From 56cddc6ad610e46de9167983f8b0423abf3ef92d Mon Sep 17 00:00:00 2001
From: Edo Z <0xe1216@gmail.com>
Date: Wed, 30 Sep 2026 16:34:17 +0400
Subject: [PATCH] perf: skip hidden notification progress updates

---
 src/Notification.tsx                  |  17 +++-
 tests/notification-rendering.test.tsx | 119 ++++++++++++++++++++++++++
 2 files changed, 134 insertions(+), 2 deletions(-)
 create mode 100644 tests/notification-rendering.test.tsx

diff --git a/src/Notification.tsx b/src/Notification.tsx
index 0f68c54..4f13aec 100644
--- a/src/Notification.tsx
+++ b/src/Notification.tsx
@@ -1,7 +1,7 @@
 import * as React from 'react';
 import { clsx } from 'clsx';
 import useNoticeTimer from './hooks/useNoticeTimer';
-import { isNonNullable, isReactRenderable, useEvent } from '@rc-component/util';
+import { isNonNullable, isReactRenderable, useEvent, useLayoutEffect } from '@rc-component/util';
 import useClosable, { type ClosableType } from './hooks/useClosable';
 import DefaultProgress from './Progress';
 import type { NotificationProgressProps } from './Progress';
@@ -106,6 +106,7 @@ const Notification = React.forwardRef<HTMLDivElement, NotificationProps>((props,
   } = props;
 
   const [percent, setPercent] = React.useState(0);
+  const percentRef = React.useRef(0);
   const noticePrefixCls = `${prefixCls}-notice`;
 
   // ========================= Close ==========================
@@ -118,7 +119,19 @@ const Notification = React.forwardRef<HTMLDivElement, NotificationProps>((props,
   // ======================== Duration ========================
   const [hovering, setHovering] = React.useState(false);
 
-  const [onResume, onPause] = useNoticeTimer(duration, onInternalClose, setPercent);
+  const [onResume, onPause] = useNoticeTimer(duration, onInternalClose, (nextPercent) => {
+    percentRef.current = nextPercent;
+    if (showProgress) {
+      setPercent(nextPercent);
+    }
+  });
+
+  // Progress can be enabled while paused, when no timer tick will update state.
+  useLayoutEffect(() => {
+    if (showProgress) {
+      setPercent(percentRef.current);
+    }
+  }, [showProgress]);
 
   const validPercent = 100 - Math.min(Math.max(percent * 100, 0), 100);
   const Progress = components?.progress || DefaultProgress;
diff --git a/tests/notification-rendering.test.tsx b/tests/notification-rendering.test.tsx
new file mode 100644
index 0000000..6374623
--- /dev/null
+++ b/tests/notification-rendering.test.tsx
@@ -0,0 +1,119 @@
+import { act, render } from '@testing-library/react';
+import React from 'react';
+import Notification from '../src/Notification';
+
+function advanceFrames(count: number) {
+  for (let frame = 0; frame < count; frame += 1) {
+    act(() => vi.advanceTimersByTime(16));
+  }
+}
+
+describe('Notification timer rendering', () => {
+  beforeEach(() => vi.useFakeTimers());
+  afterEach(() => vi.useRealTimers());
+
+  it.each([undefined, false])(
+    'does not render hidden progress on timer ticks (%s)',
+    (showProgress) => {
+      const onRender = vi.fn();
+      const onClose = vi.fn();
+      const { queryByRole, unmount } = render(
+        <React.Profiler id="notification" onRender={onRender}>
+          <Notification
+            prefixCls="rc-notification"
+            description="Notice"
+            duration={1}
+            showProgress={showProgress}
+            onClose={onClose}
+          />
+        </React.Profiler>,
+      );
+      const initialRenderCount = onRender.mock.calls.length;
+
+      advanceFrames(32);
+
+      expect(onRender).toHaveBeenCalledTimes(initialRenderCount);
+      expect(queryByRole('progressbar')).toBeNull();
+      expect(onClose).not.toHaveBeenCalled();
+
+      advanceFrames(32);
+      expect(onClose).toHaveBeenCalledTimes(1);
+      unmount();
+    },
+  );
+
+  it('continues rendering visible progress and closes at the original duration', () => {
+    const onClose = vi.fn();
+    const { getByRole, unmount } = render(
+      <Notification prefixCls="rc-notification" duration={1} showProgress onClose={onClose} />,
+    );
+
+    advanceFrames(32);
+    expect((getByRole('progressbar') as HTMLProgressElement).value).toBeCloseTo(48.8, 1);
+    expect(onClose).not.toHaveBeenCalled();
+
+    advanceFrames(32);
+    expect(onClose).toHaveBeenCalledTimes(1);
+    unmount();
+  });
+
+  it('updates progress when enabled during an existing countdown without restarting it', () => {
+    const onClose = vi.fn();
+    const onRender = vi.fn();
+    const notice = (showProgress: boolean) => (
+      <React.Profiler id="notification" onRender={onRender}>
+        <Notification
+          prefixCls="rc-notification"
+          duration={1}
+          showProgress={showProgress}
+          onClose={onClose}
+        />
+      </React.Profiler>
+    );
+    const { rerender, getByRole, unmount } = render(notice(false));
+
+    advanceFrames(16);
+    rerender(notice(true));
+    advanceFrames(16);
+    expect((getByRole('progressbar') as HTMLProgressElement).value).toBeCloseTo(48.8, 1);
+
+    rerender(notice(false));
+    const renderCount = onRender.mock.calls.length;
+    advanceFrames(16);
+    expect(onRender).toHaveBeenCalledTimes(renderCount);
+    expect(onClose).not.toHaveBeenCalled();
+
+    advanceFrames(16);
+    expect(onClose).toHaveBeenCalledTimes(1);
+    unmount();
+  });
+
+  it('shows elapsed progress when enabled while the countdown is paused', () => {
+    const onClose = vi.fn();
+    const notice = (showProgress: boolean, hovering: boolean) => (
+      <Notification
+        prefixCls="rc-notification"
+        duration={1}
+        showProgress={showProgress}
+        hovering={hovering}
+        onClose={onClose}
+      />
+    );
+    const { rerender, getByRole, unmount } = render(notice(false, false));
+
+    advanceFrames(16);
+    rerender(notice(false, true));
+    advanceFrames(32);
+    rerender(notice(true, true));
+
+    expect((getByRole('progressbar') as HTMLProgressElement).value).toBeCloseTo(74.4, 1);
+    advanceFrames(16);
+    expect((getByRole('progressbar') as HTMLProgressElement).value).toBeCloseTo(74.4, 1);
+    expect(onClose).not.toHaveBeenCalled();
+
+    rerender(notice(true, false));
+    advanceFrames(48);
+    expect(onClose).toHaveBeenCalledTimes(1);
+    unmount();
+  });
+});