From f88b758e9c2c5e2396ee32e950fc39e740117206 Mon Sep 17 00:00:00 2001
From: probe <probe@local>
Date: Tue, 10 Nov 2026 19:41:28 +0800
Subject: [PATCH] test(webui): read the rail flyout's exit animation from the
 event it fires

The shared surface exit runs for 120ms and the flyout is unmounted when it
ends, so reading the element's computed animation-name after the exit state
has appeared is a race: on a loaded runner the read lands after the
animation has been cleaned up and sees an empty value, which says nothing
about whether the shared exit ran.

The sibling surfaces already read their exit from the animation event, which
is what happened rather than what one instant of the page looks like. The
expected values are unchanged: the exit state, the shared surface exit
animation, and the flyout going away.
---
 .../webui/test/browser/rail-archive.spec.mjs  | 27 +++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/packages/webui/test/browser/rail-archive.spec.mjs b/packages/webui/test/browser/rail-archive.spec.mjs
index db643c8ad..837b7c134 100644
--- a/packages/webui/test/browser/rail-archive.spec.mjs
+++ b/packages/webui/test/browser/rail-archive.spec.mjs
@@ -39,6 +39,27 @@ test("the rail context-menu flyout uses the shared surface exit lifecycle", asyn
   await configureFixture(page, () => undefined);
   await openApp(page);
   await page.emulateMedia({ reducedMotion: "no-preference" });
+  // The exit animation is read from the event it fires, the way the other
+  // surfaces read theirs. The shared exit runs for 120ms and the flyout is
+  // unmounted when it ends, so a style read that lands after that sees an
+  // element with nothing left on it and says nothing about whether the
+  // shared exit ran at all.
+  await page.evaluate(() => {
+    window.__railSubmenuExitAnimation = "";
+    document.addEventListener(
+      "animationstart",
+      (event) => {
+        if (
+          event.target instanceof HTMLElement &&
+          event.target.classList.contains("webui-context-menu-submenu") &&
+          event.animationName === "webui-motion-surface-exit"
+        ) {
+          window.__railSubmenuExitAnimation = event.animationName;
+        }
+      },
+      { capture: true },
+    );
+  });
   await sessionRow(page, "B").first().click({ button: "right", position: { x: 40, y: 16 } });
 
   const submenu = page.locator(".webui-context-menu-submenu");
@@ -49,8 +70,10 @@ test("the rail context-menu flyout uses the shared surface exit lifecycle", asyn
 
   await menuItem(page, "归档").hover();
   await expect(submenu).toHaveAttribute("data-webui-motion-state", "exit");
-  expect(await submenu.evaluate((node) => getComputedStyle(node).animationName)).toBe("webui-motion-surface-exit");
-  await expect(submenu).toHaveCount(0, { timeout: 500 });
+  await expect
+    .poll(() => page.evaluate(() => window.__railSubmenuExitAnimation))
+    .toBe("webui-motion-surface-exit");
+  await expect(submenu).toHaveCount(0);
 });
 
 /** Opens settings the way a user does: the user menu, then 设置. */