Make flag-decision tests fail fast and assert the outbound metric

test/BusSpec.hs

@@ -21,6 +21,7 @@ import HomeAssistant.Runtime.Metrics (registerAppMetrics)
 import Katip (Namespace (Namespace), runKatipContextT, Severity (..))
 import qualified System.Metrics as Metrics
 import System.IO.Temp (withTempDirectory)
+import System.Timeout (timeout)
 import Test.Hspec
 
 spec :: Spec
@@ -50,9 +51,10 @@ spec = describe "Bus" $ do
           svc = Service "light" "turn_on" Nothing [EntityId "light.test"]
       runKatipContextT (busLogEnv bus) () (Namespace ["test"]) $
         channelHassEval bus (CallService req svc)
-      (_, svc') <- atomically $ readTChan (busOutbound bus)
-      svc' `shouldBe` svc
-
+      result <- timeout 1000000 $ atomically $ readTChan (busOutbound bus)
+      case result of
+        Nothing -> expectationFailure "expected a write to the outbound channel"
+        Just (_, svc') -> svc' `shouldBe` svc
 
   it "generates unique sequential call ids" $ do
     gen <- mkCallIdGen 0