fix(app): make session navigation stable and fast (#33569)

Co-authored-by: Brendan Allan <git@brendonovich.dev>
2026-06-24 07:48:54 +00:00
parent abcfeb380b
commit a4551a94b4
29 changed files with 1028 additions and 202 deletions
@@ -0,0 +1,85 @@
+import type { Page } from "@playwright/test"
+import { summarizeFirstNavigation, type FirstNavigationSample } from "./first-navigation-metrics"
+
+type FirstNavigationProbe = {
+  samples: FirstNavigationSample[]
+  stop: () => void
+}
+
+export async function measureFirstNavigation(
+  page: Page,
+  input: {
+    href: string
+    destinationPath: string
+    sourceSelector: string
+    destinationSelector: string
+    contentSelector: string
+    navigate: () => Promise<void>
+  },
+) {
+  await page.evaluate(
+    ({ href, destinationPath, sourceSelector, destinationSelector, contentSelector }) => {
+      const samples: FirstNavigationSample[] = []
+      let started: number | undefined
+      let running = true
+      const visible = (selector: string) =>
+        [...document.querySelectorAll<HTMLElement>(selector)].some((element) => {
+          const rect = element.getBoundingClientRect()
+          const style = getComputedStyle(element)
+          return rect.width > 0 && rect.height > 0 && style.visibility !== "hidden" && style.display !== "none"
+        })
+      const sample = () => {
+        if (!running || started === undefined) return
+        requestAnimationFrame(() => {
+          setTimeout(() => {
+            if (!running || started === undefined) return
+            samples.push({
+              observedAtMs: performance.now() - started,
+              source: visible(sourceSelector),
+              destination: `${location.pathname}${location.search}` === destinationPath && visible(destinationSelector),
+              content: visible(contentSelector),
+              pathname: `${location.pathname}${location.search}`,
+              center: document.elementFromPoint(innerWidth / 2, innerHeight / 2)?.textContent?.slice(0, 80),
+            })
+            sample()
+          }, 0)
+        })
+      }
+      document.addEventListener(
+        "click",
+        (event) => {
+          const link = event.target instanceof Element ? event.target.closest("a") : undefined
+          if (link?.getAttribute("href") !== href) return
+          started = performance.now()
+          sample()
+        },
+        { capture: true, once: true },
+      )
+      ;(window as Window & { __firstNavigationProbe?: FirstNavigationProbe }).__firstNavigationProbe = {
+        samples,
+        stop: () => {
+          running = false
+        },
+      }
+    },
+    {
+      href: input.href,
+      destinationPath: input.destinationPath,
+      sourceSelector: input.sourceSelector,
+      destinationSelector: input.destinationSelector,
+      contentSelector: input.contentSelector,
+    },
+  )
+  await input.navigate()
+  await page.waitForFunction(() => {
+    const samples = (window as Window & { __firstNavigationProbe?: FirstNavigationProbe }).__firstNavigationProbe?.samples
+    if (!samples) return false
+    return samples.length >= 3 && samples.slice(-3).every((sample) => sample.destination && !sample.source)
+  })
+  const samples = await page.evaluate(() => {
+    const probe = (window as Window & { __firstNavigationProbe?: FirstNavigationProbe }).__firstNavigationProbe!
+    probe.stop()
+    return probe.samples
+  })
+  return { summary: summarizeFirstNavigation(samples), samples }
+}