Prevent tests from running concurrently

cardano-testnet/src/Testnet/Property/Utils.hs

@@ -27,7 +27,8 @@ import           Cardano.Chain.Genesis (GenesisHash (unGenesisHash), readGenesis
 import qualified Cardano.Crypto.Hash.Blake2b as Crypto
 import qualified Cardano.Crypto.Hash.Class as Crypto
 
-import qualified Control.Exception.Lifted as E
+import qualified Control.Concurrent.QSem as IO
+import qualified Control.Exception.Lifted as CE
 import           Control.Exception.Safe (MonadCatch)
 import           Control.Monad
 import           Control.Monad.Trans.Resource
@@ -55,11 +56,14 @@ disableRetries = IO.unsafePerformIO $ do
   return $ mValue == Just "1"
 {-# NOINLINE disableRetries #-}
 
-sem :: 
+sem :: IO.QSem
+sem = IO.unsafePerformIO $ IO.newQSem 1
+{-# NOINLINE sem #-}
 
 -- TODO: Document what an Integration is
 integration :: HasCallStack => H.Integration () -> H.Property
-integration f = GHC.withFrozenCallStack $ H.withTests 1 $ H.propertyOnce $ E.bracket_ (pure ()) (pure ()) f
+integration f = GHC.withFrozenCallStack $ H.withTests 1 $ H.propertyOnce $
+  CE.bracket_ (liftIO $ IO.waitQSem sem) (liftIO $ IO.signalQSem sem) f
 
 -- | The 'FilePath' in '(FilePath -> H.Integration ())' is the work space directory.
 -- This is created (and returned) via 'H.workspace'.