From 5daf2adc60216831e0db569df799daff59a93789 Mon Sep 17 00:00:00 2001
From: qwen-code-dev-bot <qwen-code-dev-bot@users.noreply.github.com>
Date: Wed, 26 Aug 2026 20:54:49 +0000
Subject: [PATCH] fix(webui): make the delta-resume reconnect test
 deterministic (#10200)

The 'preserves session and uses delta resume after a retriable SSE
error' test asserted the resumed transcript after a fixed 20 ms wait
counted from render, racing two asynchronous hops: the 1 ms reconnect
and the 16 ms batched transcript dispatch. On loaded runners the
reconnect plus dispatch flush lands after the wait ends, so the
assertion saw only the pre-error chunk and the nightly macOS/Windows
lanes failed (run 33007778391, Windows annotation at
DaemonSessionProvider.test.tsx).

Wait on a deferred the mock generator resolves once the resumed chunk
is pulled by the consumer, then drain the batched dispatch with the
same flushTranscriptDispatch() idiom the sibling reattach test uses.
Assertions are unchanged.
---
 .../webui/src/daemon/session/DaemonSessionProvider.test.tsx  | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/packages/webui/src/daemon/session/DaemonSessionProvider.test.tsx b/packages/webui/src/daemon/session/DaemonSessionProvider.test.tsx
index e0cd89f6b21..572c9b4e536 100644
--- a/packages/webui/src/daemon/session/DaemonSessionProvider.test.tsx
+++ b/packages/webui/src/daemon/session/DaemonSessionProvider.test.tsx
@@ -12140,6 +12140,7 @@ describe('DaemonSessionProvider', () => {
   });
 
   it('preserves session and uses delta resume after a retriable SSE error', async () => {
+    const resumeDelivered = createDeferred<void>();
     let callCount = 0;
     const events = vi.fn(async function* retriableEvents(
       opts: { signal?: AbortSignal } = {},
@@ -12171,6 +12172,7 @@ describe('DaemonSessionProvider', () => {
           },
         },
       } satisfies DaemonEvent;
+      resumeDelivered.resolve();
       await new Promise<void>((resolve) => {
         if (opts.signal?.aborted) {
           resolve();
@@ -12196,8 +12198,9 @@ describe('DaemonSessionProvider', () => {
       maxReconnectDelayMs: 1,
     });
     await act(async () => {
-      await wait(20);
+      await resumeDelivered.promise;
       await flushPromises();
+      await flushTranscriptDispatch();
     });
 
     expect(sdkMocks.MockDaemonSessionClient.load).toHaveBeenCalledTimes(1);