auto-animate

AutoAnimate - Error Prevention Guide

Package: @formkit/[email protected] (Sept 2025) Frameworks: React, Vue, Solid, Svelte, Preact Last Updated: 2025-11-22

---

SSR-Safe Pattern (Critical for Cloudflare Workers/Next.js)

// Use client-only import to prevent SSR errors
import { useState, useEffect } from "react";

export function useAutoAnimateSafe<T extends HTMLElement>() {
  const [parent, setParent] = useState<T | null>(null);

  useEffect(() => {
    if (typeof window !== "undefined" && parent) {
      import("@formkit/auto-animate").then(({ default: autoAnimate }) => {
        autoAnimate(parent);
      });
    }
  }, [parent]);

  return [parent, setParent] as const;
}

Why this matters: Prevents Issue #1 (SSR/Next.js import errors). AutoAnimate uses DOM APIs not available on server.

---

Known Issues Prevention (10 Documented Errors)

This skill prevents 10+ documented issues:

Issue #1: SSR/Next.js Import Errors

Error: "Can't import the named export 'useEffect' from non EcmaScript module" Source: https://github.com/formkit/auto-animate/issues/55 Why It Happens: AutoAnimate uses DOM APIs not available on server Prevention: Use dynamic imports (see templates/vite-ssr-safe.tsx)

Issue #2: Conditional Parent Rendering

Error: Animations don't work when parent is conditional Source: https://github.com/formkit/auto-animate/issues/8 Why It Happens: Ref can't attach to non-existent element Prevention:

// ❌ Wrong
{showList && <ul ref={parent}>...</ul>}

// ✅ Correct
<ul ref={parent}>{showList && items.map(...)}</ul>

Issue #3: Missing Unique Keys

Error: Items don't animate correctly or flash Source: Official docs Why It Happens: React can't track which items changed Prevention: Always use unique, stable keys (key={item.id})

Issue #4: Flexbox Width Issues

Error: Elements snap to width instead of animating smoothly Source: Official docs Why It Happens: flex-grow: 1 waits for surrounding content Prevention: Use explicit width instead of flex-grow for animated elements

Issue #5: Table Row Display Issues

Error: Table structure breaks when removing rows Source: https://github.com/formkit/auto-animate/issues/7 Why It Happens: Display: table-row conflicts with animations Prevention: Apply to <tbody> instead of individual rows, or use div-based layouts

Issue #6: Jest Testing Errors

Error: "Cannot find module '@formkit/auto-animate/react'" Source: https://github.com/formkit/auto-animate/issues/29 Why It Happens: Jest doesn't resolve ESM exports correctly Prevention: Configure moduleNameMapper in jest.config.js

Issue #7: esbuild Compatibility

Error: "Path '.' not exported by package" Source: https://github.com/formkit/auto-animate/issues/36 Why It Happens: ESM/CommonJS condition mismatch Prevention: Configure esbuild to handle ESM modules properly

Issue #8: CSS Position Side Effects

Error: Layout breaks after adding AutoAnimate Source: Official docs Why It Happens: Parent automatically gets position: relative Prevention: Account for position change in CSS or set explicitly

Issue #9: Vue/Nuxt Registration Errors

Error: "Failed to resolve directive: auto-animate" Source: https://github.com/formkit/auto-animate/issues/43 Why It Happens: Plugin not registered correctly Prevention: Proper plugin setup in Vue/Nuxt config (see references/)

Issue #10: Angular ESM Issues

Error: Build fails with "ESM-only package" Source: https://github.com/formkit/auto-animate/issues/72 Why It Happens: CommonJS build environment Prevention: Configure ng-packagr for Angular Package Format

---

Critical Rules (Error Prevention)

Always Do

✅ Use unique, stable keys - key={item.id} not key={index} ✅ Keep parent in DOM - Parent ref element always rendered ✅ Client-only for SSR - Dynamic import for server environments ✅ Respect accessibility - Keep disrespectUserMotionPreference: false ✅ Test with motion disabled - Verify UI works without animations ✅ Use explicit width - Avoid flex-grow on animated elements ✅ Apply to tbody for tables - Not individual rows

Never Do

❌ Conditional parent - {show && <ul ref={parent}>} ❌ Index as key - key={index} breaks animations ❌ Ignore SSR - Will break in Cloudflare Workers/Next.js ❌ Force animations - disrespectUserMotionPreference: true breaks accessibility ❌ Animate tables directly - Use tbody or div-based layout ❌ Skip unique keys - Required for proper animation ❌ Complex animations - Use Motion instead

Note: AutoAnimate respects prefers-reduced-motion automatically (never disable this).

---

Package Versions

Latest: @formkit/[email protected] (Sept 5, 2025)

{
  "dependencies": {
    "@formkit/auto-animate": "^0.9.0"
  }
}

Framework Compatibility: React 18+, Vue 3+, Solid, Svelte, Preact

---

Official Documentation

• Official Site: https://auto-animate.formkit.com
• GitHub: https://github.com/formkit/auto-animate
• npm: https://www.npmjs.com/package/@formkit/auto-animate
• React Docs: https://auto-animate.formkit.com/react

---

Templates & References

See bundled resources:

• templates/ - Copy-paste examples (SSR-safe, accordion, toast, forms)
• references/ - CSS conflicts, SSR patterns, library comparisons