feat(ui): add delay support to Spin

docs/components/spin.md

@@ -7,12 +7,14 @@
 <LivePlayground :code="`
 () => {
   return (
-    <Space direction='vertical' size={12}>
-      <Spin tip='加载中...' />
-      <Spin spinning={true}>
-        <Card title='卡片标题'>被 Spin 包裹的内容区域</Card>
+    <div className='flex flex-col gap-4'>
+      <Spin tip='加载中...' delay={200} />
+      <Spin spinning={true} delay={200}>
+        <div className='rounded-lg border border-slate-200 bg-white p-4 text-sm text-slate-700 shadow-sm dark:border-slate-700 dark:bg-slate-900 dark:text-slate-200'>
+          被 Spin 包裹的内容区域
+        </div>
       </Spin>
-    </Space>
+    </div>
   )
 }
 `" />
@@ -21,13 +23,16 @@
 
 Spin 在加载中时会渲染为 `role="status"` 的 polite live region。纯视觉旋转图形会从辅助技术中隐藏；当包裹子元素时，外层容器会根据 `spinning` 同步 `aria-busy`。当页面中存在多个加载状态时，建议通过 `tip`、`aria-label` 或 `aria-labelledby` 提供可区分名称。
 
+当设置 `delay` 时，Spin 会延迟显示视觉 spinner 和 `status` live region；如果 `spinning` 在延迟结束前变为 `false`，则不会显示 spinner。包裹子元素时，`aria-busy` 仍会立即反映真实加载状态。
+
 ## API
 
 | 属性            | 说明                     | 类型                               | 默认值                   |
 | --------------- | ------------------------ | ---------------------------------- | ------------------------ |
 | spinning        | 是否加载中               | `boolean`                          | `true`                   |
 | size            | 尺寸                     | `'sm' \| 'md' \| 'lg'`             | `'md'`                   |
 | tip             | 提示文字                 | `ReactNode`                        | -                        |
+| delay           | 延迟显示加载状态的毫秒数 | `number`                           | `0`                      |
 | aria-label      | 加载状态可访问名称       | `string`                           | `tip` 文本或 `'Loading'` |
 | aria-labelledby | 使用外部标签命名加载状态 | `string`                           | -                        |
 | aria-live       | 加载状态通知优先级       | `'off' \| 'polite' \| 'assertive'` | `'polite'`               |

packages/ui/src/components/feedback/Spin/Spin.test.tsx

@@ -1,8 +1,13 @@
-import { render, screen } from '@testing-library/react'
-import { describe, expect, it } from 'vitest'
+import { act, cleanup, render, screen } from '@testing-library/react'
+import { afterEach, describe, expect, it, vi } from 'vitest'
 
 import { Spin } from './Spin'
 
+afterEach(() => {
+  cleanup()
+  vi.useRealTimers()
+})
+
 describe('Spin', () => {
   it('announces standalone loading state as a polite status', () => {
     render(<Spin />)
@@ -20,6 +25,38 @@ describe('Spin', () => {
     expect(screen.getByText('Loading invoices')).toBeInTheDocument()
   })
 
+  it('delays the standalone loading status when delay is set', () => {
+    vi.useFakeTimers()
+
+    render(<Spin delay={200} />)
+
+    expect(screen.queryByRole('status')).not.toBeInTheDocument()
+
+    act(() => {
+      vi.advanceTimersByTime(199)
+    })
+    expect(screen.queryByRole('status')).not.toBeInTheDocument()
+
+    act(() => {
+      vi.advanceTimersByTime(1)
+    })
+    expect(screen.getByRole('status', { name: 'Loading' })).toBeInTheDocument()
+  })
+
+  it('does not show a delayed spinner when spinning stops before delay ends', () => {
+    vi.useFakeTimers()
+
+    const { rerender } = render(<Spin delay={200} />)
+
+    rerender(<Spin spinning={false} delay={200} />)
+
+    act(() => {
+      vi.advanceTimersByTime(200)
+    })
+
+    expect(screen.queryByRole('status')).not.toBeInTheDocument()
+  })
+
   it('marks wrapped content busy while the overlay is spinning', () => {
     render(
       <Spin spinning tip="Refreshing data">
@@ -33,6 +70,26 @@ describe('Spin', () => {
     expect(screen.getByRole('status', { name: 'Refreshing data' })).toBeInTheDocument()
   })
 
+  it('marks wrapped content busy while a delayed overlay is pending', () => {
+    vi.useFakeTimers()
+
+    render(
+      <Spin spinning delay={200} tip="Refreshing data">
+        <section aria-label="Report panel">Report content</section>
+      </Spin>,
+    )
+
+    const wrapper = screen.getByText('Report content').parentElement
+
+    expect(wrapper).toHaveAttribute('aria-busy', 'true')
+    expect(screen.queryByRole('status')).not.toBeInTheDocument()
+
+    act(() => {
+      vi.advanceTimersByTime(200)
+    })
+    expect(screen.getByRole('status', { name: 'Refreshing data' })).toBeInTheDocument()
+  })
+
   it('marks wrapped content not busy and hides status when spinning stops', () => {
     render(
       <Spin spinning={false}>
@@ -45,4 +102,4 @@ describe('Spin', () => {
     expect(wrapper).toHaveAttribute('aria-busy', 'false')
     expect(screen.queryByRole('status')).not.toBeInTheDocument()
   })
-})
+})

packages/ui/src/components/feedback/Spin/Spin.tsx

@@ -1,10 +1,11 @@
-import { forwardRef, type HTMLAttributes, type ReactNode } from 'react'
+import { forwardRef, useEffect, useState, type HTMLAttributes, type ReactNode } from 'react'
 import { cn } from '../../../utils/cn'
 
 export interface SpinProps extends HTMLAttributes<HTMLDivElement> {
   spinning?: boolean
   size?: 'sm' | 'md' | 'lg'
   tip?: ReactNode
+  delay?: number
 }
 
 export const Spin = forwardRef<HTMLDivElement, SpinProps>(function Spin(
@@ -13,6 +14,7 @@ export const Spin = forwardRef<HTMLDivElement, SpinProps>(function Spin(
     spinning = true,
     size = 'md',
     tip,
+    delay = 0,
     children,
     'aria-label': ariaLabel,
     'aria-labelledby': ariaLabelledBy,
@@ -21,9 +23,31 @@ export const Spin = forwardRef<HTMLDivElement, SpinProps>(function Spin(
   },
   ref,
 ) {
+  const [showSpinner, setShowSpinner] = useState(() => spinning && delay <= 0)
   const accessibleLabel =
     ariaLabel ?? (ariaLabelledBy ? undefined : typeof tip === 'string' ? tip : 'Loading')
 
+  useEffect(() => {
+    if (!spinning) {
+      setShowSpinner(false)
+      return
+    }
+
+    if (delay <= 0) {
+      setShowSpinner(true)
+      return
+    }
+
+    setShowSpinner(false)
+    const timer = window.setTimeout(() => {
+      setShowSpinner(true)
+    }, delay)
+
+    return () => {
+      window.clearTimeout(timer)
+    }
+  }, [delay, spinning])
+
   const spinner = (
     <div
       className="flex flex-col items-center gap-2"
@@ -48,7 +72,7 @@ export const Spin = forwardRef<HTMLDivElement, SpinProps>(function Spin(
   )
 
   if (!children) {
-    return spinning ? (
+    return showSpinner ? (
       <div
         ref={ref}
         className={cn('inline-flex items-center justify-center', className)}
@@ -62,11 +86,11 @@ export const Spin = forwardRef<HTMLDivElement, SpinProps>(function Spin(
   return (
     <div ref={ref} className={cn('relative', className)} {...props} aria-busy={spinning}>
       {children}
-      {spinning ? (
+      {showSpinner ? (
         <div className="absolute inset-0 flex items-center justify-center rounded bg-white/60 dark:bg-slate-900/60">
           {spinner}
         </div>
       ) : null}
     </div>
   )
-})
+})