test(ui): проверить отмену потока при смене сервера

tests/e2e/traffic-flow.spec.ts

@@ -190,3 +190,35 @@ test('Flow: интерфейс прежнего сервера не переда
   await expect(page.getByText('Второй сервер', { exact: true }).filter({ visible: true })).toBeVisible()
   await expect(page.getByText('Категория 15m', { exact: true })).toHaveCount(0)
 })
+
+test('Flow: смена сервера отменяет старую SSE-подписку', async ({ page }) => {
+  await setup(page)
+  await page.getByRole('button', { name: '15м', exact: true }).click()
+  await expect(page.getByText('Категория 15m', { exact: true }).filter({ visible: true })).toBeVisible()
+  let release = () => {}
+  const gate = new Promise<void>(resolve => { release = resolve })
+  let completed = () => {}
+  const delivered = new Promise<void>(resolve => { completed = resolve })
+  await page.route('**/api/traffic/flow/live?**', async route => {
+    const old = new URL(route.request().url()).searchParams.get('serverId') === '1'
+    if (old) await gate
+    const sample = { bpsNow: old ? 99000000 : 7000000, bytes: 200, packets: 2, conversations: 1, uniqueSrc: 1, uniqueDst: 1, topProto: 'TCP', topCategory: old ? 'SSE прежнего сервера' : 'SSE текущего сервера', rxSeries: [1], txSeries: [2], applications: [], protocols: [], sources: [], destinations: [], interfaces: [], conversationsList: [], ifaces: [], live: true }
+    try {
+      await route.fulfill({ contentType: 'text/event-stream', body: 'event: sample\ndata: ' + JSON.stringify(sample) + '\n\n' })
+    } finally {
+      if (old) completed()
+    }
+  })
+  const oldRequest = page.waitForRequest(r => r.url().includes('/flow/live?') && r.url().includes('serverId=1'))
+  await page.getByRole('button', { name: '5м', exact: true }).click()
+  await oldRequest
+  const aborted = page.waitForEvent('requestfailed', r => r.url().includes('/flow/live?') && r.url().includes('serverId=1'))
+  await page.getByRole('button').filter({ hasText: 'Экспортёр второй' }).click()
+  await aborted
+  await expect(page.getByText('SSE текущего сервера', { exact: true }).filter({ visible: true })).toBeVisible()
+  release()
+  await delivered
+  await expect(page.getByText('SSE прежнего сервера', { exact: true })).toHaveCount(0)
+  await expect(page.getByText('SSE текущего сервера', { exact: true }).filter({ visible: true })).toBeVisible()
+  await expect(page.getByLabel('Скорость потоков')).toContainText('7.00 Мбит/с')
+})