From fde2c2fa5bb42b6682fd4e828893dda13e0b3915 Mon Sep 17 00:00:00 2001
From: Steve Gibson <steve@clockwokrlabs.io>
Date: Tue, 12 Aug 2025 17:27:06 -0400
Subject: [PATCH] Raise unhandled error on arg mismatch

---
 src/SpacetimeDBClient.cs | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/SpacetimeDBClient.cs b/src/SpacetimeDBClient.cs
index c19f05b2e..e72604cc3 100644
--- a/src/SpacetimeDBClient.cs
+++ b/src/SpacetimeDBClient.cs
@@ -910,6 +910,18 @@ private void ApplyMessage(ParsedMessage parsed)
                         {
                             var legacyEventContext = ToEventContext(new Event<Reducer>.UnknownTransaction());
                             ApplyUpdate(legacyEventContext, dbOps);
+
+                            if (transactionUpdate.Status is UpdateStatus.Failed(string err))
+                            {
+                                var fiReducers = GetType().GetField("Reducers", System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance);
+                                var reducers = fiReducers.GetValue(this);
+                                var fiEvent = reducers.GetType().GetField("InternalOnUnhandledReducerError", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
+                                var unhandledErrorEvent = fiEvent.GetValue(reducers) as Delegate;
+                                if (unhandledErrorEvent != null)
+                                {
+                                    unhandledErrorEvent.DynamicInvoke(null, new Exception(err));
+                                }
+                            }
                         }
                         break;
                     }