From a38dc473dc7a46bdf9062cc17633c3385758e89c Mon Sep 17 00:00:00 2001
From: Vincent Koc <vincentkoc@ieee.org>
Date: Sun, 2 Aug 2026 01:06:14 +0800
Subject: [PATCH] fix(google): make continuity reset generation-idempotent

---
 .../google/realtime-voice-provider.test.ts    | 83 +++++++++++++++++++
 extensions/google/realtime-voice-provider.ts  |  9 +-
 2 files changed, 91 insertions(+), 1 deletion(-)

diff --git a/extensions/google/realtime-voice-provider.test.ts b/extensions/google/realtime-voice-provider.test.ts
index 8cc472ca6123..c01314c84ccb 100644
--- a/extensions/google/realtime-voice-provider.test.ts
+++ b/extensions/google/realtime-voice-provider.test.ts
@@ -1071,6 +1071,89 @@ describe("buildGoogleRealtimeVoiceProvider", () => {
     );
   });
 
+  it("emits one continuity reset across failed fresh reconnect attempts", async () => {
+    vi.useFakeTimers();
+    const provider = buildGoogleRealtimeVoiceProvider();
+    const onClose = vi.fn();
+    const onEvent = vi.fn();
+    const bridge = provider.createBridge({
+      providerConfig: { apiKey: "gemini-key", sessionResumption: false },
+      onAudio: vi.fn(),
+      onClearAudio: vi.fn(),
+      onClose,
+      onEvent,
+    });
+
+    await bridge.connect();
+    const firstSession = lastConnectParams().callbacks;
+    firstSession.onmessage({ setupComplete: {} });
+    connectMock
+      .mockRejectedValueOnce(new Error("connect failed 1"))
+      .mockRejectedValueOnce(new Error("connect failed 2"))
+      .mockRejectedValueOnce(new Error("connect failed 3"));
+    firstSession.onclose({ code: 1011, reason: "temporary" });
+
+    await vi.advanceTimersByTimeAsync(1_750);
+
+    expect(connectMock).toHaveBeenCalledTimes(4);
+    expect(onEvent.mock.calls).toEqual([
+      [{ direction: "client", type: "session.continuity.reset" }],
+    ]);
+    expect(onClose).toHaveBeenCalledWith("error");
+  });
+
+  it("rearms continuity reset after pre-return setup selects a fresh session", async () => {
+    vi.useFakeTimers();
+    const pendingSession = createDeferred<MockGoogleLiveSession>();
+    const freshSession = createMockGoogleLiveSession();
+    connectMock
+      .mockReturnValueOnce(Promise.resolve(session))
+      .mockReturnValueOnce(pendingSession.promise);
+    const provider = buildGoogleRealtimeVoiceProvider();
+    const onEvent = vi.fn();
+    const onReady = vi.fn();
+    const onTranscript = vi.fn();
+    const bridge = provider.createBridge({
+      providerConfig: { apiKey: "gemini-key", sessionResumption: false },
+      onAudio: vi.fn(),
+      onClearAudio: vi.fn(),
+      onEvent,
+      onReady,
+      onTranscript,
+    });
+
+    await bridge.connect();
+    const firstCallbacks = lastConnectParams().callbacks;
+    firstCallbacks.onopen();
+    firstCallbacks.onmessage({ setupComplete: {} });
+    firstCallbacks.onclose({ code: 1011, reason: "temporary" });
+    await vi.advanceTimersByTimeAsync(250);
+
+    const freshCallbacks = lastConnectParams().callbacks;
+    expect(onEvent).toHaveBeenCalledTimes(1);
+    freshCallbacks.onopen();
+    freshCallbacks.onmessage({
+      setupComplete: {},
+      serverContent: { inputTranscription: { text: "Fresh partial " } },
+    });
+    expect(onReady).toHaveBeenCalledTimes(1);
+
+    pendingSession.resolve(freshSession);
+    await vi.waitFor(() => {
+      expect(onReady).toHaveBeenCalledTimes(2);
+    });
+    freshCallbacks.onclose({ code: 1011, reason: "temporary again" });
+    await vi.advanceTimersByTimeAsync(250);
+
+    expect(onEvent).toHaveBeenCalledTimes(2);
+    lastConnectParams().callbacks.onmessage({
+      serverContent: { inputTranscription: { text: "Next", finished: true } },
+    });
+    expect(onTranscript.mock.calls.filter((call) => call[2] === true)).toEqual([
+      ["user", "Next", true],
+    ]);
+  });
+
   it("waits for the returned session after setup completion before activating", async () => {
     const pendingSession = createDeferred<MockGoogleLiveSession>();
     const connectedSession = createMockGoogleLiveSession();
diff --git a/extensions/google/realtime-voice-provider.ts b/extensions/google/realtime-voice-provider.ts
index dbfeec2c4878..89c1715d33f4 100644
--- a/extensions/google/realtime-voice-provider.ts
+++ b/extensions/google/realtime-voice-provider.ts
@@ -482,6 +482,7 @@ class GoogleRealtimeVoiceBridge implements RealtimeVoiceBridge {
   private reconnectAttempts = 0;
   private reconnectTimer: ReturnType<typeof setTimeout> | undefined;
   private hasConnectedSession = false;
+  private continuityResetEmitted = false;
   private terminalError: Error | undefined;
   private closeNotified = false;
   private connectionOwner: GoogleLiveConnectionAttempt | undefined;
@@ -532,10 +533,11 @@ class GoogleRealtimeVoiceBridge implements RealtimeVoiceBridge {
   private async connectOwned(attempt: GoogleLiveConnectionAttempt): Promise<void> {
     const canResumeSession =
       this.config.sessionResumption !== false && Boolean(this.resumptionHandle);
-    if (this.hasConnectedSession && !canResumeSession) {
+    if (this.hasConnectedSession && !canResumeSession && !this.continuityResetEmitted) {
       // An unfinished recognition hypothesis cannot cross into a fresh server session.
       // Notify consumers before connect because the SDK can replay fresh-session
       // callbacks before its connect promise returns.
+      this.continuityResetEmitted = true;
       this.resetPendingTranscripts();
       this.config.onEvent?.({
         direction: "client",
@@ -868,6 +870,11 @@ class GoogleRealtimeVoiceBridge implements RealtimeVoiceBridge {
   }
 
   private handleSetupComplete(): void {
+    if (!this.setupCompleteReceived) {
+      // setupComplete proves Google selected a new server session. A later
+      // continuity loss therefore owns a new reset generation.
+      this.continuityResetEmitted = false;
+    }
     this.setupCompleteReceived = true;
     this.maybeActivateSession();
   }