,11 @@ memoSet f = memo (f . Set.fromAscList) . Set.toAscList
 -- strategies when conflicting definitions are encountered for an operator.
 mergeFixityMaps ::
   -- | Map from package name to 30-days download count
-  Map String Int ->
+  Map PackageName Int ->
   -- | Popularity ratio threshold
   Float ->
   -- | List of (package name, package fixity map) to merge
-  [(String, FixityMap)] ->
+  [(PackageName, FixityMap)] ->
   -- | Resulting fixity map
   FixityMap
 mergeFixityMaps popularityMap threshold packageMaps =
@@ -174,7 +181,7 @@ mergeFixityMaps popularityMap threshold packageMaps =
     --   op1 -map-> {definitions1 -map-> originPackages}
     --   op1 -map-> {definitions2 -map-> originPackages}
     -- so we merge the keys (which have the type:
-    -- Map FixityInfo (NonEmpty String))
+    -- Map FixityInfo (NonEmpty PackageName))
     -- using 'Map.unionWith (<>)', to "concatenate" the list of
     -- definitions for this operator, and to also "concatenate" origin
     -- packages if a same definition is found in both maps
@@ -202,7 +209,7 @@ mergeFixityMaps popularityMap threshold packageMaps =
     getScores ::
       -- Map for a given operator associating each of its conflicting
       -- definitions with the packages that define it
-      Map FixityInfo (NonEmpty String) ->
+      Map FixityInfo (NonEmpty PackageName) ->
       -- Map for a given operator associating each of its conflicting
       -- definitions with their score (= sum of the popularity of the
       -- packages that define it)
@@ -212,13 +219,13 @@ mergeFixityMaps popularityMap threshold packageMaps =
         (sum . fmap (fromMaybe 0 . flip Map.lookup popularityMap))
     opFixityMapFrom ::
       -- (packageName, package fixity map)
-      (String, FixityMap) ->
+      (PackageName, FixityMap) ->
       -- Map associating each operator of the package with a
       -- {map for a given operator associating each of its definitions with
       -- the list of packages that define it}
       -- (this list can only be == [packageName] in the context of this
       -- function)
-      Map String (Map FixityInfo (NonEmpty String))
+      Map OpName (Map FixityInfo (NonEmpty PackageName))
     opFixityMapFrom (packageName, opsMap) =
       Map.map
         (flip Map.singleton (packageName :| []))

src/Ormolu/Fixity/Internal.hs

@@ -1,12 +1,19 @@
 {-# LANGUAGE DeriveAnyClass #-}
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE ViewPatterns #-}
 
 module Ormolu.Fixity.Internal
-  ( FixityDirection (..),
+  ( OpName,
+    pattern OpName,
+    unOpName,
+    occOpName,
+    FixityDirection (..),
     FixityInfo (..),
     defaultFixityInfo,
     colonFixityInfo,
@@ -18,10 +25,19 @@ module Ormolu.Fixity.Internal
 where
 
 import Data.Binary (Binary)
+import Data.ByteString.Short (ShortByteString)
+import qualified Data.ByteString.Short as SBS
 import Data.Foldable (asum)
 import Data.Map.Strict (Map)
 import qualified Data.Map.Strict as Map
+import Data.String (IsString (..))
+import Data.Text (Text)
+import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
+import Distribution.Types.PackageName (PackageName)
+import GHC.Data.FastString (fs_sbs)
 import GHC.Generics (Generic)
+import GHC.Types.Name (OccName (occNameFS))
 
 -- | Fixity direction.
 data FixityDirection
@@ -79,8 +95,36 @@ instance Semigroup FixityInfo where
           (Just a, Just b) | a == b -> Just a
           _ -> Nothing
 
+-- | An operator name.
+newtype OpName = MkOpName
+  { -- | Invariant: UTF-8 encoded
+    getOpName :: ShortByteString
+  }
+  deriving newtype (Eq, Ord, Binary)
+
+-- | Convert an 'OpName' to 'Text'.
+unOpName :: OpName -> Text
+unOpName = T.decodeUtf8 . SBS.fromShort . getOpName
+
+pattern OpName :: Text -> OpName
+pattern OpName opName <- (unOpName -> opName)
+  where
+    OpName = MkOpName . SBS.toShort . T.encodeUtf8
+
+{-# COMPLETE OpName #-}
+
+-- | Convert an 'OccName to an 'OpName'.
+occOpName :: OccName -> OpName
+occOpName = MkOpName . fs_sbs . occNameFS
+
+instance Show OpName where
+  show = T.unpack . unOpName
+
+instance IsString OpName where
+  fromString = OpName . T.pack
+
 -- | Map from the operator name to its 'FixityInfo'.
-type FixityMap = Map String FixityInfo
+type FixityMap = Map OpName FixityInfo
 
 -- | A variant of 'FixityMap', represented as a lazy union of several
 -- 'FixityMap's.
@@ -89,16 +133,16 @@ newtype LazyFixityMap = LazyFixityMap [FixityMap]
 
 -- | Lookup a 'FixityInfo' of an operator. This might have drastically
 -- different performance depending on whether this is an "unusual" operator.
-lookupFixity :: String -> LazyFixityMap -> Maybe FixityInfo
+lookupFixity :: OpName -> LazyFixityMap -> Maybe FixityInfo
 lookupFixity op (LazyFixityMap maps) = asum (Map.lookup op <$> maps)
 
 -- | The map of operators declared by each package and the popularity of
 -- each package, if available.
 data HackageInfo
   = HackageInfo
-      (Map String FixityMap)
+      (Map PackageName FixityMap)
       -- ^ Map from package name to a map from operator name to its fixity
-      (Map String Int)
+      (Map PackageName Int)
       -- ^ Map from package name to its 30-days download count from Hackage
   deriving stock (Generic)
   deriving anyclass (Binary)

src/Ormolu/Fixity/Parser.hs

@@ -16,8 +16,9 @@ where
 import qualified Data.Char as Char
 import qualified Data.Map.Strict as Map
 import Data.Text (Text)
+import qualified Data.Text as T
 import Data.Void (Void)
-import Ormolu.Fixity.Internal
+import Ormolu.Fixity
 import Text.Megaparsec
 import Text.Megaparsec.Char
 import qualified Text.Megaparsec.Char.Lexer as L
@@ -39,7 +40,7 @@ parseFixityDeclaration ::
   -- | Expression to parse
   Text ->
   -- | Parse result
-  Either (ParseErrorBundle Text Void) [(String, FixityInfo)]
+  Either (ParseErrorBundle Text Void) [(OpName, FixityInfo)]
 parseFixityDeclaration = runParser (pFixity <* eof) ""
 
 pFixityMap :: Parser FixityMap
@@ -51,7 +52,7 @@ pFixityMap =
 -- | Parse a single fixity declaration, such as
 --
 -- > infixr 4 +++, >>>
-pFixity :: Parser [(String, FixityInfo)]
+pFixity :: Parser [(OpName, FixityInfo)]
 pFixity = do
   fiDirection <- Just <$> pFixityDirection
   hidden hspace1
@@ -72,19 +73,16 @@ pFixityDirection =
     ]
 
 -- | See <https://www.haskell.org/onlinereport/haskell2010/haskellch2.html>
-pOperator :: Parser String
-pOperator = tickedOperator <|> normalOperator
+pOperator :: Parser OpName
+pOperator = OpName <$> (tickedOperator <|> normalOperator)
   where
     tickedOperator = between tick tick haskellIdentifier
     tick = char '`'
-    haskellIdentifier = do
-      x <- letterChar
-      xs <- many (alphaNumChar <|> char '_' <|> char '\'')
-      return (x : xs)
-    normalOperator = some operatorChar
-    operatorChar =
-      satisfy
-        (\x -> (Char.isSymbol x || Char.isPunctuation x) && isNotExcluded x)
-        <?> "operator character"
-      where
-        isNotExcluded x = x /= ',' && x /= '`' && x /= '(' && x /= ')'
+    haskellIdentifier =
+      T.cons
+        <$> letterChar
+        <*> takeWhileP Nothing (\x -> Char.isAlphaNum x || x == '_' || x == '\'')
+    normalOperator =
+      takeWhile1P (Just "operator character") $ \x ->
+        (Char.isSymbol x || Char.isPunctuation x)
+          && (x /= ',' && x /= '`' && x /= '(' && x /= ')')

src/Ormolu/Fixity/Printer.hs

@@ -10,11 +10,12 @@ where
 import qualified Data.Char as Char
 import qualified Data.Map.Strict as Map
 import Data.Text (Text)
+import qualified Data.Text as T
 import qualified Data.Text.Lazy as TL
 import Data.Text.Lazy.Builder (Builder)
 import qualified Data.Text.Lazy.Builder as B
 import qualified Data.Text.Lazy.Builder.Int as B
-import Ormolu.Fixity.Internal
+import Ormolu.Fixity
 
 -- | Print out a textual representation of a 'FixityMap'.
 printFixityMap :: FixityMap -> Text
@@ -26,7 +27,7 @@ printFixityMap =
     . concatMap decompose
     . Map.toList
   where
-    decompose :: (String, FixityInfo) -> [(FixityDirection, Int, String)]
+    decompose :: (OpName, FixityInfo) -> [(FixityDirection, Int, OpName)]
     decompose (operator, FixityInfo {..}) =
       let forDirection dir =
             (dir, fiMinPrecedence, operator)
@@ -36,8 +37,8 @@ printFixityMap =
        in case fiDirection of
             Nothing -> concatMap forDirection [InfixL, InfixR]
             Just dir -> forDirection dir
-    renderOne :: (FixityDirection, Int, String) -> Builder
-    renderOne (fixityDirection, n, operator) =
+    renderOne :: (FixityDirection, Int, OpName) -> Builder
+    renderOne (fixityDirection, n, OpName operator) =
       mconcat
         [ case fixityDirection of
             InfixL -> "infixl"
@@ -47,9 +48,8 @@ printFixityMap =
           B.decimal n,
           " ",
           if isTickedOperator operator
-            then "`" <> B.fromString operator <> "`"
-            else B.fromString operator,
+            then "`" <> B.fromText operator <> "`"
+            else B.fromText operator,
           "\n"
         ]
-    isTickedOperator [] = True
-    isTickedOperator (x : _) = Char.isLetter x
+    isTickedOperator = maybe True (Char.isLetter . fst) . T.uncons

src/Ormolu/Printer/Operators.hs

@@ -16,7 +16,6 @@ import Control.Applicative ((<|>))
 import qualified Data.List.NonEmpty as NE
 import qualified Data.Map.Strict as Map
 import Data.Maybe (fromMaybe)
-import GHC.Types.Name.Occurrence (occNameString)
 import GHC.Types.Name.Reader
 import GHC.Types.SrcLoc
 import Ormolu.Fixity
@@ -44,10 +43,10 @@ data OpTree ty op
 data OpInfo op = OpInfo
   { -- | The actual operator
     opiOp :: op,
-    -- | Its name, if available. We use 'Maybe String' here instead of
-    -- 'String' because the name-fetching function received by
-    -- 'reassociateOpTree' returns a 'Maybe'
-    opiName :: Maybe String,
+    -- | Its name, if available. We use 'Maybe OpName' here instead of 'OpName'
+    -- because the name-fetching function received by 'reassociateOpTree'
+    -- returns a 'Maybe'
+    opiName :: Maybe OpName,
     -- | Information about the fixity direction and precedence level of the
     -- operator
     opiFix :: FixityInfo
@@ -125,7 +124,7 @@ addFixityInfo fixityOverrides fixityMap getOpName (OpBranches exprs ops) =
   where
     toOpInfo o = OpInfo o mName fixityInfo
       where
-        mName = occNameString . rdrNameOcc <$> getOpName o
+        mName = occOpName . rdrNameOcc <$> getOpName o
         fixityInfo =
           fromMaybe
             defaultFixityInfo

src/Ormolu/Utils/Cabal.hs

@@ -6,8 +6,6 @@
 module Ormolu.Utils.Cabal
   ( CabalInfo (..),
     defaultCabalInfo,
-    PackageName,
-    unPackageName,
     Extension (..),
     getCabalInfoForSourceFile,
     findCabalFile,
@@ -41,11 +39,11 @@ import System.IO.Unsafe (unsafePerformIO)
 -- | Cabal information of interest to Ormolu.
 data CabalInfo = CabalInfo
   { -- | Package name
-    ciPackageName :: !(Maybe String),
+    ciPackageName :: !(Maybe PackageName),
     -- | Extension and language settings in the form of 'DynOption's
     ciDynOpts :: ![DynOption],
     -- | Direct dependencies
-    ciDependencies :: !(Set String),
+    ciDependencies :: !(Set PackageName),
     -- | Absolute path to the cabal file, if it was found
     ciCabalFilePath :: !(Maybe FilePath)
   }
@@ -111,7 +109,7 @@ data CachedCabalFile = CachedCabalFile
     genericPackageDescription :: GenericPackageDescription,
     -- | Map from Haskell source file paths (without any extensions) to the
     -- corresponding 'DynOption's and dependencies.
-    extensionsAndDeps :: Map FilePath ([DynOption], [String])
+    extensionsAndDeps :: Map FilePath ([DynOption], [PackageName])
   }
   deriving (Show)
 
@@ -153,10 +151,9 @@ parseCabalInfo cabalFileAsGiven sourceFileAsGiven = liftIO $ do
           <> sourceFileAsGiven
       return ([], [])
   let pdesc = packageDescription genericPackageDescription
-      packageName = (unPackageName . pkgName . package) pdesc
   return
     CabalInfo
-      { ciPackageName = Just packageName,
+      { ciPackageName = Just . pkgName . package $ pdesc,
         ciDynOpts = dynOpts,
         ciDependencies = Set.fromList dependencies,
         ciCabalFilePath = Just cabalFile
@@ -172,7 +169,7 @@ getExtensionAndDepsMap ::
   FilePath ->
   -- | Parsed generic package description
   GenericPackageDescription ->
-  Map FilePath ([DynOption], [String])
+  Map FilePath ([DynOption], [PackageName])
 getExtensionAndDepsMap cabalFile GenericPackageDescription {..} =
   M.unions . concat $
     [ buildMap extractFromLibrary <$> lib ++ sublibs,
@@ -196,7 +193,7 @@ getExtensionAndDepsMap cabalFile GenericPackageDescription {..} =
         prependSrcDirs f
           | null hsSourceDirs = [f]
           | otherwise = (</> f) . getSymbolicPath <$> hsSourceDirs
-        deps = unPackageName . depPkgName <$> targetBuildDepends
+        deps = depPkgName <$> targetBuildDepends
         exts = maybe [] langExt defaultLanguage ++ fmap extToDynOption defaultExtensions
         langExt =
           pure . DynOption . ("-X" <>) . \case

src/Ormolu/Utils/Fixity.hs

@@ -64,6 +64,6 @@ parseFixityDeclarationStr ::
   -- | Input to parse
   String ->
   -- | Parse result
-  Either String [(String, FixityInfo)]
+  Either String [(OpName, FixityInfo)]
 parseFixityDeclarationStr =
   first errorBundlePretty . parseFixityDeclaration . T.pack

tests/Ormolu/CabalInfoSpec.hs

@@ -3,6 +3,7 @@
 module Ormolu.CabalInfoSpec (spec) where
 
 import qualified Data.Set as Set
+import Distribution.Types.PackageName (unPackageName)
 import Ormolu.Config (DynOption (..))
 import Ormolu.Utils.Cabal
 import System.Directory
@@ -32,16 +33,16 @@ spec = do
   describe "parseCabalInfo" $ do
     it "extracts correct package name from ormolu.cabal" $ do
       CabalInfo {..} <- parseCabalInfo "ormolu.cabal" "src/Ormolu/Config.hs"
-      ciPackageName `shouldBe` Just "ormolu"
+      fmap unPackageName ciPackageName `shouldBe` Just "ormolu"
     it "extracts correct dyn opts from ormolu.cabal" $ do
       CabalInfo {..} <- parseCabalInfo "ormolu.cabal" "src/Ormolu/Config.hs"
       ciDynOpts `shouldBe` [DynOption "-XHaskell2010"]
     it "extracts correct dependencies from ormolu.cabal (src/Ormolu/Config.hs)" $ do
       CabalInfo {..} <- parseCabalInfo "ormolu.cabal" "src/Ormolu/Config.hs"
-      ciDependencies `shouldBe` Set.fromList ["Cabal-syntax", "Diff", "MemoTrie", "ansi-terminal", "array", "base", "binary", "bytestring", "containers", "directory", "dlist", "file-embed", "filepath", "ghc-lib-parser", "megaparsec", "mtl", "syb", "text"]
+      Set.map unPackageName ciDependencies `shouldBe` Set.fromList ["Cabal-syntax", "Diff", "MemoTrie", "ansi-terminal", "array", "base", "binary", "bytestring", "containers", "directory", "dlist", "file-embed", "filepath", "ghc-lib-parser", "megaparsec", "mtl", "syb", "text"]
     it "extracts correct dependencies from ormolu.cabal (tests/Ormolu/PrinterSpec.hs)" $ do
       CabalInfo {..} <- parseCabalInfo "ormolu.cabal" "tests/Ormolu/PrinterSpec.hs"
-      ciDependencies `shouldBe` Set.fromList ["QuickCheck", "base", "containers", "directory", "filepath", "ghc-lib-parser", "hspec", "hspec-megaparsec", "ormolu", "path", "path-io", "temporary", "text"]
+      Set.map unPackageName ciDependencies `shouldBe` Set.fromList ["Cabal-syntax", "QuickCheck", "base", "containers", "directory", "filepath", "ghc-lib-parser", "hspec", "hspec-megaparsec", "ormolu", "path", "path-io", "temporary", "text"]
 
     it "handles `hs-source-dirs: .`" $ do
       CabalInfo {..} <- parseTestCabalInfo "Foo.hs"

tests/Ormolu/Fixity/PrinterSpec.hs

@@ -4,6 +4,7 @@ module Ormolu.Fixity.PrinterSpec (spec) where
 
 import qualified Data.Char as Char
 import qualified Data.Map.Strict as Map
+import qualified Data.Text as T
 import Ormolu.Fixity
 import Ormolu.Fixity.Parser
 import Ormolu.Fixity.Printer
@@ -20,7 +21,8 @@ instance Arbitrary FixityMapWrapper where
       <$> listOf ((,) <$> genOperator <*> genFixityInfo)
     where
       scaleDown = scale (`div` 4)
-      genOperator = oneof [genNormalOperator, genIdentifier]
+      genOperator =
+        OpName . T.pack <$> oneof [genNormalOperator, genIdentifier]
       genNormalOperator =
         listOf1 (scaleDown arbitrary `suchThat` isOperatorConstituent)
       isOperatorConstituent x =

tests/Ormolu/HackageInfoSpec.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE TupleSections #-}
 
 module Ormolu.HackageInfoSpec (spec) where
@@ -5,6 +6,7 @@ module Ormolu.HackageInfoSpec (spec) where
 import qualified Data.Map.Strict as Map
 import Data.Maybe (mapMaybe)
 import qualified Data.Set as Set
+import Distribution.Types.PackageName (PackageName)
 import Ormolu.Fixity
 import Test.Hspec
 
@@ -13,12 +15,12 @@ import Test.Hspec
 -- operators.
 checkFixityMap ::
   -- | List of dependencies
-  [String] ->
+  [PackageName] ->
   -- | Threshold to choose the conflict resolution strategy
   Float ->
   -- | Associative list representing a subset of the resulting fixity map
   -- that should be checked.
-  [(String, FixityInfo)] ->
+  [(OpName, FixityInfo)] ->
   Expectation
 checkFixityMap
   dependencies
@@ -43,20 +45,20 @@ checkFixityMap
 checkFixityMap' ::
   -- | Associative list for packageToOps:
   -- package name -map-> (operator -map-> fixity)
-  [(String, [(String, FixityInfo)])] ->
+  [(PackageName, [(OpName, FixityInfo)])] ->
   -- | Associative list for packageToPopularity:
   -- package name -map-> download count
-  [(String, Int)] ->
+  [(PackageName, Int)] ->
   -- | List of packages that should have a higher priority than
   -- unspecified packages (boot packages)
-  [String] ->
+  [PackageName] ->
   -- | List of dependencies
-  [String] ->
+  [PackageName] ->
   -- | Threshold to choose the conflict resolution strategy
   Float ->
   -- | Associative list representing a subset of the resulting fixity map
   -- that should be checked.
-  [(String, FixityInfo)] ->
+  [(OpName, FixityInfo)] ->
   Expectation
 checkFixityMap'
   lPackageToOps

tests/Ormolu/OpTreeSpec.hs

@@ -1,7 +1,11 @@
+{-# LANGUAGE OverloadedStrings #-}
+
 module Ormolu.OpTreeSpec (spec) where
 
 import qualified Data.Map.Strict as Map
 import Data.Maybe (fromJust)
+import Data.Text (Text)
+import qualified Data.Text as T
 import GHC.Types.Name (mkOccName, varName)
 import GHC.Types.Name.Reader (mkRdrUnqual)
 import Ormolu.Fixity
@@ -9,17 +13,17 @@ import Ormolu.Fixity.Internal (LazyFixityMap (..))
 import Ormolu.Printer.Operators
 import Test.Hspec
 
-n :: String -> OpTree String String
+n :: Text -> OpTree Text OpName
 n = OpNode
 
 -- | Check that the input tree is actually reassociated as expected.
 checkReassociate ::
   -- | Fixity map used for the reassociation
-  [(String, FixityInfo)] ->
+  [(OpName, FixityInfo)] ->
   -- | Input tree
-  OpTree String String ->
+  OpTree Text OpName ->
   -- | Expected output tree
-  OpTree String String ->
+  OpTree Text OpName ->
   Expectation
 checkReassociate lFixities inputTree expectedOutputTree =
   removeOpInfo actualOutputTree `shouldBe` expectedOutputTree
@@ -29,10 +33,10 @@ checkReassociate lFixities inputTree expectedOutputTree =
       OpBranches (removeOpInfo <$> exprs) (opiOp <$> ops)
     actualOutputTree = reassociateOpTree convertName Map.empty fixityMap inputTree
     fixityMap = LazyFixityMap [Map.fromList lFixities]
-    convertName = Just . mkRdrUnqual . mkOccName varName
+    convertName = Just . mkRdrUnqual . mkOccName varName . T.unpack . unOpName
 
 -- | Associative list of fixities for operators from "base"
-baseFixities :: [(String, FixityInfo)]
+baseFixities :: [(OpName, FixityInfo)]
 baseFixities = Map.toList . fromJust $ Map.lookup "base" packageToOps
 
 spec :: Spec

tests/Ormolu/PrinterSpec.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE TemplateHaskell #-}
 
 module Ormolu.PrinterSpec (spec) where