fix(discord): guard gateway cleanup races

extensions/discord/src/monitor/gateway-supervisor.test.ts

@@ -85,4 +85,25 @@ describe("createDiscordGatewaySupervisor", () => {
     expect(() => supervisor.dispose()).not.toThrow();
     expect(() => supervisor.dispose()).not.toThrow();
   });
+
+  it("keeps suppressing late gateway errors after dispose", () => {
+    const emitter = new EventEmitter();
+    const runtime = { error: vi.fn() };
+    const supervisor = createDiscordGatewaySupervisor({
+      client: {
+        getPlugin: vi.fn(() => ({ emitter })),
+      } as never,
+      isDisallowedIntentsError: () => false,
+      runtime: runtime as never,
+    });
+
+    supervisor.dispose();
+
+    expect(() =>
+      emitter.emit("error", new Error("Max reconnect attempts (0) reached after code 1005")),
+    ).not.toThrow();
+    expect(runtime.error).toHaveBeenCalledWith(
+      expect.stringContaining("suppressed late gateway reconnect-exhausted error after dispose"),
+    );
+  });
 });

extensions/discord/src/monitor/gateway-supervisor.ts

@@ -94,14 +94,20 @@ export function createDiscordGatewaySupervisor(params: {
       ),
     );
   };
+  const logLateDisposedEvent = (event: DiscordGatewayEvent) => {
+    params.runtime.error?.(
+      danger(`discord: suppressed late gateway ${event.type} error after dispose: ${event.message}`),
+    );
+  };
   const onGatewayError = (err: unknown) => {
-    if (disposed) {
-      return;
-    }
     const event = classifyDiscordGatewayEvent({
       err,
       isDisallowedIntentsError: params.isDisallowedIntentsError,
     });
+    if (phase === "disposed") {
+      logLateDisposedEvent(event);
+      return;
+    }
     if (phase === "active" && lifecycleHandler) {
       lifecycleHandler(event);
       return;
@@ -145,7 +151,6 @@ export function createDiscordGatewaySupervisor(params: {
       lifecycleHandler = undefined;
       phase = "disposed";
       pending.length = 0;
-      emitter.removeListener("error", onGatewayError);
     },
   };
 }

extensions/discord/src/monitor/provider.test.ts

@@ -225,6 +225,26 @@ describe("monitorDiscordProvider", () => {
     expect(createdBindingManagers[0]?.stop).toHaveBeenCalledTimes(1);
   });
 
+  it("disconnects the gateway when startup fails before lifecycle begins after client creation", async () => {
+    const disconnect = vi.fn();
+    clientGetPluginMock.mockImplementation((name: string) =>
+      name === "gateway" ? { emitter: new EventEmitter(), disconnect, isConnected: false } : undefined,
+    );
+    createDiscordMessageHandlerMock.mockImplementationOnce(() => {
+      throw new Error("handler init failed");
+    });
+
+    await expect(
+      monitorDiscordProvider({
+        config: baseConfig(),
+        runtime: baseRuntime(),
+      }),
+    ).rejects.toThrow("handler init failed");
+
+    expect(monitorLifecycleMock).not.toHaveBeenCalled();
+    expect(disconnect).toHaveBeenCalledTimes(1);
+  });
+
   it("does not double-stop thread bindings when lifecycle performs cleanup", async () => {
     await monitorDiscordProvider({
       config: baseConfig(),

extensions/discord/src/monitor/provider.ts

@@ -797,6 +797,7 @@ export async function monitorDiscordProvider(opts: MonitorDiscordOpts = {}) {
   let gatewaySupervisor: ReturnType<typeof createDiscordGatewaySupervisor> | undefined;
   let deactivateMessageHandler: (() => void) | undefined;
   let autoPresenceController: ReturnType<typeof createDiscordAutoPresenceController> | null = null;
+  let lifecycleGateway: GatewayPlugin | undefined;
   let earlyGatewayEmitter = gatewaySupervisor?.emitter;
   let onEarlyGatewayDebug: ((msg: unknown) => void) | undefined;
   try {
@@ -954,7 +955,7 @@ export async function monitorDiscordProvider(opts: MonitorDiscordOpts = {}) {
       runtime,
     });
 
-    const lifecycleGateway = client.getPlugin<GatewayPlugin>("gateway");
+    lifecycleGateway = client.getPlugin<GatewayPlugin>("gateway");
     earlyGatewayEmitter = gatewaySupervisor.emitter;
     onEarlyGatewayDebug = (msg: unknown) => {
       if (!(isVerboseForTesting ?? isVerbose)()) {
@@ -1181,6 +1182,13 @@ export async function monitorDiscordProvider(opts: MonitorDiscordOpts = {}) {
     if (onEarlyGatewayDebug) {
       earlyGatewayEmitter?.removeListener("debug", onEarlyGatewayDebug);
     }
+    if (!lifecycleStarted) {
+      try {
+        lifecycleGateway?.disconnect();
+      } catch (err) {
+        runtime.error?.(danger(`discord: failed to disconnect gateway during startup cleanup: ${String(err)}`));
+      }
+    }
     gatewaySupervisor?.dispose();
     if (!lifecycleStarted) {
       threadBindings.stop();