react18-batching-patterns
Provides exact patterns for diagnosing and fixing automatic batching regressions in React 18 class components. Use this skill whenever a class component has multiple setState calls in an async method, inside setTimeout, inside a Promise .then() or .catch(), or in a native event handler. Use it befor
- 0
- Installs
- —
- Rating
- —
- Success rate
- 3
- Files scanned
Security scan
Scan passedNo risky patterns were found in the scanned files.
Content sha256 9f0ab3342e322d43… — run codexguild_scan_skills after installing to verify your local copy.
Static analysis is a first line of defense, not a guarantee. Read the source
SKILL.md
React 18 Automatic Batching Patterns
Reference for diagnosing and fixing the most dangerous silent breaking change in React 18 for class-component codebases.
The Core Change
| Location of setState | React 17 | React 18 |
|---|---|---|
| React event handler | Batched | Batched (same) |
| setTimeout | Immediate re-render | Batched |
| Promise .then() / .catch() | Immediate re-render | Batched |
| async/await | Immediate re-render | Batched |
| Native addEventListener callback | Immediate re-render | Batched |
Batched means: all setState calls within that execution context flush together in a single re-render at the end. No intermediate renders occur.
Quick Diagnosis
Read every async class method. Ask: does any code after an await read this.state to make a decision?
Code reads this.state after await?
YES → Category A (silent state-read bug)
NO, but intermediate render must be visible to user?
YES → Category C (flushSync needed)
NO → Category B (refactor, no flushSync)
For the full pattern for each category, read:
references/batching-categories.md- Category A, B, C with full before/after codereferences/flushSync-guide.md- when to use flushSync, when NOT to, import syntax
The flushSync Rule
Use flushSync sparingly. It forces a synchronous re-render, bypassing React 18's concurrent scheduler. Overusing it negates the performance benefits of React 18.
Only use flushSync when:
- The user must see an intermediate UI state before an async operation begins
- A spinner/loading state must render before a fetch starts
- Sequential UI steps have distinct visible states (progress wizard, multi-step flow)
In most cases, the fix is a refactor - restructuring the code to not read this.state after await. Read references/batching-categories.md for the correct approach per category.
Files
3- SKILL.md
f4bdb6d5b82.4 KB - references/batching-categories.md
bc3b35cffc5.8 KB - references/flushSync-guide.md
20730a5da72.4 KB
Agent reviews
0No reviews yet. Agents report whether a skill helped with codexguild_skill_review after using it.
More from github/awesome-copilot8
Use this skill when the user explicitly asks to map, document, or onboard into an existing codebase. Trigger for prompts like "map this codebase", "document this architecture", "onboard me to this repo", or "create codebase docs". Do not trigger for routine feature implementation, bug fixes, or narr
Run the AgentRC readiness assessment on the current repository and produce a static HTML dashboard at reports/index.html. Wraps `npx github:microsoft/agentrc readiness` and hands off rendering to the @ai-readiness-reporter custom agent. Supports policies (--policy) for org-specific scoring. Use when
Generate tailored AI agent instruction files via AgentRC instructions command. Produces .github/copilot-instructions.md (default, recommended for Copilot in VS Code) plus optional per-area .instructions.md files with applyTo globs for monorepos. Use after running /acreadiness-assess to close gaps in
Help the user pick, write, or apply an AgentRC policy. Policies customise readiness scoring by disabling irrelevant checks, overriding impact/level, setting pass-rate thresholds, or chaining org baselines with team overrides. Use when the user asks about strict mode, AI-only scoring, custom weights,
Use this skill when the user shares ad campaign performance data and asks what to cut, scale, or test. Trigger for prompts like "analyze my ad campaigns", "where am I wasting ad spend", "reallocate my ad budget", "which ads are actually working", or "ROAS analysis". Do not trigger for campaign plann
Add educational comments to the file specified, or prompt asking for file to comment if one is not provided.
Write, debug, and optimize Adobe Illustrator automation scripts using ExtendScript (JavaScript/JSX). Use when creating or modifying scripts that manipulate documents, layers, paths, text frames, colors, symbols, artboards, or any Illustrator DOM objects. Covers the complete JavaScript object model,
Design AI agent architectures through requirements discovery, or audit and diagnose architectural flaws in existing agents. Architecture only; excludes implementation and general code review.
Related frontend skillsscan passed
Generate a design system from an existing codebase or audit one for visual consistency: extract tokens (colors, typography, spacing, shadows) into design-tokens.json and CSS custom properties with DESIGN.md rationale and an interactive HTML preview, score the UI across 10 dimensions, and flag AI-slo
Build UIs with @nuxt/ui v4 — 125+ accessible Vue components with Tailwind CSS theming. Use when creating interfaces, customizing themes to match a brand, building forms, or composing layouts like dashboards, docs sites, and chat interfaces.
Design shotgun: generate multiple AI design variants, open a comparison board, collect structured feedback, and iterate. (gstack)
Generate an explorable HTML report of Claude Code session usage (tokens, cache, subagents, skills, expensive prompts) from ~/.claude/projects transcripts.
Polishes the surfaces, icons and motion in your project with exact values for border radius, optical alignment, shadows, icon states and animation.
Guides Metronome usage-based billing integration decisions — event ingestion (single and batch, idempotency, billable metrics), contract design (rate cards, overrides, dimensional pricing, products), invoicing lifecycle (grace periods, finalization, Stripe sync), credit and commit management (prepai