From cc1a524c34e63a470a0dc9dc41abcbef1cf399f9 Mon Sep 17 00:00:00 2001
From: MarsLuay <70299537+MarsLuay@users.noreply.github.com>
Date: Sun, 6 Sep 2026 04:37:11 +0000
Subject: [PATCH 1/2] test(idleSchedule): add coverage for edge cases

Added tests to handle `win.cancelIdleCallback` being undefined,
fallback timing bounds, and default options.
---
 tests/idle-schedule.test.mjs | 84 ++++++++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)

diff --git a/tests/idle-schedule.test.mjs b/tests/idle-schedule.test.mjs
index e5c1c45..227fd6c 100644
--- a/tests/idle-schedule.test.mjs
+++ b/tests/idle-schedule.test.mjs
@@ -111,3 +111,87 @@ test("scheduleIdleWork falls back to setTimeout when requestIdleCallback is unav
 
 	assert.equal(timeoutMs, 100, "uses timeout when it is smaller than 250");
 });
+
+test("scheduleIdleWork handles undefined cancelIdleCallback gracefully", async () => {
+	const { scheduleIdleWork } = await loadIdleScheduleModule();
+
+	let callbackCalled = false;
+	let requestedTimeout = -1;
+	let callbackFn = null;
+
+	globalThis.window = {
+		requestIdleCallback: (cb, opts) => {
+			callbackFn = cb;
+			requestedTimeout = opts?.timeout;
+			return 123;
+		},
+		cancelIdleCallback: undefined
+	};
+
+	const cancel = scheduleIdleWork(() => {
+		callbackCalled = true;
+	});
+
+	assert.equal(requestedTimeout, 2000, "uses default timeout of 2000");
+	assert.equal(typeof callbackFn, "function", "passed a callback function");
+
+	callbackFn();
+	assert.equal(callbackCalled, true, "callback is invoked");
+
+	cancel();
+	// Should not throw when cancelIdleCallback is undefined
+});
+
+test("scheduleIdleWork falls back to setTimeout with timeout over 250", async () => {
+	const { scheduleIdleWork } = await loadIdleScheduleModule();
+
+	let timeoutMs = -1;
+	let clearedId = -1;
+	let callbackFn = null;
+
+	globalThis.window = {
+		requestIdleCallback: undefined,
+		setTimeout: (cb, timeout) => {
+			callbackFn = cb;
+			timeoutMs = timeout;
+			return 999;
+		},
+		clearTimeout: (id) => {
+			clearedId = id;
+		}
+	};
+
+	let callbackCalled = false;
+	const cancel = scheduleIdleWork(() => {
+		callbackCalled = true;
+	}, { timeout: 1000 });
+
+	assert.equal(timeoutMs, 250, "uses Math.min(timeout, 250) for fallback timeout");
+	assert.equal(typeof callbackFn, "function", "passed a callback function");
+
+	callbackFn();
+	assert.equal(callbackCalled, true, "callback is invoked");
+
+	cancel();
+	assert.equal(clearedId, 999, "cancel returns correctly via clearTimeout");
+});
+
+test("scheduleIdleWork falls back to setTimeout without passing options", async () => {
+	const { scheduleIdleWork } = await loadIdleScheduleModule();
+
+	let timeoutMs = -1;
+
+	globalThis.window = {
+		requestIdleCallback: undefined,
+		setTimeout: (cb, timeout) => {
+			timeoutMs = timeout;
+			return 555;
+		},
+		clearTimeout: () => {}
+	};
+
+	scheduleIdleWork(() => {});
+
+	// options.timeout defaults to 2000, Math.min(2000, 250) is 250
+	assert.equal(timeoutMs, 250, "uses default timeout and caps at 250");
+});

From 84d85df28a36620c9cce80b80992ae8acc5b9a50 Mon Sep 17 00:00:00 2001
From: MarsLuay <70299537+MarsLuay@users.noreply.github.com>
Date: Sun, 6 Sep 2026 04:50:23 +0000
Subject: [PATCH 2/2] test(idleSchedule): add coverage for edge cases

Added tests to handle win.cancelIdleCallback being undefined,
fallback timing bounds, and default options.