+import Data.Aeson
+import qualified Data.ByteString.Lazy.Char8 as B
+import Data.Conduit.Parser
+import Data.Maybe
+import qualified Data.Text as T
+import Data.Typeable
+import Language.Haskell.LSP.Messages
+import Language.Haskell.LSP.Types as LSP hiding (error)
+import Language.Haskell.LSP.Test.Messages
+import Language.Haskell.LSP.Test.Session
+import System.Console.ANSI
+
+satisfy :: (FromServerMessage -> Bool) -> Session FromServerMessage
+satisfy pred = do
+
+ skipTimeout <- overridingTimeout <$> get
+ timeoutId <- curTimeoutId <$> get
+ unless skipTimeout $ do
+ chan <- asks messageChan
+ timeout <- asks (messageTimeout . config)
+ void $ liftIO $ forkIO $ do
+ threadDelay (timeout * 1000000)
+ writeChan chan (TimeoutMessage timeoutId)
+
+ x <- await
+
+ unless skipTimeout $
+ modify $ \s -> s { curTimeoutId = timeoutId + 1 }
+
+ modify $ \s -> s { lastReceivedMessage = Just x }
+
+ if pred x
+ then do
+ liftIO $ do
+ setSGR [SetColor Foreground Vivid Magenta]
+ putStrLn $ "<-- " ++ B.unpack (encodeMsg x)
+ setSGR [Reset]
+ return x
+ else empty