reproduce signal delivery ordering misunderstaning

sdk/test/IntegrationSpec.hs

@@ -1482,6 +1482,35 @@ needsClient = do
                 2
             lift $ C.waitWorkflowResult wfH `shouldReturn` 25
 
+      it "processes signals in order of delivery" $ \TestEnv {..} -> do
+        let conf = provideCallStack $ configure () (discoverDefinitions @() $$(discoverInstances) $$(discoverInstances)) baseConf
+        withWorker conf $ do
+          let opts =
+                (C.startWorkflowOptions taskQueue)
+                  { C.workflowIdReusePolicy = Just W.WorkflowIdReusePolicyAllowDuplicate
+                  , C.timeouts =
+                      C.TimeoutOptions
+                        { C.runTimeout = Just $ seconds 4
+                        , C.executionTimeout = Nothing
+                        , C.taskTimeout = Nothing
+                        }
+                  }
+          useClient $ do
+            liftIO $ putStrLn "signalWithStart call"
+            wfH <-
+              C.signalWithStart
+                SignalEnqueuesItemWorkflow
+                "signalWithStartWithQueue"
+                opts
+                signalWithArgs
+                1
+
+            -- liftIO $ threadDelay 1_000
+
+            C.signal wfH signalWithArgs C.defaultSignalOptions 2
+            lift $ C.waitWorkflowResult wfH `shouldReturn` [1, 2]
+
+
   --     specify "works as intended and returns correct runId" pending
   describe "RetryPolicy" $ do
     specify "is used for retryable failures" $ \TestEnv {..} -> do

sdk/test/IntegrationSpec/Signals.hs

@@ -53,3 +53,18 @@ signalWithArgsWorkflow init = provideCallStack do
 
 
 registerWorkflow 'signalWithArgsWorkflow
+
+
+signalEnqueuesItemWorkflow :: Workflow [Int]
+signalEnqueuesItemWorkflow = provideCallStack do
+  var <- newStateVar []
+  setSignalHandler signalWithArgs $ \i -> do
+    $(logDebug) "updating value and unblocking workflow"
+    readStateVar var >>= \s -> writeStateVar var (s <> [i])
+
+  sleep (seconds 2)
+
+  waitCondition $ (not . null) <$> readStateVar var
+  readStateVar var
+
+registerWorkflow 'signalEnqueuesItemWorkflow