Merge branch 'master' into fix/compact-before-model-switch

apps/web/tests/markdown-images.e2e.ts

@@ -166,7 +166,6 @@ describe('web e2e: Markdown image rendering', () => {
   let browser: Browser
   let page: Page
   let tripwire: ReturnType<typeof watchConsole>
-  let unpinBrowserClock: (() => void) | undefined
   const mediaResponses = new Map<string, number>()
 
   beforeAll(async () => {
@@ -191,7 +190,7 @@ describe('web e2e: Markdown image rendering', () => {
       { createdAt: WEB_FIXTURE_TIME - 60_000 })
     browser = await chromium.launch()
     page = await newEnglishPage(browser)
-    unpinBrowserClock = await pinBrowserClock(page)
+    await pinBrowserClock(page)
     tripwire = watchConsole(page)
     page.on('response', (response) => {
       const url = new URL(response.url())
@@ -204,7 +203,6 @@ describe('web e2e: Markdown image rendering', () => {
   }, 120_000)
 
   afterAll(async () => {
-    unpinBrowserClock?.()
     await browser?.close()
     await scaffold?.close()
     if (imageOrigin !== undefined) await stopServer(imageOrigin.server)

apps/web/tests/message-actions.e2e.ts

@@ -191,7 +191,6 @@ describe('web e2e: message IconActions and clocks on settled history', () => {
   let browser: Browser
   let page: Page
   let tripwire: ReturnType<typeof watchConsole>
-  let unpinBrowserClock: (() => void) | undefined
 
   beforeAll(async () => {
     scaffold = await launchWebScaffold()
@@ -212,14 +211,13 @@ describe('web e2e: message IconActions and clocks on settled history', () => {
     await seedSession(scaffold, raw, SEED_ID, undefined, { createdAt: WEB_FIXTURE_TIME - 90_000 })
     browser = await chromium.launch()
     page = await newEnglishPage(browser)
-    unpinBrowserClock = await pinBrowserClock(page)
+    await pinBrowserClock(page)
     tripwire = watchConsole(page)
     await page.goto(scaffold.authenticatedUrl, { waitUntil: 'load' })
     await page.waitForSelector('[class*="frame"]', { timeout: 30_000 })
   }, 120_000)
 
   afterAll(async () => {
-    unpinBrowserClock?.()
     await browser?.close()
     await scaffold?.close()
   })

apps/web/tests/pinned-clock.e2e.ts

@@ -0,0 +1,60 @@
+/** Fixture-day clock pins keep page scheduling native at every real-to-fixture distance. */
+import { chromium, type Browser } from 'playwright'
+import { afterAll, beforeAll, describe, expect, it, vi } from 'vitest'
+import { newEnglishPage, pinBrowserClock, WEB_FIXTURE_TIME } from './support.ts'
+
+// Host clock shifts spread over one 2^32 ms period of the real-to-fixture
+// distance; Playwright's page clock stopped page timers in half of that period.
+const DISTANCE_PERIOD_MS = 2 ** 32
+const HOST_SHIFTS_MS = Array.from({ length: 8 }, (_, index) => index * DISTANCE_PERIOD_MS / 8)
+
+describe('web e2e: pinned fixture clocks', () => {
+  let browser: Browser
+
+  beforeAll(async () => {
+    browser = await chromium.launch()
+  }, 120_000)
+
+  afterAll(async () => {
+    await browser?.close()
+  })
+
+  it.each(HOST_SHIFTS_MS)('runs page timers and reads the fixture day with the Host clock %d ms behind it', async (shift) => {
+    const hostStartedAt = performance.now()
+    const hostClock = vi.spyOn(Date, 'now').mockImplementation(() =>
+      WEB_FIXTURE_TIME - shift + Math.floor(performance.now() - hostStartedAt))
+    const page = await newEnglishPage(browser)
+    try {
+      await pinBrowserClock(page)
+      for (const navigation of ['initial', 'replacement']) {
+        await page.goto(`data:text/html,<body>${navigation}</body>`)
+        const pageStartedAt = await page.evaluate(() => {
+          requestAnimationFrame(() => { document.body.dataset.frame = 'done' })
+          setTimeout(() => { document.body.dataset.timer = 'done' }, 20)
+          return Date.now()
+        })
+        await expect.poll(() => page.evaluate(() => ({
+          frame: document.body.dataset.frame,
+          timer: document.body.dataset.timer,
+        })), { timeout: 5_000 }).toEqual({ frame: 'done', timer: 'done' })
+        const dates = await page.evaluate(() => ({
+          now: Date.now(),
+          day: new Date().toISOString().slice(0, 10),
+          explicit: new Date(0).getTime(),
+          parsed: Date.parse('2000-01-01T00:00:00Z'),
+        }))
+        expect(pageStartedAt).toBeGreaterThanOrEqual(WEB_FIXTURE_TIME)
+        expect(dates.now).toBeGreaterThan(pageStartedAt)
+        expect(dates.day).toBe(new Date(WEB_FIXTURE_TIME).toISOString().slice(0, 10))
+        expect(dates.explicit).toBe(0)
+        expect(dates.parsed).toBe(946_684_800_000)
+      }
+    } finally {
+      try {
+        await page.close()
+      } finally {
+        hostClock.mockRestore()
+      }
+    }
+  }, 60_000)
+})

apps/web/tests/reference-composer.e2e.ts

@@ -142,7 +142,6 @@ describe.skipIf(MODE === 'record')('web e2e: file and session references through
   let browser: Browser
   let page: Page
   let tripwire: ReturnType<typeof watchConsole>
-  let unpinBrowserClock: (() => void) | undefined
 
   beforeAll(async () => {
     scaffold = await launchWebScaffold({})
@@ -151,7 +150,7 @@ describe.skipIf(MODE === 'record')('web e2e: file and session references through
     await seedSession(scaffold, targetSessionFixture(), TARGET_SESSION_ID, undefined, { createdAt: targetCreatedAt })
     browser = await chromium.launch()
     page = await newEnglishPage(browser)
-    unpinBrowserClock = await pinBrowserClock(page)
+    await pinBrowserClock(page)
     tripwire = watchConsole(page)
     // Fixture files land before the workspace connects so the Host's file
     // index never races their creation (the connect helper mkdirs the same
@@ -171,7 +170,6 @@ describe.skipIf(MODE === 'record')('web e2e: file and session references through
   }, 120_000)
 
   afterAll(async () => {
-    unpinBrowserClock?.()
     await browser?.close()
     await scaffold?.close()
   })

apps/web/tests/seeded-history.e2e.ts

@@ -230,7 +230,6 @@ describe('web e2e: seeded history renders through cold resume', () => {
   let seededThroughSeq = -1
   let openingWindow: unknown
   let hostClock: ReturnType<typeof pinHostClock> | undefined
-  let unpinBrowserClock: (() => void) | undefined
 
   beforeAll(async () => {
     // Seeded and later command timestamps share the renderer's fixture day across midnight.
@@ -271,7 +270,7 @@ describe('web e2e: seeded history renders through cold resume', () => {
     }
     browser = await chromium.launch()
     page = await newEnglishPage(browser)
-    if (MODE !== 'record') unpinBrowserClock = await pinBrowserClock(page)
+    if (MODE !== 'record') await pinBrowserClock(page)
     tripwire = watchConsole(page)
     if (MODE !== 'record') {
       // A one-message tail makes this short recording exercise the real Load earlier path.
@@ -303,7 +302,6 @@ describe('web e2e: seeded history renders through cold resume', () => {
       await browser?.close()
       await scaffold?.close()
     } finally {
-      unpinBrowserClock?.()
       hostClock?.mockRestore()
     }
   })

apps/web/tests/steering.e2e.ts

@@ -73,7 +73,6 @@ describe('web e2e: mid-turn steering lands durably and visibly', () => {
   let page: Page
   let tripwire: ReturnType<typeof watchConsole>
   let hostClock: MockInstance<typeof Date.now> | undefined
-  let unpinBrowserClock: (() => void) | undefined
   const sessionEvents: SessionEvent[] = []
 
   beforeAll(async () => {
@@ -87,7 +86,7 @@ describe('web e2e: mid-turn steering lands durably and visibly', () => {
     scaffold.ctx.on('session/event', (_session, event) => { sessionEvents.push(event) })
     browser = await chromium.launch()
     page = await newEnglishPage(browser)
-    unpinBrowserClock = await pinBrowserClock(page)
+    await pinBrowserClock(page)
     tripwire = watchConsole(page)
     await page.goto(scaffold.authenticatedUrl, { waitUntil: 'load' })
     await page.waitForSelector('[class*="frame"]', { timeout: 30_000 })
@@ -101,8 +100,7 @@ describe('web e2e: mid-turn steering lands durably and visibly', () => {
       await scaffold?.close()
     } finally {
       // A failing close (unconsumed fixture, mismatched snapshot) must not
-      // leave the pinned clocks running for the suites after this one.
-      unpinBrowserClock?.()
+      // leave the pinned Host clock running for the suites after this one.
       hostClock?.mockRestore()
     }
   })
@@ -396,7 +394,6 @@ describe('web e2e: empty-draft Cmd+Enter steers the whole queue', () => {
   let page: Page
   let tripwire: ReturnType<typeof watchConsole>
   let hostClock: MockInstance<typeof Date.now> | undefined
-  let unpinBrowserClock: (() => void) | undefined
   const sessionEvents: SessionEvent[] = []
 
   beforeAll(async () => {
@@ -416,7 +413,7 @@ describe('web e2e: empty-draft Cmd+Enter steers the whole queue', () => {
     scaffold.ctx.on('session/event', (_session, event) => { sessionEvents.push(event) })
     browser = await chromium.launch()
     page = await newEnglishPage(browser)
-    unpinBrowserClock = await pinBrowserClock(page)
+    await pinBrowserClock(page)
     tripwire = watchConsole(page)
     await page.goto(scaffold.authenticatedUrl, { waitUntil: 'load' })
     await page.waitForSelector('[class*="frame"]', { timeout: 30_000 })
@@ -431,7 +428,6 @@ describe('web e2e: empty-draft Cmd+Enter steers the whole queue', () => {
       await browser?.close()
       await scaffold?.close()
     } finally {
-      unpinBrowserClock?.()
       hostClock?.mockRestore()
     }
   })

apps/web/tests/support.ts

@@ -50,9 +50,6 @@ export const WEB_FIXTURE_TIME = Date.parse('2026-01-15T12:00:00+08:00')
  */
 export const PLUGIN_TOGGLE_SETTLE_MS = 10_000
 
-/** How often a pinned browser clock advances, in milliseconds. */
-const PINNED_CLOCK_STEP_MS = 250
-
 /**
  * Pin the Host clock to the shared fixture day for one scenario suite.
  *
@@ -74,31 +71,36 @@ export function pinHostClock(): MockInstance<typeof Date.now> {
 }
 
 /**
- * Pin a scenario page's clock to the shared fixture day, advancing with real
+ * Pin a scenario page's calendar to the shared fixture day, advancing with real
  * time. Pair it with {@link pinHostClock} for a scenario that stamps its own
  * message times, and with `seedSession`'s `createdAt` for a seeded one.
  *
- * The frozen instant is re-applied from the anchor on an interval rather than
- * left at one value, because product logic reads two `Date.now()` values to
- * decide a minimum display hold or a deadline window; a permanently frozen
- * clock stops supplying elapsed time, so a title that owes its golden settled
- * text keeps rendering its previous one. Both clocks therefore advance at the
- * real rate and stay within one step of each other.
- * @param page - page whose clock is pinned.
- * @returns the disposer that stops re-pinning; call it in teardown.
+ * Only the page's `Date` reads the fixture day; native timers and
+ * `requestAnimationFrame` keep their real scheduling. Playwright's
+ * `page.clock` is not used: its server records clock state with the Vitest
+ * worker's `Date.now`, which {@link pinHostClock} replaces, so after a
+ * navigation the page clock replays the gap between the real and fixture days
+ * and hands the resulting negative delay to native `setTimeout`. The browser
+ * truncates that delay to a 32-bit integer, and in about half of the dates the
+ * result is a positive delay of weeks that stops every page timer. The `Date`
+ * override is installed for every later document and on the current one, and
+ * stays until the page closes.
+ * @param page - page whose calendar is pinned.
  */
-export async function pinBrowserClock(page: Page): Promise<() => void> {
-  const startedAt = Date.now()
-  const step = async (): Promise<void> => {
-    try {
-      await page.clock.setFixedTime(WEB_FIXTURE_TIME + (Date.now() - startedAt))
-    } catch {
-      // The page closed under the interval; teardown owns the last word.
-    }
+export async function pinBrowserClock(page: Page): Promise<void> {
+  // The worker's `new Date()` keeps the real clock even when `Date.now` is pinned.
+  const offset = WEB_FIXTURE_TIME - new Date().getTime()
+  const install = (offset: number): void => {
+    const NativeDate = Date
+    const now = (): number => NativeDate.now() + offset
+    globalThis.Date = new Proxy(NativeDate, {
+      construct: (target, args, newTarget): Date => Reflect.construct(target, args.length === 0 ? [now()] : args, newTarget) as Date,
+      apply: () => new NativeDate(now()).toString(),
+      get: (target, property, receiver): unknown => property === 'now' ? now : Reflect.get(target, property, receiver),
+    })
   }
-  await step()
-  const timer = setInterval(() => { void step() }, PINNED_CLOCK_STEP_MS)
-  return () => { clearInterval(timer) }
+  await page.addInitScript(install, offset)
+  await page.evaluate(install, offset)
 }
 
 /**