fix(record): record switch_tab and keep Trace v3 states per tab

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/extension/src/lib/__tests__/recording-runtime.test.ts

@@ -11,11 +11,11 @@ vi.mock("../recording/observation-capture", async (importOriginal) => {
 import { ObservationNodeIndex } from "../recording/observation-capture";
 import { RecordingObservationRuntime } from "../recording/recording-runtime";
 
-function observation() {
+function observation(url = "https://example.com/") {
   return {
     rootFrameId: "root",
     index: new ObservationNodeIndex({ rootFrameId: "root", matchNodes: [], refs: [] }),
-    url: "https://example.com/",
+    url,
     title: "Example",
     vomText: '@vom 1\nRootWebArea "Example"',
     truncated: false,
@@ -130,4 +130,21 @@ describe("RecordingObservationRuntime", () => {
     expect(dumped).not.toContain("backendNodeId");
     expect(dumped).not.toContain("ObservationNodeIndex");
   });
+
+  it("captures a tab transition without sharing observation cursors", async () => {
+    captureRecordingObservation
+      .mockResolvedValueOnce(observation("https://example.com/first"))
+      .mockResolvedValueOnce(observation("https://example.com/second"));
+    const recording = runtime();
+
+    await recording.captureInitial(4);
+    const transition = await recording.captureTabTransition(4, 5);
+
+    expect(transition).toMatchObject({
+      preStateId: "s1",
+      postStateId: "s2",
+      targetUrl: "https://example.com/second",
+    });
+    expect(captureRecordingObservation.mock.calls.map(([input]) => input.tabId)).toEqual([4, 5]);
+  });
 });

apps/extension/src/lib/__tests__/step-buffer.test.ts

@@ -3,7 +3,7 @@ import { appendRecordedPayload, observeRecordedNavigation } from "../recording/s
 
 describe("recording-step-buffer", () => {
   it("stores semantic click without summary", () => {
-    const buffer = { steps: [], pendingNavigation: false };
+    const buffer = { steps: [], navigation: { pendingNavigation: false } };
     appendRecordedPayload(buffer, {
       op: "click",
       target: { tag: "button", role: "button", name: "发布" },
@@ -15,11 +15,11 @@ describe("recording-step-buffer", () => {
         captureTarget: { tag: "button", role: "button", name: "发布" },
       },
     ]);
-    expect(buffer.pendingNavigation).toBe(true);
+    expect(buffer.navigation.pendingNavigation).toBe(true);
   });
 
   it("keeps the hovered element description as a capture fallback", () => {
-    const buffer = { steps: [], pendingNavigation: false };
+    const buffer = { steps: [], navigation: { pendingNavigation: false } };
     appendRecordedPayload(
       buffer,
       {
@@ -59,9 +59,11 @@ describe("recording-step-buffer", () => {
           captureTarget: { tag: "button", role: "button", name: "发布" },
         },
       ],
-      currentUrl: "https://example.com/a",
-      pendingNavigation: true,
-      pendingNavigationDeadline: Date.now() + 5_000,
+      navigation: {
+        currentUrl: "https://example.com/a",
+        pendingNavigation: true,
+        pendingNavigationDeadline: Date.now() + 5_000,
+      },
     };
     observeRecordedNavigation(buffer, "https://example.com/b", true);
     expect(buffer.steps).toEqual([
@@ -83,9 +85,11 @@ describe("recording-step-buffer", () => {
           values: ["tech"],
         },
       ],
-      currentUrl: "https://example.com/list",
-      pendingNavigation: true,
-      pendingNavigationDeadline: Date.now() + 5_000,
+      navigation: {
+        currentUrl: "https://example.com/list",
+        pendingNavigation: true,
+        pendingNavigationDeadline: Date.now() + 5_000,
+      },
     };
     observeRecordedNavigation(buffer, "https://example.com/list?cat=tech", true);
     expect(buffer.steps).toEqual([
@@ -101,8 +105,7 @@ describe("recording-step-buffer", () => {
   it("emits navigate for uncaused URL changes", () => {
     const buffer = {
       steps: [],
-      currentUrl: "https://example.com/a",
-      pendingNavigation: false,
+      navigation: { currentUrl: "https://example.com/a", pendingNavigation: false },
     };
     const result = observeRecordedNavigation(buffer, "https://example.com/b", false);
     expect(result).toEqual({ kind: "appended", index: 0 });
@@ -115,8 +118,10 @@ describe("recording-step-buffer", () => {
   it("asks the recorder to coalesce redirect hops instead of emitting each one", () => {
     const buffer = {
       steps: [],
-      currentUrl: "https://passport.example/login",
-      pendingNavigation: false,
+      navigation: {
+        currentUrl: "https://passport.example/login",
+        pendingNavigation: false,
+      },
     };
     const hop1 = observeRecordedNavigation(
       buffer,
@@ -139,14 +144,16 @@ describe("recording-step-buffer", () => {
       url: "https://app.example/dashboard",
     });
     expect(buffer.steps).toEqual([]);
-    expect(buffer.currentUrl).toBe("https://app.example/dashboard");
+    expect(buffer.navigation.currentUrl).toBe("https://app.example/dashboard");
   });
 
   it("does not reuse redirect metadata for a later content-observed URL change", () => {
     const buffer = {
       steps: [],
-      currentUrl: "https://example.com/redirect",
-      pendingNavigation: false,
+      navigation: {
+        currentUrl: "https://example.com/redirect",
+        pendingNavigation: false,
+      },
     };
 
     const result = observeRecordedNavigation(buffer, "https://example.com/spa");

apps/extension/src/lib/__tests__/tab-coordinator.test.ts

@@ -0,0 +1,29 @@
+import { describe, expect, it } from "vitest";
+import { RecordingTabCoordinator } from "../recording/tab-coordinator";
+
+describe("RecordingTabCoordinator", () => {
+  it("keeps navigation state isolated per tab", () => {
+    const tabs = new RecordingTabCoordinator(4, "https://example.com/first");
+    const first = tabs.navigation(4);
+    first.pendingNavigation = true;
+    const second = tabs.navigation(5, "https://example.com/second");
+
+    expect(second).toEqual({
+      currentUrl: "https://example.com/second",
+      pendingNavigation: false,
+    });
+    expect(tabs.navigation(4)).toBe(first);
+    expect(tabs.navigation(4).pendingNavigation).toBe(true);
+  });
+
+  it("invalidates an earlier activation when a newer tab becomes active", () => {
+    const tabs = new RecordingTabCoordinator(4);
+    const second = tabs.noteActivation(5);
+    const third = tabs.noteActivation(6);
+
+    expect(tabs.isLatest(second)).toBe(false);
+    expect(tabs.isLatest(third)).toBe(true);
+    expect(tabs.commit(6)).toBe(4);
+    expect(tabs.currentTabId).toBe(6);
+  });
+});

apps/extension/src/lib/__tests__/trace-reducer-v2.test.ts

@@ -27,6 +27,17 @@ describe("shouldRecordPress", () => {
 });
 
 describe("reduceTraceSteps", () => {
+  it("does not expose internal tab transitions in trace v2", () => {
+    const trace = reduceTraceSteps([
+      {
+        op: "switch_tab",
+        preStateId: "s1",
+        postStateId: "s2",
+      },
+    ]);
+    expect(trace.steps).toEqual([]);
+  });
+
   it("builds steps with pages dictionary and page id references", () => {
     const drafts: RecordingDraftStep[] = [
       {

apps/extension/src/lib/__tests__/trace-reducer-v3.test.ts

@@ -33,6 +33,21 @@ describe("trace reducer v3", () => {
     expect(JSON.stringify(reduced.steps)).not.toContain("private-account-id");
   });
 
+  it("emits tab transitions only for callers that advertised support", () => {
+    const drafts: RecordingDraftStep[] = [
+      {
+        op: "switch_tab",
+        preStateId: "s1",
+        postStateId: "s2",
+      },
+    ];
+
+    expect(reduceTraceStepsV3(drafts).steps).toEqual([]);
+    expect(reduceTraceStepsV3(drafts, { includeTabSwitches: true }).steps).toEqual([
+      { op: "switch_tab", id: 1, state: "s1", result: { state: "s2" } },
+    ]);
+  });
+
   it("collapses redirect hops while retaining draft-to-step identity", () => {
     const drafts: RecordingDraftStep[] = [
       { op: "navigate", url: "https://example.com/start", preStateId: "s1", postStateId: "s2" },