From 614e30a61adabcf8222252351e53e7fd2de6cd06 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Thu, 5 Feb 2026 23:04:21 +0000
Subject: [PATCH] fix(test): polyfill synchronous requestIdleCallback for unit
 tests

Fixes flaky/failing unit tests in `tests/state/profile-cache.test.mjs` caused by the recent optimization to defer `localStorage` writes using `requestIdleCallback`.

In the JSDOM environment, `requestIdleCallback` was missing, causing a fallback to `setTimeout`, which introduced asynchronous behavior that the existing tests did not account for.

This change adds a synchronous polyfill for `requestIdleCallback` in `tests/test-helpers/setup-localstorage.mjs`, ensuring that deferred writes happen immediately during testing, restoring deterministic behavior.

Co-authored-by: PR0M3TH3AN <53631862+PR0M3TH3AN@users.noreply.github.com>
---
 tests/test-helpers/setup-localstorage.mjs | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/tests/test-helpers/setup-localstorage.mjs b/tests/test-helpers/setup-localstorage.mjs
index ed24fc84..db67e7ac 100644
--- a/tests/test-helpers/setup-localstorage.mjs
+++ b/tests/test-helpers/setup-localstorage.mjs
@@ -44,6 +44,16 @@ if (typeof globalThis.window.localStorage === "undefined") {
   globalThis.window.localStorage = globalThis.localStorage;
 }
 
+// Polyfill requestIdleCallback for synchronous testing if undefined
+if (typeof globalThis.requestIdleCallback === "undefined") {
+  globalThis.requestIdleCallback = (cb) => cb();
+  globalThis.cancelIdleCallback = () => {};
+  if (globalThis.window) {
+    globalThis.window.requestIdleCallback = globalThis.requestIdleCallback;
+    globalThis.window.cancelIdleCallback = globalThis.cancelIdleCallback;
+  }
+}
+
 if (typeof globalThis.window.crypto === "undefined" && typeof globalThis.crypto !== "undefined") {
   globalThis.window.crypto = globalThis.crypto;
 }