Exit the server and its listener properly

diff --git a/src/Language/Haskell/LSP/Test.hs b/src/Language/Haskell/LSP/Test.hs
index c4b90fb944489828f718d173db11bb902bc1e822..7e87fcb3b915756b7057a71d0b511eb626b2b588 100644 (file)
--- a/src/Language/Haskell/LSP/Test.hs
+++ b/src/Language/Haskell/LSP/Test.hs
@@ -37,8 +37,9 @@ module Language.Haskell.LSP.Test
   , module Language.Haskell.LSP.Test.Parsing
   -- * Utilities
   -- | Quick helper functions for common tasks.
-  -- ** Initialization
+  -- ** Lifecycle
   , initializeResponse
+  , exitServer
   -- ** Documents
   , openDoc
   , openDoc'
@@ -149,7 +150,7 @@ runSessionWithConfig config serverExe caps rootDir session = do
                                           (Just TraceOff)
                                           Nothing
   withServer serverExe (logStdErr config) $ \serverIn serverOut _ ->
-    runSessionWithHandles serverIn serverOut (\h c -> listenServer h c) config caps rootDir $ do
+    runSessionWithHandles serverIn serverOut listenServer config caps rootDir exitServer $ do
       -- Wrap the session around initialize and shutdown calls
       initRspMsg <- request Initialize initializeParams :: Session InitializeResponse
 
@@ -157,7 +158,6 @@ runSessionWithConfig config serverExe caps rootDir session = do
 
       initRspVar <- initRsp <$> ask
       liftIO $ putMVar initRspVar initRspMsg
-
       sendNotification Initialized InitializedParams
 
       case lspConfig config of
@@ -168,11 +168,8 @@ runSessionWithConfig config serverExe caps rootDir session = do
       result <- session
       return result
   where
-  -- | Listens to the server output, makes sure it matches the record and
-  -- signals any semaphores
-  -- Note that on Windows, we cannot kill a thread stuck in getNextMessage.
-  -- So we have to wait for the exit notification to kill the process first
-  -- and then getNextMessage will fail.
+  -- | Listens to the server output until the shutdown ack,
+  -- makes sure it matches the record and signals any semaphores
   listenServer :: Handle -> SessionContext -> IO ()
   listenServer serverOut context = do
     msgBytes <- getNextMessage serverOut
@@ -182,7 +179,9 @@ runSessionWithConfig config serverExe caps rootDir session = do
     let msg = decodeFromServerMsg reqMap msgBytes
     writeChan (messageChan context) (ServerMessage msg)
 
-    listenServer serverOut context
+    case msg of
+      (RspShutdown _) -> return ()
+      _               -> listenServer serverOut context
 
 -- | The current text contents of a document.
 documentContents :: TextDocumentIdentifier -> Session T.Text
@@ -576,3 +575,7 @@ getCodeLenses tId = do
     rsp <- request TextDocumentCodeLens (CodeLensParams tId) :: Session CodeLensResponse
     case getResponseResult rsp of
         List res -> pure res
+        
+-- | Exit the server after request its shutdown
+exitServer :: Session()
+exitServer = request_ Shutdown (Nothing :: Maybe Value) >> sendNotification Exit ExitParams

diff --git a/src/Language/Haskell/LSP/Test/Replay.hs b/src/Language/Haskell/LSP/Test/Replay.hs
index b2d54a39de2b0c561cfad93ccffed9e29d814d73..7d10763aab553ba19c0239df863fdafae057d9c3 100644 (file)
--- a/src/Language/Haskell/LSP/Test/Replay.hs
+++ b/src/Language/Haskell/LSP/Test/Replay.hs
@@ -65,6 +65,7 @@ replaySession serverExe sessionDir = do
                             def
                             fullCaps
                             sessionDir
+                            exitServer
                             (sendMessages clientMsgs reqSema rspSema)
     takeMVar passSema
     killThread sessionThread

diff --git a/src/Language/Haskell/LSP/Test/Session.hs b/src/Language/Haskell/LSP/Test/Session.hs
index ae8ba1e0fbb15917697bd8e2f3589ebcf59a0862..1777f15f2750a913e812df81c7a42d7c6156fee1 100644 (file)
--- a/src/Language/Haskell/LSP/Test/Session.hs
+++ b/src/Language/Haskell/LSP/Test/Session.hs
@@ -48,7 +48,6 @@ import Data.Conduit as Conduit
 import Data.Conduit.Parser as Parser
 import Data.Default
 import Data.Foldable
-import Data.IORef
 import Data.List
 import qualified Data.Map as Map
 import qualified Data.Text as T
@@ -191,12 +190,10 @@ runSessionWithHandles :: Handle -- ^ Server in
                       -> SessionConfig
                       -> ClientCapabilities
                       -> FilePath -- ^ Root directory
+                      -> Session () -- ^ To exit Server
                       -> Session a
                       -> IO a
-runSessionWithHandles serverIn serverOut serverHandler config caps rootDir session = do
-  -- We use this IORef to make exception non-fatal when the server is supposed to shutdown.
-
-  exitOk <- newIORef False
+runSessionWithHandles serverIn serverOut serverHandler config caps rootDir exitServer session = do
   
   absRootDir <- canonicalizePath rootDir
 
@@ -215,15 +212,13 @@ runSessionWithHandles serverIn serverOut serverHandler config caps rootDir sessi
 
   let context = SessionContext serverIn absRootDir messageChan reqMap initRsp config caps
       initState = SessionState (IdInt 0) mempty mempty 0 False Nothing
-      errorHandler ex = do x <- readIORef exitOk 
-                           unless x $ throwTo mainThreadId (ex :: SessionException)
-      launchServerHandler = forkIO $ catch (serverHandler serverOut context) errorHandler
-  (result, _) <- bracket
-                   launchServerHandler
-                   (\tid -> do runSession context initState sendExitMessage
-                               killThread tid
-                               atomicWriteIORef exitOk True)
-                   (const $ runSession context initState session)
+      runSession' = runSession context initState
+      
+      errorHandler = throwTo mainThreadId :: SessionException -> IO()
+      serverLauncher = forkIO $ catch (serverHandler serverOut context) errorHandler
+      serverFinalizer tid = runSession' exitServer >> killThread tid
+      
+  (result, _) <- bracket serverLauncher serverFinalizer (const $ runSession' session)
   return result
 
 updateStateC :: ConduitM FromServerMessage FromServerMessage (StateT SessionState (ReaderT SessionContext IO)) ()
@@ -310,9 +305,6 @@ sendMessage msg = do
   logMsg LogClient msg
   liftIO $ B.hPut h (addHeader $ encode msg)
 
-sendExitMessage :: (MonadIO m, HasReader SessionContext m) => m ()
-sendExitMessage = sendMessage (NotificationMessage "2.0" Exit ExitParams)
-
 -- | Execute a block f that will throw a 'Timeout' exception
 -- after duration seconds. This will override the global timeout
 -- for waiting for messages to arrive defined in 'SessionConfig'.