Fix chat history paging around tool updates (#1247)

* Fix projected timeline paging * Avoid full timeline fetches for plain pages
2026-05-31 05:38:29 +00:00
parent 0e3eb9cf75
commit 3d96ea6354
18 changed files with 890 additions and 256 deletions
@@ -547,6 +547,153 @@ describe("processTimelineResponse", () => {
    });
  });

+  it("hydrates a fetched in-progress tool call as one item and streams the next update on top", () => {
+    const fetched = processTimelineResponse({
+      ...baseTimelineInput,
+      isInitializing: true,
+      hasActiveInitDeferred: true,
+      initRequestDirection: "tail",
+      payload: {
+        ...baseTimelineInput.payload,
+        direction: "tail",
+        epoch: "epoch-1",
+        startCursor: { seq: 10 },
+        endCursor: { seq: 250 },
+        entries: [
+          {
+            ...makeToolCallTimelineEntry(10, "call-1", "running", {
+              type: "read",
+              filePath: "/tmp/example.ts",
+            }),
+            seqEnd: 250,
+            sourceSeqRanges: [
+              { startSeq: 10, endSeq: 10 },
+              { startSeq: 250, endSeq: 250 },
+            ],
+            collapsed: ["tool_lifecycle"],
+          },
+        ],
+      },
+    });
+
+    expect(getAgentToolCalls(fetched.tail)).toHaveLength(1);
+    expect(fetched.cursor).toEqual({ epoch: "epoch-1", startSeq: 10, endSeq: 250 });
+
+    const streamed = processAgentStreamEvent({
+      ...baseStreamInput,
+      currentTail: fetched.tail,
+      currentHead: fetched.head,
+      currentCursor: fetched.cursor ?? undefined,
+      seq: 251,
+      epoch: "epoch-1",
+      event: {
+        type: "timeline",
+        provider: "claude",
+        item: {
+          type: "tool_call",
+          callId: "call-1",
+          name: "Read",
+          status: "completed",
+          detail: {
+            type: "read",
+            filePath: "/tmp/example.ts",
+          },
+          error: null,
+        },
+      } as AgentStreamEventPayload,
+    });
+
+    const tools = getAgentToolCalls(streamed.tail);
+    expect(tools).toHaveLength(1);
+    expect(tools[0]?.payload.data.status).toBe("completed");
+    expect(streamed.cursor).toEqual({ epoch: "epoch-1", startSeq: 10, endSeq: 251 });
+  });
+
+  it("accepts an after-page projected tool update whose item started before the cursor", () => {
+    const existingCursor: TimelineCursor = {
+      epoch: "epoch-1",
+      startSeq: 10,
+      endSeq: 249,
+    };
+    const runningTool = hydrateStreamState(
+      [
+        {
+          event: makeToolCallTimelineEvent("call-1"),
+          timestamp: new Date(1010),
+        },
+      ],
+      { source: "canonical" },
+    );
+
+    const result = processTimelineResponse({
+      ...baseTimelineInput,
+      currentTail: runningTool,
+      currentCursor: existingCursor,
+      payload: {
+        ...baseTimelineInput.payload,
+        direction: "after",
+        epoch: "epoch-1",
+        startCursor: { seq: 250 },
+        endCursor: { seq: 250 },
+        entries: [
+          {
+            ...makeToolCallTimelineEntry(10, "call-1", "completed", {
+              type: "read",
+              filePath: "/tmp/example.ts",
+            }),
+            seqEnd: 250,
+            sourceSeqRanges: [
+              { startSeq: 10, endSeq: 10 },
+              { startSeq: 250, endSeq: 250 },
+            ],
+            collapsed: ["tool_lifecycle"],
+          },
+        ],
+      },
+    });
+
+    const catchUp = result.sideEffects.find((effect) => effect.type === "catch_up");
+    const tools = getAgentToolCalls(result.tail);
+    expect(catchUp).toBeUndefined();
+    expect(tools).toHaveLength(1);
+    expect(tools[0]?.payload.data.status).toBe("completed");
+    expect(result.cursor).toEqual({ epoch: "epoch-1", startSeq: 10, endSeq: 250 });
+  });
+
+  it("replaces an active assistant head when after-page returns a full projected assistant item", () => {
+    const existingCursor: TimelineCursor = {
+      epoch: "epoch-1",
+      startSeq: 1,
+      endSeq: 3,
+    };
+    const currentHead = [makeAssistantItem("ABC")];
+
+    const result = processTimelineResponse({
+      ...baseTimelineInput,
+      currentHead,
+      currentCursor: existingCursor,
+      payload: {
+        ...baseTimelineInput.payload,
+        direction: "after",
+        epoch: "epoch-1",
+        startCursor: { seq: 4 },
+        endCursor: { seq: 5 },
+        entries: [
+          {
+            ...makeTimelineEntry(1, "ABCDE"),
+            seqEnd: 5,
+            sourceSeqRanges: [{ startSeq: 1, endSeq: 5 }],
+            collapsed: ["assistant_merge"],
+          },
+        ],
+      },
+    });
+
+    expect(getAssistantTexts(result.tail)).toEqual([]);
+    expect(getAssistantTexts(result.head)).toEqual(["ABCDE"]);
+    expect(result.cursor).toEqual({ epoch: "epoch-1", startSeq: 1, endSeq: 5 });
+  });
+
  it("detects gap and emits catch-up side effect", () => {
    const existingCursor: TimelineCursor = {
      epoch: "epoch-1",