From fb5ffafa51c27d78101e0ec059f40cf4d6c41489 Mon Sep 17 00:00:00 2001
From: "paseo-bot[bot]" <266920839+paseo-bot[bot]@users.noreply.github.com>
Date: Fri, 23 Oct 2026 19:44:42 +0200
Subject: [PATCH] test(plugin): cover kind-qualified ACP history identities

---
 packages/plugin/src/server/acp.test.ts | 50 ++++++++++++++++++++++++--
 1 file changed, 48 insertions(+), 2 deletions(-)

diff --git a/packages/plugin/src/server/acp.test.ts b/packages/plugin/src/server/acp.test.ts
index c4d327e6aa..1d99c73a75 100644
--- a/packages/plugin/src/server/acp.test.ts
+++ b/packages/plugin/src/server/acp.test.ts
@@ -1611,8 +1611,12 @@ describe("ACP session history replay", () => {
     );
     try {
       expect(timelineProjection(events)).toEqual([
-        { type: "user_message", id: "user-1", text: "What is the " },
-        { type: "user_message", id: "user-1", text: "What is the temperature?" },
+        { type: "user_message", id: '["user_message_chunk","user-1"]', text: "What is the " },
+        {
+          type: "user_message",
+          id: '["user_message_chunk","user-1"]',
+          text: "What is the temperature?",
+        },
         { type: "reasoning", id: "agent_thought_chunk:1", text: "Checking the sensor" },
         { type: "tool_call", id: "tool-1", status: "running" },
         { type: "tool_call", id: "tool-1", status: "completed" },
@@ -1626,6 +1630,48 @@ describe("ACP session history replay", () => {
     }
   });
 
+  it("keeps replayed user, reasoning and reply chunks separate when their native IDs match", async () => {
+    const { connection, events } = await openReplaySession(
+      [
+        userChunk("What is the ", "shared-id"),
+        userChunk("temperature?", "shared-id"),
+        textChunk("Checking ", "agent_thought_chunk", "shared-id"),
+        textChunk("the sensor", "agent_thought_chunk", "shared-id"),
+        textChunk("It is ", "agent_message_chunk", "shared-id"),
+        textChunk("25°C", "agent_message_chunk", "shared-id"),
+      ],
+      "replay",
+    );
+    try {
+      const items = new Map(
+        events.flatMap((event) =>
+          event.type === "timeline.item" ? [[event.item.id, event.item] as const] : [],
+        ),
+      );
+      expect([...items.values()]).toEqual([
+        {
+          type: "user_message",
+          id: '["user_message_chunk","shared-id"]',
+          messageId: "shared-id",
+          text: "What is the temperature?",
+        },
+        {
+          type: "reasoning",
+          id: '["agent_thought_chunk","shared-id"]',
+          text: "Checking the sensor",
+        },
+        {
+          type: "assistant_message",
+          id: '["agent_message_chunk","shared-id"]',
+          messageId: "shared-id",
+          text: "It is 25°C",
+        },
+      ]);
+    } finally {
+      await connection.close();
+    }
+  });
+
   it("continues anonymous user chunks into one message and starts a new one after an agent reply", async () => {
     const { connection, events } = await openReplaySession(
       [