check + expand: Allow passing in multiple files

Language/Haskell/GhcMod/Check.hs

@@ -16,9 +16,14 @@ import Prelude
 --   Warnings and errors are returned.
 checkSyntax :: Options
             -> Cradle
-            -> FilePath  -- ^ A target file
+            -> [FilePath]  -- ^ The target files
             -> IO String
-checkSyntax opt cradle file = unlines <$> withGHC file (check opt cradle file)
+checkSyntax _   _      []    = error "ghc-mod: checkSyntax: No files given"
+checkSyntax opt cradle files = unlines <$> withGHC sessionName (check opt cradle files)
+  where
+    sessionName = case files of
+      [file] -> file
+      _      -> "MultipleFiles"
 
 ----------------------------------------------------------------
 
@@ -26,13 +31,14 @@ checkSyntax opt cradle file = unlines <$> withGHC file (check opt cradle file)
 --   Warnings and errors are returned.
 check :: Options
       -> Cradle
-      -> FilePath  -- ^ A target file
+      -> [FilePath]  -- ^ The target files
       -> Ghc [String]
-check opt cradle fileName = checkIt `gcatch` handleErrMsg ls
+check _   _      []        = error "ghc-mod: check: No files given"
+check opt cradle fileNames = checkIt `gcatch` handleErrMsg ls
   where
     checkIt = do
         readLog <- initializeFlagsWithCradle opt cradle options True
-        setTargetFile fileName
+        setTargetFiles fileNames
         checkSlowAndSet
         void $ load LoadAllTargets
         liftIO readLog

Language/Haskell/GhcMod/Debug.hs

@@ -36,7 +36,7 @@ debug opt cradle ver fileName = do
             return (ghcOpts opt, [], [])
     [fast] <- do
         void $ initializeFlagsWithCradle opt cradle gopts True
-        setTargetFile fileName
+        setTargetFiles [fileName]
         pure . canCheckFast <$> depanal [] False
     return [
         "GHC version:         " ++ ver

Language/Haskell/GhcMod/GHCApi.hs

@@ -5,7 +5,7 @@ module Language.Haskell.GhcMod.GHCApi (
   , withGHCDummyFile
   , initializeFlags
   , initializeFlagsWithCradle
-  , setTargetFile
+  , setTargetFiles
   , getDynamicFlags
   , setSlowDynFlags
   , checkSlowAndSet
@@ -154,11 +154,12 @@ modifyFlagsWithOpts dflags cmdOpts =
 
 ----------------------------------------------------------------
 
--- | Set the file that GHC will load / compile
-setTargetFile :: (GhcMonad m) => String -> m ()
-setTargetFile file = do
-    target <- guessTarget file Nothing
-    setTargets [target]
+-- | Set the files that GHC will load / compile
+setTargetFiles :: (GhcMonad m) => [String] -> m ()
+setTargetFiles [] = error "ghc-mod: setTargetFiles: No target files given"
+setTargetFiles files = do
+    targets <- forM files $ \file -> guessTarget file Nothing
+    setTargets targets
 
 ----------------------------------------------------------------
 

Language/Haskell/GhcMod/Info.hs

@@ -148,7 +148,7 @@ inModuleContext cmd opt cradle file modstr action errmsg =
     valid = do
         void $ initializeFlagsWithCradle opt cradle ["-w:"] False
         when (cmd == Info) setSlowDynFlags
-        setTargetFile file
+        setTargetFiles [file]
         checkSlowAndSet
         void $ load LoadAllTargets
         doif setContextFromTarget action

Language/Haskell/GhcMod/Internal.hs

@@ -5,7 +5,7 @@ module Language.Haskell.GhcMod.Internal (
     LogReader
   , GHCOption
   , initializeFlagsWithCradle
-  , setTargetFile
+  , setTargetFiles
   , checkSlowAndSet
   , getDynamicFlags
   ) where