test(e2e): robustness — stable locators, exact assertions, no fixed sleep

- ContextSheet: add data-testid="context-sheet". longpress tests targeted the
  open sheet via the `.translate-y-0` animation class (breaks on any animation
  refactor) — now target `[data-testid="context-sheet"][aria-modal="true"]`,
  which is stable and unambiguous vs. the centered LightboxModal (also aria-modal).
- toast-on-failure: the like button was `button.filter(hasText:/\d+/).first()`,
  which could match any digit-bearing button (e.g. the comment count) → use the
  stable aria-label "Gefällt mir".
- config stats: assert the exact user_count (4 = 3 seeded guests + admin) instead
  of `>= 3` — deterministic after the per-test truncate, catches under/overcount.
- offline-network 429 test: replace the fixed 3s waitForTimeout with a
  poll-until-the-retry-count-stabilizes (faster, and a real storm never stabilizes
  → the poll fails, which is the intended outcome).

Note: reviewed the "config restore not in try/finally" finding — it's a non-issue.
The truncate auto-fixture wipes+reseeds the whole config table (and clears the
rate limiter) before every test, so config state cannot leak between tests.

All affected specs verified green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

e2e/specs/03-feed/toast-on-failure.spec.ts

@@ -41,8 +41,9 @@ test.describe('Feed — error toast on user action failures', () => {
     const card = page.locator('article').filter({ hasText: author.displayName }).first();
     await expect(card).toBeVisible({ timeout: 10_000 });
 
-    // Click the like button in the actions row — first visible match inside the card.
-    await card.locator('button').filter({ hasText: /\d+/ }).first().click();
+    // Click the like button by its stable aria-label (the liker hasn't liked yet).
+    // Avoids matching a different digit-bearing button (e.g. the comment count).
+    await card.getByRole('button', { name: 'Gefällt mir' }).click();
 
     // The toast is rendered inside the global Toaster region with aria-live="polite".
     const toast = page.getByTestId('toast').first();

e2e/specs/05-admin/config.spec.ts

@@ -63,8 +63,10 @@ test.describe('Admin — stats', () => {
     await guest('Stat2');
     await guest('Stat3');
     const stats = await api.getStats(adminToken);
-    // Three guests + the Admin account auto-created on first admin login = 4 users.
-    expect(stats.user_count).toBeGreaterThanOrEqual(3);
+    // Deterministic after the per-test truncate: 3 seeded guests + the Admin account
+    // (recreated by the adminToken fixture's login) = exactly 4. An exact assertion
+    // catches undercount/overcount regressions a `>= 3` lower bound would miss.
+    expect(stats.user_count).toBe(4);
     expect(typeof stats.disk_total_bytes).toBe('number');
   });
 });

e2e/specs/08-browser-chaos/offline-network.spec.ts

@@ -72,9 +72,24 @@ test.describe('Browser chaos — network', () => {
 
     await signIn(page, g);
     await page.goto('/feed');
-    await page.waitForTimeout(3_000);
+
+    // Wait until the retry count stops climbing instead of sleeping a fixed 3s: a
+    // well-behaved client surfaces the 429 and stops, so the count settles quickly;
+    // a retry storm would keep incrementing and never stabilize (→ this poll times
+    // out and the test fails, which is the outcome we want).
+    let prev = -1;
+    await expect
+      .poll(
+        () => {
+          const stable = attempts === prev;
+          prev = attempts;
+          return stable;
+        },
+        { timeout: 8_000, intervals: [300] }
+      )
+      .toBe(true);
 
     // Sanity: client did not hammer the endpoint > a few times under throttle.
-    expect(attempts).toBeLessThan(15);
+    expect(attempts, `retry attempts=${attempts}`).toBeLessThan(15);
   });
 });

e2e/specs/09-mobile/gestures-longpress.spec.ts

@@ -45,13 +45,11 @@ test.describe('Mobile — long-press gesture', () => {
 
     await longPress(page, card, 600);
 
-    // The ContextSheet renders a dialog with role="dialog" + aria-modal="true".
-    // Multiple sheets (UploadSheet, ContextSheet) may be in the DOM — match the
-    // one that actually has aria-modal=true (i.e. the open one).
-    // ContextSheet is always mounted (it just translates off-screen when closed).
-    // Match the OPEN state by the `translate-y-0` class the component applies
-    // when `open === true`.
-    const sheet = page.locator('[role="dialog"][aria-modal="true"].translate-y-0');
+    // The ContextSheet is always mounted (it translates off-screen when closed).
+    // Target it by its stable data-testid, gated on aria-modal="true" which the
+    // component sets only while open — unambiguous vs. the centered LightboxModal
+    // (which also has aria-modal) and independent of the animation classes.
+    const sheet = page.locator('[data-testid="context-sheet"][aria-modal="true"]');
     await expect(sheet).toBeVisible({ timeout: 2_000 });
     await expect(sheet.getByRole('button', { name: /abbrechen/i })).toBeVisible();
   });
@@ -68,10 +66,9 @@ test.describe('Mobile — long-press gesture', () => {
     // Simulate a short press (200 ms — well under the 500 ms threshold).
     await longPress(page, card, 200);
 
-    // Within 1 s, no aria-modal=true dialog should be open (the ContextSheet
-    // is "open" only when its aria-modal flag is true).
-    // The ContextSheet stays mounted but `translate-y-0` is only set when open.
-    await expect(page.locator('[role="dialog"][aria-modal="true"].translate-y-0')).toHaveCount(0, { timeout: 1_000 });
+    // Within 1 s, the ContextSheet must not be open (aria-modal is set only when
+    // open). A quick tap opens the lightbox instead, which is a different element.
+    await expect(page.locator('[data-testid="context-sheet"][aria-modal="true"]')).toHaveCount(0, { timeout: 1_000 });
   });
 
   test('long-press suppresses the click that lands at pointerup (no double-open of lightbox)', async ({ page, guest, signIn }) => {

frontend/src/lib/components/ContextSheet.svelte

@@ -108,6 +108,7 @@
 	aria-hidden={!open}
 	inert={!open}
 	tabindex="-1"
+	data-testid="context-sheet"
 >
 	<div class="flex justify-center pt-3 pb-1">
 		<div class="h-1 w-10 rounded-full bg-gray-300 dark:bg-gray-600"></div>