tests: block on tcp server creation (#99)

Co-authored-by: Evgeny Poberezkin <2769109+epoberezkin@users.noreply.github.com>

tests/SMPClient.hs

@@ -9,13 +9,15 @@ import Control.Monad.IO.Unlift
 import Crypto.Random
 import Network.Socket
 import Simplex.Messaging.Protocol
-import Simplex.Messaging.Server
+import Simplex.Messaging.Server (runSMPServerBlocking)
 import Simplex.Messaging.Server.Env.STM
 import Simplex.Messaging.Transport
+import System.Timeout (timeout)
 import Test.Hspec
 import UnliftIO.Concurrent
 import qualified UnliftIO.Exception as E
 import UnliftIO.IO
+import UnliftIO.STM (atomically, newEmptyTMVarIO, takeTMVar)
 
 testHost :: HostName
 testHost = "localhost"
@@ -25,7 +27,6 @@ testPort = "5000"
 
 testSMPClient :: MonadUnliftIO m => (Handle -> m a) -> m a
 testSMPClient client = do
-  threadDelay 250_000 -- TODO hack: thread delay for SMP server to start
   runTCPClient testHost testPort $ \h -> do
     line <- liftIO $ getLn h
     if line == "Welcome to SMP v0.2.0"
@@ -42,10 +43,12 @@ cfg =
     }
 
 withSmpServerThreadOn :: (MonadUnliftIO m, MonadRandom m) => ServiceName -> (ThreadId -> m a) -> m a
-withSmpServerThreadOn port =
+withSmpServerThreadOn port f = do
+  started <- newEmptyTMVarIO
   E.bracket
-    (forkIOWithUnmask ($ runSMPServer cfg {tcpPort = port}))
+    (forkIOWithUnmask ($ runSMPServerBlocking started cfg {tcpPort = port}))
     (liftIO . killThread)
+    \x -> liftIO (5_000_000 `timeout` atomically (takeTMVar started)) >> f x
 
 withSmpServerOn :: (MonadUnliftIO m, MonadRandom m) => ServiceName -> m a -> m a
 withSmpServerOn port = withSmpServerThreadOn port . const