Files
infinite-canvas/.agents/skills/vercel-react-best-practices/rules/js-tosorted-immutable.md
T
HouYunFei fb79a15508 docs(vercel-react-best-practices): 添加 Vercel React 最佳实践规则文档
- 添加 sections 定义文件,包含性能优化各领域分类
- 添加规则模板文件,规范文档结构和标签定义
- 添加异步操作优化规则,包括防止瀑布流、并行化、延迟等待等
- 添加包大小优化规则,包括避免桶式导入、动态导入、预加载等
- 添加服务端性能优化规则,包括 API 路
2026-05-21 15:22:11 +08:00

1.7 KiB

title, impact, impactDescription, tags
title impact impactDescription tags
Use toSorted() Instead of sort() for Immutability MEDIUM-HIGH prevents mutation bugs in React state javascript, arrays, immutability, react, state, mutation

Use toSorted() Instead of sort() for Immutability

.sort() mutates the array in place, which can cause bugs with React state and props. Use .toSorted() to create a new sorted array without mutation.

Incorrect (mutates original array):

function UserList({ users }: { users: User[] }) {
  // Mutates the users prop array!
  const sorted = useMemo(
    () => users.sort((a, b) => a.name.localeCompare(b.name)),
    [users]
  )
  return <div>{sorted.map(renderUser)}</div>
}

Correct (creates new array):

function UserList({ users }: { users: User[] }) {
  // Creates new sorted array, original unchanged
  const sorted = useMemo(
    () => users.toSorted((a, b) => a.name.localeCompare(b.name)),
    [users]
  )
  return <div>{sorted.map(renderUser)}</div>
}

Why this matters in React:

  1. Props/state mutations break React's immutability model - React expects props and state to be treated as read-only
  2. Causes stale closure bugs - Mutating arrays inside closures (callbacks, effects) can lead to unexpected behavior

Browser support (fallback for older browsers):

.toSorted() is available in all modern browsers (Chrome 110+, Safari 16+, Firefox 115+, Node.js 20+). For older environments, use spread operator:

// Fallback for older browsers
const sorted = [...items].sort((a, b) => a.value - b.value)

Other immutable array methods:

  • .toSorted() - immutable sort
  • .toReversed() - immutable reverse
  • .toSpliced() - immutable splice
  • .with() - immutable element replacement