From d895e49145222eb02eb34cd7de93c5212884f5cc Mon Sep 17 00:00:00 2001
From: morluto <76467478+morluto@users.noreply.github.com>
Date: Wed, 22 Jul 2026 20:42:57 +0000
Subject: [PATCH] fix(process): preserve replay event causality

---
 src/application/LoopbackReplayRecorder.ts | 10 +++++++---
 tests/processCapture.test.ts              |  7 +++++++
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/src/application/LoopbackReplayRecorder.ts b/src/application/LoopbackReplayRecorder.ts
index d676ab434..74736cba9 100644
--- a/src/application/LoopbackReplayRecorder.ts
+++ b/src/application/LoopbackReplayRecorder.ts
@@ -70,10 +70,12 @@ export class ReplayRecorder {
   ): ReplayMachineDecision {
     if (this.machine === undefined)
       throw new Error("replay machine is not configured");
-    const decision = this.machine.dispatch(event);
+    return this.machine.dispatch(event);
+  }
+
+  recordTransition(decision: ReplayMachineDecision): void {
     if (decision.transition !== null)
       this.recordEvent("replay_transitions", decision.transition.sequence);
-    return decision;
   }
 
   record(event: Omit<ProtocolEvent, "sequence">): void {
@@ -117,12 +119,14 @@ export const recordMachineEvent = (
   recorder: ReplayRecorder,
   event: Omit<ProtocolEvent, "sequence" | "outcome">,
   decision: ReplayMachineDecision,
-): void =>
+): void => {
   recorder.record({
     ...event,
     data: recorder.machine?.redact(event.data) ?? event.data,
     outcome: decision.outcome,
   });
+  recorder.recordTransition(decision);
+};
 
 export const waitForReplayDelay = (durationMs: number): Promise<void> =>
   new Promise((resolveDelay) => setTimeout(resolveDelay, durationMs));
diff --git a/tests/processCapture.test.ts b/tests/processCapture.test.ts
index f67eaa5de..f3f2b2db2 100644
--- a/tests/processCapture.test.ts
+++ b/tests/processCapture.test.ts
@@ -1400,6 +1400,13 @@ describe("process capture adapter", () => {
           ({ collection }) => collection === "replay_transitions",
         ),
       ).toHaveLength(capture.value.replay_transitions.length);
+      for (const [index, entry] of (
+        capture.value.event_journal ?? []
+      ).entries())
+        if (entry.collection === "replay_transitions")
+          expect(capture.value.event_journal?.[index - 1]?.collection).toBe(
+            "protocol_events",
+          );
     } finally {
       await rm(root, { recursive: true, force: true });
     }