Conversation
- Added `requestAnimationFrame` to throttle scroll event handlers in `Layout`, `DynamicHeaderWrapper`, and `BackToTop` components.
- Added `{ passive: true }` option to the event listeners to avoid blocking the main thread.
- Updated related unit tests to mock `requestAnimationFrame`.
- Added a journal entry to `.jules/bolt.md` detailing the optimization.
Co-authored-by: anyulled <100741+anyulled@users.noreply.github.com>
|
👋 Jules, reporting for duty! I'm here to lend a hand with this pull request. When you start a review, I'll add a 👀 emoji to each comment to let you know I've read it. I'll focus on feedback directed at me and will do my best to stay out of conversations between you and other bots or reviewers to keep the noise down. I'll push a commit with your requested changes shortly after. Please note there might be a delay between these steps, but rest assured I'm on the job! For more direct control, you can switch me to Reactive Mode. When this mode is on, I will only act on comments where you specifically mention me with New to Jules? Learn more at jules.google/docs. For security, I will only act on instructions from the user who triggered this task. |
|
The latest updates on your projects. Learn more about Vercel for GitHub.
|
Summary of ChangesHello, I'm Gemini Code Assist1! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed! This pull request significantly enhances the application's scrolling performance and responsiveness. By introducing Highlights
Changelog
Activity
Using Gemini Code AssistThe full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips. Invoking Gemini You can request assistance from Gemini at any point by creating a comment using either
Customization To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a Limitations & Feedback Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for GitHub and other Google products, sign up here. You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension. Footnotes
|
Review Summary by QodoThrottle scroll listeners with requestAnimationFrame
WalkthroughsDescription• Throttle scroll event listeners using requestAnimationFrame in three components
• Add { passive: true } option to prevent main-thread blocking
• Implement state-based throttling mechanism to limit update frequency
• Update unit tests to mock requestAnimationFrame for proper testing
Diagramflowchart LR
A["Scroll Events<br/>60+ per second"] -->|"Throttle with<br/>requestAnimationFrame"| B["Deferred State<br/>Updates"]
B -->|"Passive Listeners<br/>{ passive: true }"| C["Smooth 60fps<br/>Scrolling"]
D["Layout<br/>DynamicHeaderWrapper<br/>BackToTop"] -->|"Apply Pattern"| E["Optimized<br/>Components"]
File Changes1. .jules/bolt.md
|
Code Review by Qodo
1. AOS init on scroll
|
📝 WalkthroughWalkthroughThis PR implements scroll event throttling using Changes
Poem
Estimated code review effort🎯 3 (Moderate) | ⏱️ ~20 minutes 🚥 Pre-merge checks | ✅ 2 | ❌ 1❌ Failed checks (1 warning)
✅ Passed checks (2 passed)
✏️ Tip: You can configure your own custom pre-merge checks in the settings. ✨ Finishing Touches
🧪 Generate unit tests (beta)
📝 Coding Plan
Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out. Comment |
![gemini-code-assist[bot]](https://avatars.githubusercontent.com/in/956858?s=60&v=4){kind=small}
There was a problem hiding this comment.
Code Review
This pull request is a great performance enhancement, throttling scroll event listeners using requestAnimationFrame and adding { passive: true }. The changes are well-implemented across the Layout, DynamicHeaderWrapper, and BackToTop components, and the test updates are solid. I've identified a couple of minor improvements in DynamicHeaderWrapper.tsx and Layout.tsx to optimize the useEffect hooks and prevent unnecessary re-attachment of event listeners, which will make this change even more efficient.
| const scrollCheck: boolean = window.scrollY > 100; | ||
| if (scrollCheck !== scroll) { | ||
| setScroll(scrollCheck); | ||
| } |
There was a problem hiding this comment.
The useEffect hook for this component has scroll in its dependency array (on line 37), causing the event listener to be re-attached every time the scroll state changes. This is inefficient and is caused by the dependency on scroll within this if condition.
To improve this, you can remove the conditional check and call setScroll directly. React is already optimized to avoid re-renders if the state value is the same. This change will allow you to remove scroll from the useEffect dependency array (changing it to []), ensuring the listener is attached only once.
The implementation in components/elements/BackToTop.tsx is a good example of this pattern.
| const scrollCheck: boolean = window.scrollY > 100; | |
| if (scrollCheck !== scroll) { | |
| setScroll(scrollCheck); | |
| } | |
| setScroll(window.scrollY > 100); |
| const scrollCheck: boolean = window.scrollY > 100; | ||
| if (scrollCheck !== scroll) { | ||
| setScroll(scrollCheck); | ||
| } |
There was a problem hiding this comment.
Similar to DynamicHeaderWrapper.tsx, the useEffect hook has scroll in its dependency array (on line 102), which is inefficient as it causes the event listener to be re-attached on every scroll state change. This is caused by the if (scrollCheck !== scroll) check.
To optimize this, you can remove the if check and let React handle state update optimizations. This will allow you to use an empty dependency array [] for the useEffect, ensuring the listener is attached only once. After applying the suggestion below, please also change the dependency array on line 102 from [scroll] to [].
| const scrollCheck: boolean = window.scrollY > 100; | |
| if (scrollCheck !== scroll) { | |
| setScroll(scrollCheck); | |
| } | |
| setScroll(window.scrollY > 100); |
![coderabbitai[bot]](https://avatars.githubusercontent.com/in/347564?s=60&v=4){kind=small}
There was a problem hiding this comment.
Caution
Some comments are outside the diff and can’t be posted inline due to platform limitations.
⚠️ Outside diff range comments (1)
components/layout/Layout.tsx (1)
80-102:⚠️ Potential issue | 🟠 Major
AOS.init()is unintentionally re-running on scroll state flips.The effect depends on
[scroll](line 102) but callssetScroll()inside the scroll handler (lines 88–89), creating a dependency cycle. Each time the scroll threshold flips, the effect re-executes, reinitializing AOS and rebinding the listener. Split into two effects: one forAOS.init()with an empty dependency array (runs once), and one for the scroll listener with an empty dependency array using functional state update to avoid closure over stalescrollvalues.💡 Proposed fix
- useEffect(() => { - AOS.init(); - const state = { isTicking: false }; - - const handleScroll = (): void => { - if (!state.isTicking) { - window.requestAnimationFrame(() => { - const scrollCheck: boolean = window.scrollY > 100; - if (scrollCheck !== scroll) { - setScroll(scrollCheck); - } - state.isTicking = false; - }); - state.isTicking = true; - } - }; - - document.addEventListener("scroll", handleScroll, { passive: true }); - - return () => { - document.removeEventListener("scroll", handleScroll); - }; - }, [scroll]); + useEffect(() => { + AOS.init(); + }, []); + + useEffect(() => { + const state = { isTicking: false }; + let rafId: number | null = null; + + const handleScroll = (): void => { + if (state.isTicking) return; + state.isTicking = true; + rafId = window.requestAnimationFrame(() => { + const scrollCheck: boolean = window.scrollY > 100; + setScroll((prev) => (prev === scrollCheck ? prev : scrollCheck)); + state.isTicking = false; + }); + }; + + document.addEventListener("scroll", handleScroll, { passive: true }); + return () => { + if (rafId !== null) window.cancelAnimationFrame(rafId); + document.removeEventListener("scroll", handleScroll); + }; + }, []);🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@components/layout/Layout.tsx` around lines 80 - 102, The effect currently calls AOS.init() and registers the scroll listener but lists [scroll] as a dependency, causing AOS.init() and the listener to re-run when setScroll toggles; split into two effects: one effect that calls AOS.init() (call AOS.init in an effect with an empty dependency array so it runs once) and a separate effect that registers document.addEventListener("scroll", handleScroll) with an empty dependency array, refactor handleScroll to use a functional update to setScroll(prev => newValue) or read window.scrollY inside the RAF and compare against prev via the functional setter to avoid closing over stale scroll values, and ensure you still remove the listener in the cleanup.
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Outside diff comments:
In `@components/layout/Layout.tsx`:
- Around line 80-102: The effect currently calls AOS.init() and registers the
scroll listener but lists [scroll] as a dependency, causing AOS.init() and the
listener to re-run when setScroll toggles; split into two effects: one effect
that calls AOS.init() (call AOS.init in an effect with an empty dependency array
so it runs once) and a separate effect that registers
document.addEventListener("scroll", handleScroll) with an empty dependency
array, refactor handleScroll to use a functional update to setScroll(prev =>
newValue) or read window.scrollY inside the RAF and compare against prev via the
functional setter to avoid closing over stale scroll values, and ensure you
still remove the listener in the cleanup.
ℹ️ Review info
⚙️ Run configuration
Configuration used: Organization UI
Review profile: CHILL
Plan: Pro
Run ID: 038794b0-5a09-4a3e-883c-5f6425a9641d
📒 Files selected for processing (6)
.jules/bolt.md__tests__/components/layout/DynamicHeaderWrapper.test.tsx__tests__/components/layout/Layout.test.tsxcomponents/elements/BackToTop.tsxcomponents/layout/DynamicHeaderWrapper.tsxcomponents/layout/Layout.tsx
1 participant
💡 What: Throttled scroll event listeners using
requestAnimationFrameand added{ passive: true }options inLayout,DynamicHeaderWrapper, andBackToTopcomponents.🎯 Why: Scroll events fire at a very high rate (often 60+ times per second). Updating React state synchronously inside these handlers can lead to main-thread blocking, layout thrashing, and "janky" scrolling.
📊 Impact: Significantly reduces main-thread blocking during scrolling. By deferring state updates to the next animation frame, the browser can maintain a smooth 60fps frame rate while scrolling.
🔬 Measurement: Verify that the header shrinks on scroll and the "Back to top" button appears correctly without lag. Test suites have been updated to mock
requestAnimationFrameand ensure functionality remains intact.PR created automatically by Jules for task 16782550511564095932 started by @anyulled
Summary by CodeRabbit
Documentation
Performance