test: date fixtures that feed a clock-relative window relative to now

A fixture dated near the day it was written passes until the date slides
out of a window the route counts back from the clock. Five did: a snooze
until a fixed date that becomes the past in January, a prognosis read
against the wall clock over days seeded at a fixed date, sleep rows and a
weight streak read through windows that end now, and a sync token that
would expire on a fixed date. The e2e mood heatmap mock and a timeline
URL are dated from today as well.

A guard scans the integration and e2e trees for near-now absolute dates
within reach of a window parameter, with an allowlist for files whose
windows are fixed on both ends.

tests/integration/google-health-sync-progress.test.ts

@@ -42,7 +42,9 @@ async function seedConnection(userId: string): Promise<void> {
       googleUserId: `google-${userId}`,
       accessToken: "encrypted-access",
       refreshToken: "encrypted-refresh",
-      tokenExpiresAt: new Date("2027-01-01T00:00:00.000Z"),
+      // Valid for a year from whenever the suite runs: a fixed date would
+      // expire and send the sync down the refresh path.
+      tokenExpiresAt: new Date(Date.now() + 365 * 86_400_000),
     },
   });
 }

tests/integration/mood-prognosis-ladder.test.ts

@@ -15,7 +15,7 @@
  * tooltip.
  */
 import { NextRequest } from "next/server";
-import { beforeEach, describe, expect, it, vi } from "vitest";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 
 import { cookieJar } from "./mock-next-headers";
 import { getPrismaClient, switchSessionTo, truncateAllTables } from "./setup";
@@ -46,7 +46,14 @@ vi.mock("@/lib/db-compat", () => ({
 }));
 
 /** Fixed clock: a ladder test that slides with the calendar is a date bomb. */
-const NOW = new Date("2026-08-08T09:00:00.000Z");
+const FIXED_NOW = new Date("2026-08-08T09:00:00.000Z");
+/**
+ * The instant the seed and the job are dated against. The ladder cases keep
+ * the fixed clock; the route cases move it to the real one, because the route
+ * reads the forecast against the wall clock and a forecast seeded at a fixed
+ * date goes stale under it as the calendar moves on.
+ */
+let NOW = FIXED_NOW;
 
 function dayKey(daysAgo: number): string {
   return new Date(NOW.getTime() - daysAgo * DAY_MS).toISOString().slice(0, 10);
@@ -271,6 +278,13 @@ describe("the minimum-n ladder, end to end", () => {
 });
 
 describe("GET /api/mood/prognosis", () => {
+  beforeEach(() => {
+    NOW = new Date();
+  });
+  afterEach(() => {
+    NOW = FIXED_NOW;
+  });
+
   /**
    * A signed-in browser session.
    *

tests/integration/sharing-manage-handler-matrix.test.ts

@@ -795,7 +795,12 @@ manageContract("POST /api/measurement-reminders/[id]/snooze", {
       POST as Handler,
       "POST",
       `/api/measurement-reminders/${row.id}/snooze`,
-      { until: "2027-01-15" },
+      // A snooze must end in the future; a fixed date stops being one.
+      {
+        until: new Date(Date.now() + 90 * 86_400_000)
+          .toISOString()
+          .slice(0, 10),
+      },
       { id: row.id },
     );
   },

tests/integration/source-priority-two-axis.test.ts

@@ -34,6 +34,15 @@ import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import { cookieJar, headerJar } from "./mock-next-headers";
 import { getPrismaClient, truncateAllTables } from "./setup";
 
+/**
+ * The night the fixtures sleep, ten days back from whenever the suite runs.
+ * The analytics route summarises a window that ends now; a fixed date slides
+ * out of it as the calendar moves on.
+ */
+const SLEEP_DAY = new Date(Date.now() - 10 * 86_400_000)
+  .toISOString()
+  .slice(0, 10);
+
 vi.mock("next/headers", async () => {
   const { cookieJar, headerJar } = await import("./mock-next-headers");
   return {
@@ -130,7 +139,7 @@ describe("GET /api/analytics — two-axis canonical source resolution (W8c)", ()
         value: 420,
         unit: "minutes",
         source: "WITHINGS",
-        measuredAt: new Date("2026-05-12T07:00:00.000Z"),
+        measuredAt: new Date(`${SLEEP_DAY}T07:00:00.000Z`),
       },
     });
 
@@ -162,7 +171,7 @@ describe("GET /api/analytics — two-axis canonical source resolution (W8c)", ()
         value: 480,
         unit: "minutes",
         source: "APPLE_HEALTH",
-        measuredAt: new Date("2026-05-12T06:00:00.000Z"),
+        measuredAt: new Date(`${SLEEP_DAY}T06:00:00.000Z`),
         externalId: "ah-sleep-1",
       },
     });
@@ -174,7 +183,7 @@ describe("GET /api/analytics — two-axis canonical source resolution (W8c)", ()
         value: 410,
         unit: "minutes",
         source: "WITHINGS",
-        measuredAt: new Date("2026-05-12T07:00:00.000Z"),
+        measuredAt: new Date(`${SLEEP_DAY}T07:00:00.000Z`),
       },
     });
 
@@ -200,7 +209,7 @@ describe("GET /api/analytics — two-axis canonical source resolution (W8c)", ()
         value: 380,
         unit: "minutes",
         source: "APPLE_HEALTH",
-        measuredAt: new Date("2026-05-12T06:00:00.000Z"),
+        measuredAt: new Date(`${SLEEP_DAY}T06:00:00.000Z`),
         externalId: "ah-sleep-watch",
         deviceType: "watch",
       },
@@ -212,7 +221,7 @@ describe("GET /api/analytics — two-axis canonical source resolution (W8c)", ()
         value: 480,
         unit: "minutes",
         source: "APPLE_HEALTH",
-        measuredAt: new Date("2026-05-12T06:30:00.000Z"),
+        measuredAt: new Date(`${SLEEP_DAY}T06:30:00.000Z`),
         externalId: "ah-sleep-phone",
         deviceType: "phone",
       },
@@ -240,7 +249,7 @@ describe("GET /api/analytics — two-axis canonical source resolution (W8c)", ()
         value: 480,
         unit: "minutes",
         source: "APPLE_HEALTH",
-        measuredAt: new Date("2026-05-12T06:00:00.000Z"),
+        measuredAt: new Date(`${SLEEP_DAY}T06:00:00.000Z`),
         externalId: "ah-sleep-watch",
         deviceType: "watch",
       },
@@ -252,7 +261,7 @@ describe("GET /api/analytics — two-axis canonical source resolution (W8c)", ()
         value: 380,
         unit: "minutes",
         source: "APPLE_HEALTH",
-        measuredAt: new Date("2026-05-12T06:30:00.000Z"),
+        measuredAt: new Date(`${SLEEP_DAY}T06:30:00.000Z`),
         externalId: "ah-sleep-phone",
         deviceType: "phone",
       },

tests/integration/timezone-per-user.test.ts

@@ -420,8 +420,15 @@ describe("per-user timezone — Pacific/Auckland end-to-end", () => {
     // doesn't trigger a tz divergence on its own. The point is to
     // confirm the route returns a non-zero streak and goes through
     // the user-tz path without crashing.
+    // Three consecutive days ending a week back: the summary reads its
+    // streaks from a window that ends now, so fixed dates would slide out.
+    const firstDay = Date.UTC(
+      new Date().getUTCFullYear(),
+      new Date().getUTCMonth(),
+      new Date().getUTCDate() - 9,
+    );
     for (let i = 0; i < 3; i++) {
-      const dt = new Date(`2026-05-${12 + i}T11:30:00.000Z`);
+      const dt = new Date(firstDay + i * 86_400_000 + 11.5 * 3_600_000);
       await prisma.measurement.create({
         data: {
           userId: me.id,