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Merged
kylemac merged 1 commit into from
Jun 10, 2026
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docs(swingset): document Collapsible headless primitive #8809

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2 changes: 2 additions & 0 deletions .changeset/document-headless-collapsible.md
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Open in desktop
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,2 @@
---
---
2 changes: 2 additions & 0 deletions packages/swingset/next.config.mjs
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Original file line numberDiff line numberDiff line change
Expand Up@@ -29,6 +29,8 @@ const nextConfig = {
},
webpack(config) {
config.resolve.alias['@clerk/ui/mosaic'] = resolve(__dirname, '../ui/src/mosaic');
// Consume @clerk/headless primitives from source (no dist build needed), mirroring Mosaic.
config.resolve.alias['@clerk/headless'] = resolve(__dirname, '../headless/src/primitives');
return config;
},
};
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1 change: 1 addition & 0 deletions packages/swingset/package.json
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Expand Up@@ -11,6 +11,7 @@
},
"dependencies": {
"@base-ui/react": "^1.5.0",
"@clerk/headless": "workspace:*",
"@clerk/ui": "workspace:*",
"@emotion/react": "^11.11.1",
"@tailwindcss/typography": "^0.5.19",
Expand Down
16 changes: 9 additions & 7 deletions packages/swingset/src/app/layout.tsx
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Expand Up@@ -22,13 +22,15 @@ export default function RootLayout({ children }: { children: React.ReactNode })
suppressHydrationWarning
className={cn('font-sans', geist.variable)}
>
{process.env.NODE_ENV === 'development' && (
<Script
src='//unpkg.com/react-grab/dist/index.global.js'
crossOrigin='anonymous'
strategy='beforeInteractive'
/>
)}
<head>
{process.env.NODE_ENV === 'development' && (
<Script
src='//unpkg.com/react-grab/dist/index.global.js'
crossOrigin='anonymous'
strategy='beforeInteractive'
/>
)}
</head>
<body className='antialiased'>
<ThemeProvider>
<ClientRoot>{children}</ClientRoot>
Expand Down
1 change: 1 addition & 0 deletions packages/swingset/src/components/DocsViewer.tsx
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Original file line numberDiff line numberDiff line change
Expand Up@@ -4,6 +4,7 @@ import dynamic from 'next/dynamic';

const docModules: Record<string, React.ComponentType> = {
button: dynamic(() => import('../stories/button.mdx')),
collapsible: dynamic(() => import('../stories/collapsible.mdx')),
};

interface DocsViewerProps {
Expand Down
6 changes: 5 additions & 1 deletion packages/swingset/src/components/StoryCanvas.tsx
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Expand Up@@ -32,7 +32,11 @@ export function StoryCanvas({ componentSlug, storySlug }: StoryCanvasProps) {
const nextKnobs = generateKnobs(found.mod.meta);
setKnobs(nextKnobs);
setKnobValues(initKnobValues(nextKnobs));
}, [found, componentSlug, storySlug]);
// `found` is derived synchronously from the slugs each render and is a fresh
// object every time, so depending on it would re-run this effect on every
// render. Depend on the stable slug strings instead.
// eslint-disable-next-line react-hooks/exhaustive-deps
}, [componentSlug, storySlug]);

if (!found) {
return <div className='text-muted-foreground p-8 text-sm'>Story not found.</div>;
Expand Down
9 changes: 8 additions & 1 deletion packages/swingset/src/lib/registry.ts
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@@ -1,11 +1,18 @@
// Import stories explicitly to control order and avoid type casting through unknown.
import { Disabled, meta as buttonMeta, Primary, Sizes } from '../stories/button.stories';
import { meta as collapsibleMeta } from '../stories/collapsible.stories';
import { toSlug } from './slug';
import type { StoryModule } from './types';

const buttonModule: StoryModule = { meta: buttonMeta, Primary, Sizes, Disabled };

export const registry: StoryModule[] = [buttonModule];
// Headless primitives are documented as overview-only: the registry entry carries
// just `meta` (no story functions), so the sidebar shows a single "Overview" link and
// no interactive knob canvas. The overview's live demos come from `<Story>` embeds in
// the MDX, which import the stories module directly (not through this registry).
const collapsibleModule: StoryModule = { meta: collapsibleMeta };

export const registry: StoryModule[] = [buttonModule, collapsibleModule];

export interface RegistryEntry {
mod: StoryModule;
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2 changes: 1 addition & 1 deletion packages/swingset/src/stories/button.mdx
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Expand Up@@ -35,7 +35,7 @@ import { Button } from '@clerk/ui/mosaic/components/button';
size='md'
>
Click me
</Button>;
</Button>
```

## Props
Expand Down
94 changes: 94 additions & 0 deletions packages/swingset/src/stories/collapsible.mdx
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@@ -0,0 +1,94 @@
import * as CollapsibleStories from './collapsible.stories';

# Collapsible

A single show/hide panel toggled by a button, from `@clerk/headless`. It is a
**headless** primitive: it supplies behavior, state, ARIA wiring, and the
expand/collapse animation lifecycle, but ships **no styles** — you bring your own
CSS by targeting the `data-cl-*` attributes each part emits.

## Example

The demo below is intentionally unstyled — it renders the raw primitive so you can see
its behavior and ARIA wiring. Click the trigger to expand and collapse.

<Story
name='Default'
storyModule={CollapsibleStories}
/>

## Usage

```tsx
import { Collapsible } from '@clerk/headless/collapsible';

<Collapsible.Root>
<Collapsible.Trigger>Toggle</Collapsible.Trigger>
<Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

### Controlled

```tsx
const [open, setOpen] = useState(false);

<Collapsible.Root
open={open}
onOpenChange={setOpen}
>
<Collapsible.Trigger>Toggle</Collapsible.Trigger>
<Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

## Parts

| Part | Default Element | Description |
| --------------------- | --------------- | ---------------------------------- |
| `Collapsible.Root` | `<div>` | Root wrapper, provides context |
| `Collapsible.Trigger` | `<button>` | Clickable toggle that opens/closes |
| `Collapsible.Panel` | `<div>` | Collapsible content area |

All parts accept a `render` prop for polymorphic rendering and standard HTML
attributes for their default element.

## Props

### `Collapsible.Root`

| Prop | Type | Default | Description |
| ------------------------- | ------------------------------------ | ------------------ | ---------------------------------- |
| <code>open</code> | <code>boolean</code> | — | Controlled open state |
| <code>defaultOpen</code> | <code>boolean</code> | <code>false</code> | Initial open state (uncontrolled) |
| <code>onOpenChange</code> | <code>(open: boolean) => void</code> | — | Called when open state changes |
| <code>disabled</code> | <code>boolean</code> | <code>false</code> | Prevents the trigger from toggling |

`Collapsible.Trigger` and `Collapsible.Panel` take no additional props beyond
standard HTML attributes for their default element.

## Styling

Each part emits `data-cl-*` attributes you can target with any CSS solution:

| Attribute | Applies To | Description |
| ------------------ | -------------------- | -------------------------------- |
| `data-cl-slot` | All parts | Part identifier |
| `data-cl-open` | Root, Trigger, Panel | Present when the panel is open |
| `data-cl-closed` | Root, Trigger, Panel | Present when the panel is closed |
| `data-cl-disabled` | Root, Trigger | Present when disabled |

`Collapsible.Panel` also exposes `--collapsible-panel-height` /
`--collapsible-panel-width` (its measured dimensions) for height/width-based
animations:

```css
[data-cl-slot='collapsible-panel'] {
overflow: hidden;
height: var(--collapsible-panel-height);
transition: height 200ms ease;
}
[data-cl-slot='collapsible-panel'][data-cl-closed] {
height: 0;
}
```
27 changes: 27 additions & 0 deletions packages/swingset/src/stories/collapsible.stories.tsx
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@@ -0,0 +1,27 @@
import { Collapsible } from '@clerk/headless/collapsible';

import type { StoryMeta } from '@/lib/types';

// Headless primitives ship no styles. This single demo renders the primitive raw —
// unstyled — so it faithfully reflects what `@clerk/headless` provides: behavior, state,
// and ARIA wiring via the `data-cl-*` attributes each part emits, with zero appearance.
// It is embedded once into the overview via `<Story>` in the MDX (the one thing prose
// can't convey: that it actually expands/collapses). There is no interactive knob canvas
// for headless primitives.

export const meta: StoryMeta = {
group: 'Primitives',
title: 'Collapsible',
};

export function Default() {
return (
<Collapsible.Root>
<Collapsible.Trigger>What is a headless component?</Collapsible.Trigger>
<Collapsible.Panel>
A headless component provides behavior, state management, and accessibility without imposing any styles — you
bring your own CSS via the <code>data-cl-slot</code> attributes it emits.
</Collapsible.Panel>
</Collapsible.Root>
);
}
3 changes: 2 additions & 1 deletion packages/swingset/tsconfig.json
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Original file line numberDiff line numberDiff line change
Expand Up@@ -13,7 +13,8 @@
"paths": {
"@/*": ["./src/*"],
"@clerk/ui/mosaic": ["../ui/src/mosaic"],
"@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"]
"@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"],
"@clerk/headless/*": ["../headless/src/primitives/*"]
},
"plugins": [
{
Expand Down
3 changes: 3 additions & 0 deletions pnpm-lock.yaml
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Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.

10 changes: 10 additions & 0 deletions prettier.config.mjs
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Original file line numberDiff line numberDiff line change
Expand Up@@ -9,4 +9,14 @@ export default {
singleQuote: true,
tabWidth: 2,
trailingComma: 'all',
overrides: [
{
// Leave fenced code samples in MDX docs exactly as authored. Without this,
// `semi: true` reformats the embedded code and re-adds trailing semicolons to
// JSX usage examples (e.g. `</Collapsible.Root>;`). Markdown prose and tables
// are still formatted as normal.
files: '*.mdx',
options: { embeddedLanguageFormatting: 'off' },
},
],
};
Loading
, 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
 blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
btn.onclick = function() {
navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
docs(swingset): document Collapsible headless primitive by kylemac · Pull Request #8809 · clerk/javascript · GitHub
Skip to content
docs(swingset): document Collapsible headless primitive#8809

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to your account

 Merged

kylemac
merged 1 commit into

from

Jun 10, 2026
 Merged


docs(swingset): document Collapsible headless primitive
#8809
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2 changes: 2 additions & 0 deletions
.changeset/document-headless-collapsible.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,2 @@
---
---

2 changes: 2 additions & 0 deletions
packages/swingset/next.config.mjs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -29,6 +29,8 @@ const nextConfig = {
 },
 webpack(config) {
 config.resolve.alias['@clerk/ui/mosaic'] = resolve(__dirname, '../ui/src/mosaic');
 // Consume @clerk/headless primitives from source (no dist build needed), mirroring Mosaic.
 config.resolve.alias['@clerk/headless'] = resolve(__dirname, '../headless/src/primitives');
 return config;
 },
};
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/package.json

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@
 },
 "dependencies": {
 "@base-ui/react": "^1.5.0",
 "@clerk/headless": "workspace:*",
 "@clerk/ui": "workspace:*",
 "@emotion/react": "^11.11.1",
 "@tailwindcss/typography": "^0.5.19",
Expand Down

16 changes: 9 additions & 7 deletions
packages/swingset/src/app/layout.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,13 +22,15 @@ export default function RootLayout({ children }: { children: React.ReactNode })
 suppressHydrationWarning
 className={cn('font-sans', geist.variable)}
 >
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 <head>
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 </head>
 <body className='antialiased'>
 <ThemeProvider>
 <ClientRoot>{children}</ClientRoot>
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/src/components/DocsViewer.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4,6 +4,7 @@ import dynamic from 'next/dynamic';

const docModules: Record<string, React.ComponentType> = {
 button: dynamic(() => import('../stories/button.mdx')),
 collapsible: dynamic(() => import('../stories/collapsible.mdx')),
};

interface DocsViewerProps {
Expand Down

6 changes: 5 additions & 1 deletion
packages/swingset/src/components/StoryCanvas.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -32,7 +32,11 @@ export function StoryCanvas({ componentSlug, storySlug }: StoryCanvasProps) {
 const nextKnobs = generateKnobs(found.mod.meta);
 setKnobs(nextKnobs);
 setKnobValues(initKnobValues(nextKnobs));
 }, [found, componentSlug, storySlug]);
 // `found` is derived synchronously from the slugs each render and is a fresh
 // object every time, so depending on it would re-run this effect on every
 // render. Depend on the stable slug strings instead.
 // eslint-disable-next-line react-hooks/exhaustive-deps
 }, [componentSlug, storySlug]);

 if (!found) {
 return <div className='text-muted-foreground p-8 text-sm'>Story not found.</div>;
Expand Down

9 changes: 8 additions & 1 deletion
packages/swingset/src/lib/registry.ts

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Original file line numberDiff line numberDiff line change
@@ -1,11 +1,18 @@
// Import stories explicitly to control order and avoid type casting through unknown.
import { Disabled, meta as buttonMeta, Primary, Sizes } from '../stories/button.stories';
import { meta as collapsibleMeta } from '../stories/collapsible.stories';
import { toSlug } from './slug';
import type { StoryModule } from './types';

const buttonModule: StoryModule = { meta: buttonMeta, Primary, Sizes, Disabled };

export const registry: StoryModule[] = [buttonModule];
// Headless primitives are documented as overview-only: the registry entry carries
// just `meta` (no story functions), so the sidebar shows a single "Overview" link and
// no interactive knob canvas. The overview's live demos come from `<Story>` embeds in
// the MDX, which import the stories module directly (not through this registry).
const collapsibleModule: StoryModule = { meta: collapsibleMeta };

export const registry: StoryModule[] = [buttonModule, collapsibleModule];

export interface RegistryEntry {
 mod: StoryModule;
Expand Down

2 changes: 1 addition & 1 deletion
packages/swingset/src/stories/button.mdx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -35,7 +35,7 @@ import { Button } from '@clerk/ui/mosaic/components/button';
 size='md'
>
 Click me
</Button>;
</Button>
```

## Props
Expand Down

94 changes: 94 additions & 0 deletions
packages/swingset/src/stories/collapsible.mdx

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,94 @@
import * as CollapsibleStories from './collapsible.stories';

# Collapsible

A single show/hide panel toggled by a button, from `@clerk/headless`. It is a
**headless** primitive: it supplies behavior, state, ARIA wiring, and the
expand/collapse animation lifecycle, but ships **no styles** — you bring your own
CSS by targeting the `data-cl-*` attributes each part emits.

## Example

The demo below is intentionally unstyled — it renders the raw primitive so you can see
its behavior and ARIA wiring. Click the trigger to expand and collapse.

<Story
 name='Default'
 storyModule={CollapsibleStories}
/>

## Usage

```tsx
import { Collapsible } from '@clerk/headless/collapsible';

<Collapsible.Root>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

### Controlled

```tsx
const [open, setOpen] = useState(false);

<Collapsible.Root
 open={open}
 onOpenChange={setOpen}
>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

## Parts

| Part | Default Element | Description |
| --------------------- | --------------- | ---------------------------------- |
| `Collapsible.Root` | `<div>` | Root wrapper, provides context |
| `Collapsible.Trigger` | `<button>` | Clickable toggle that opens/closes |
| `Collapsible.Panel` | `<div>` | Collapsible content area |

All parts accept a `render` prop for polymorphic rendering and standard HTML
attributes for their default element.

## Props

### `Collapsible.Root`

| Prop | Type | Default | Description |
| ------------------------- | ------------------------------------ | ------------------ | ---------------------------------- |
| <code>open</code> | <code>boolean</code> | — | Controlled open state |
| <code>defaultOpen</code> | <code>boolean</code> | <code>false</code> | Initial open state (uncontrolled) |
| <code>onOpenChange</code> | <code>(open: boolean) => void</code> | — | Called when open state changes |
| <code>disabled</code> | <code>boolean</code> | <code>false</code> | Prevents the trigger from toggling |

`Collapsible.Trigger` and `Collapsible.Panel` take no additional props beyond
standard HTML attributes for their default element.

## Styling

Each part emits `data-cl-*` attributes you can target with any CSS solution:

| Attribute | Applies To | Description |
| ------------------ | -------------------- | -------------------------------- |
| `data-cl-slot` | All parts | Part identifier |
| `data-cl-open` | Root, Trigger, Panel | Present when the panel is open |
| `data-cl-closed` | Root, Trigger, Panel | Present when the panel is closed |
| `data-cl-disabled` | Root, Trigger | Present when disabled |

`Collapsible.Panel` also exposes `--collapsible-panel-height` /
`--collapsible-panel-width` (its measured dimensions) for height/width-based
animations:

```css
[data-cl-slot='collapsible-panel'] {
 overflow: hidden;
 height: var(--collapsible-panel-height);
 transition: height 200ms ease;
}
[data-cl-slot='collapsible-panel'][data-cl-closed] {
 height: 0;
}
```

27 changes: 27 additions & 0 deletions
packages/swingset/src/stories/collapsible.stories.tsx

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,27 @@
import { Collapsible } from '@clerk/headless/collapsible';

import type { StoryMeta } from '@/lib/types';

// Headless primitives ship no styles. This single demo renders the primitive raw —
// unstyled — so it faithfully reflects what `@clerk/headless` provides: behavior, state,
// and ARIA wiring via the `data-cl-*` attributes each part emits, with zero appearance.
// It is embedded once into the overview via `<Story>` in the MDX (the one thing prose
// can't convey: that it actually expands/collapses). There is no interactive knob canvas
// for headless primitives.

export const meta: StoryMeta = {
 group: 'Primitives',
 title: 'Collapsible',
};

export function Default() {
 return (
 <Collapsible.Root>
 <Collapsible.Trigger>What is a headless component?</Collapsible.Trigger>
 <Collapsible.Panel>
 A headless component provides behavior, state management, and accessibility without imposing any styles — you
 bring your own CSS via the <code>data-cl-slot</code> attributes it emits.
 </Collapsible.Panel>
 </Collapsible.Root>
 );
}

3 changes: 2 additions & 1 deletion
packages/swingset/tsconfig.json

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -13,7 +13,8 @@
 "paths": {
 "@/*": ["./src/*"],
 "@clerk/ui/mosaic": ["../ui/src/mosaic"],
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"]
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"],
 "@clerk/headless/*": ["../headless/src/primitives/*"]
 },
 "plugins": [
 {
Expand Down

3 changes: 3 additions & 0 deletions
pnpm-lock.yaml

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Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.


10 changes: 10 additions & 0 deletions
prettier.config.mjs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -9,4 +9,14 @@ export default {
 singleQuote: true,
 tabWidth: 2,
 trailingComma: 'all',
 overrides: [
 {
 // Leave fenced code samples in MDX docs exactly as authored. Without this,
 // `semi: true` reformats the embedded code and re-adds trailing semicolons to
 // JSX usage examples (e.g. `</Collapsible.Root>;`). Markdown prose and tables
 // are still formatted as normal.
 files: '*.mdx',
 options: { embeddedLanguageFormatting: 'off' },
 },
 ],
};
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
.markdown-body img { background: #0d1117; }
.markdown-body blockquote { border-left-color: #8b949e; }
.markdown-body hr { border-color: #30363d; }
';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
docs(swingset): document Collapsible headless primitive by kylemac · Pull Request #8809 · clerk/javascript · GitHub
Skip to content
docs(swingset): document Collapsible headless primitive#8809

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privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

kylemac
merged 1 commit into

from

Jun 10, 2026
 Merged


docs(swingset): document Collapsible headless primitive
#8809
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.changeset/document-headless-collapsible.md

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@@ -0,0 +1,2 @@
---
---

2 changes: 2 additions & 0 deletions
packages/swingset/next.config.mjs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -29,6 +29,8 @@ const nextConfig = {
 },
 webpack(config) {
 config.resolve.alias['@clerk/ui/mosaic'] = resolve(__dirname, '../ui/src/mosaic');
 // Consume @clerk/headless primitives from source (no dist build needed), mirroring Mosaic.
 config.resolve.alias['@clerk/headless'] = resolve(__dirname, '../headless/src/primitives');
 return config;
 },
};
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1 change: 1 addition & 0 deletions
packages/swingset/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@
 },
 "dependencies": {
 "@base-ui/react": "^1.5.0",
 "@clerk/headless": "workspace:*",
 "@clerk/ui": "workspace:*",
 "@emotion/react": "^11.11.1",
 "@tailwindcss/typography": "^0.5.19",
Expand Down

16 changes: 9 additions & 7 deletions
packages/swingset/src/app/layout.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -22,13 +22,15 @@ export default function RootLayout({ children }: { children: React.ReactNode })
 suppressHydrationWarning
 className={cn('font-sans', geist.variable)}
 >
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 <head>
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 </head>
 <body className='antialiased'>
 <ThemeProvider>
 <ClientRoot>{children}</ClientRoot>
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1 change: 1 addition & 0 deletions
packages/swingset/src/components/DocsViewer.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -4,6 +4,7 @@ import dynamic from 'next/dynamic';

const docModules: Record<string, React.ComponentType> = {
 button: dynamic(() => import('../stories/button.mdx')),
 collapsible: dynamic(() => import('../stories/collapsible.mdx')),
};

interface DocsViewerProps {
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6 changes: 5 additions & 1 deletion
packages/swingset/src/components/StoryCanvas.tsx

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Expand Up@@ -32,7 +32,11 @@ export function StoryCanvas({ componentSlug, storySlug }: StoryCanvasProps) {
 const nextKnobs = generateKnobs(found.mod.meta);
 setKnobs(nextKnobs);
 setKnobValues(initKnobValues(nextKnobs));
 }, [found, componentSlug, storySlug]);
 // `found` is derived synchronously from the slugs each render and is a fresh
 // object every time, so depending on it would re-run this effect on every
 // render. Depend on the stable slug strings instead.
 // eslint-disable-next-line react-hooks/exhaustive-deps
 }, [componentSlug, storySlug]);

 if (!found) {
 return <div className='text-muted-foreground p-8 text-sm'>Story not found.</div>;
Expand Down

9 changes: 8 additions & 1 deletion
packages/swingset/src/lib/registry.ts

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Original file line numberDiff line numberDiff line change
@@ -1,11 +1,18 @@
// Import stories explicitly to control order and avoid type casting through unknown.
import { Disabled, meta as buttonMeta, Primary, Sizes } from '../stories/button.stories';
import { meta as collapsibleMeta } from '../stories/collapsible.stories';
import { toSlug } from './slug';
import type { StoryModule } from './types';

const buttonModule: StoryModule = { meta: buttonMeta, Primary, Sizes, Disabled };

export const registry: StoryModule[] = [buttonModule];
// Headless primitives are documented as overview-only: the registry entry carries
// just `meta` (no story functions), so the sidebar shows a single "Overview" link and
// no interactive knob canvas. The overview's live demos come from `<Story>` embeds in
// the MDX, which import the stories module directly (not through this registry).
const collapsibleModule: StoryModule = { meta: collapsibleMeta };

export const registry: StoryModule[] = [buttonModule, collapsibleModule];

export interface RegistryEntry {
 mod: StoryModule;
Expand Down

2 changes: 1 addition & 1 deletion
packages/swingset/src/stories/button.mdx

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Expand Up@@ -35,7 +35,7 @@ import { Button } from '@clerk/ui/mosaic/components/button';
 size='md'
>
 Click me
</Button>;
</Button>
```

## Props
Expand Down

94 changes: 94 additions & 0 deletions
packages/swingset/src/stories/collapsible.mdx

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@@ -0,0 +1,94 @@
import * as CollapsibleStories from './collapsible.stories';

# Collapsible

A single show/hide panel toggled by a button, from `@clerk/headless`. It is a
**headless** primitive: it supplies behavior, state, ARIA wiring, and the
expand/collapse animation lifecycle, but ships **no styles** — you bring your own
CSS by targeting the `data-cl-*` attributes each part emits.

## Example

The demo below is intentionally unstyled — it renders the raw primitive so you can see
its behavior and ARIA wiring. Click the trigger to expand and collapse.

<Story
 name='Default'
 storyModule={CollapsibleStories}
/>

## Usage

```tsx
import { Collapsible } from '@clerk/headless/collapsible';

<Collapsible.Root>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

### Controlled

```tsx
const [open, setOpen] = useState(false);

<Collapsible.Root
 open={open}
 onOpenChange={setOpen}
>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

## Parts

| Part | Default Element | Description |
| --------------------- | --------------- | ---------------------------------- |
| `Collapsible.Root` | `<div>` | Root wrapper, provides context |
| `Collapsible.Trigger` | `<button>` | Clickable toggle that opens/closes |
| `Collapsible.Panel` | `<div>` | Collapsible content area |

All parts accept a `render` prop for polymorphic rendering and standard HTML
attributes for their default element.

## Props

### `Collapsible.Root`

| Prop | Type | Default | Description |
| ------------------------- | ------------------------------------ | ------------------ | ---------------------------------- |
| <code>open</code> | <code>boolean</code> | — | Controlled open state |
| <code>defaultOpen</code> | <code>boolean</code> | <code>false</code> | Initial open state (uncontrolled) |
| <code>onOpenChange</code> | <code>(open: boolean) => void</code> | — | Called when open state changes |
| <code>disabled</code> | <code>boolean</code> | <code>false</code> | Prevents the trigger from toggling |

`Collapsible.Trigger` and `Collapsible.Panel` take no additional props beyond
standard HTML attributes for their default element.

## Styling

Each part emits `data-cl-*` attributes you can target with any CSS solution:

| Attribute | Applies To | Description |
| ------------------ | -------------------- | -------------------------------- |
| `data-cl-slot` | All parts | Part identifier |
| `data-cl-open` | Root, Trigger, Panel | Present when the panel is open |
| `data-cl-closed` | Root, Trigger, Panel | Present when the panel is closed |
| `data-cl-disabled` | Root, Trigger | Present when disabled |

`Collapsible.Panel` also exposes `--collapsible-panel-height` /
`--collapsible-panel-width` (its measured dimensions) for height/width-based
animations:

```css
[data-cl-slot='collapsible-panel'] {
 overflow: hidden;
 height: var(--collapsible-panel-height);
 transition: height 200ms ease;
}
[data-cl-slot='collapsible-panel'][data-cl-closed] {
 height: 0;
}
```

27 changes: 27 additions & 0 deletions
packages/swingset/src/stories/collapsible.stories.tsx

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@@ -0,0 +1,27 @@
import { Collapsible } from '@clerk/headless/collapsible';

import type { StoryMeta } from '@/lib/types';

// Headless primitives ship no styles. This single demo renders the primitive raw —
// unstyled — so it faithfully reflects what `@clerk/headless` provides: behavior, state,
// and ARIA wiring via the `data-cl-*` attributes each part emits, with zero appearance.
// It is embedded once into the overview via `<Story>` in the MDX (the one thing prose
// can't convey: that it actually expands/collapses). There is no interactive knob canvas
// for headless primitives.

export const meta: StoryMeta = {
 group: 'Primitives',
 title: 'Collapsible',
};

export function Default() {
 return (
 <Collapsible.Root>
 <Collapsible.Trigger>What is a headless component?</Collapsible.Trigger>
 <Collapsible.Panel>
 A headless component provides behavior, state management, and accessibility without imposing any styles — you
 bring your own CSS via the <code>data-cl-slot</code> attributes it emits.
 </Collapsible.Panel>
 </Collapsible.Root>
 );
}

3 changes: 2 additions & 1 deletion
packages/swingset/tsconfig.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -13,7 +13,8 @@
 "paths": {
 "@/*": ["./src/*"],
 "@clerk/ui/mosaic": ["../ui/src/mosaic"],
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"]
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"],
 "@clerk/headless/*": ["../headless/src/primitives/*"]
 },
 "plugins": [
 {
Expand Down

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pnpm-lock.yaml

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Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.


10 changes: 10 additions & 0 deletions
prettier.config.mjs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -9,4 +9,14 @@ export default {
 singleQuote: true,
 tabWidth: 2,
 trailingComma: 'all',
 overrides: [
 {
 // Leave fenced code samples in MDX docs exactly as authored. Without this,
 // `semi: true` reformats the embedded code and re-adds trailing semicolons to
 // JSX usage examples (e.g. `</Collapsible.Root>;`). Markdown prose and tables
 // are still formatted as normal.
 files: '*.mdx',
 options: { embeddedLanguageFormatting: 'off' },
 },
 ],
};
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
docs(swingset): document Collapsible headless primitive by kylemac · Pull Request #8809 · clerk/javascript · GitHub
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Jun 10, 2026
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docs(swingset): document Collapsible headless primitive
#8809
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2 changes: 2 additions & 0 deletions
.changeset/document-headless-collapsible.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,2 @@
---
---

2 changes: 2 additions & 0 deletions
packages/swingset/next.config.mjs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -29,6 +29,8 @@ const nextConfig = {
 },
 webpack(config) {
 config.resolve.alias['@clerk/ui/mosaic'] = resolve(__dirname, '../ui/src/mosaic');
 // Consume @clerk/headless primitives from source (no dist build needed), mirroring Mosaic.
 config.resolve.alias['@clerk/headless'] = resolve(__dirname, '../headless/src/primitives');
 return config;
 },
};
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/package.json

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@
 },
 "dependencies": {
 "@base-ui/react": "^1.5.0",
 "@clerk/headless": "workspace:*",
 "@clerk/ui": "workspace:*",
 "@emotion/react": "^11.11.1",
 "@tailwindcss/typography": "^0.5.19",
Expand Down

16 changes: 9 additions & 7 deletions
packages/swingset/src/app/layout.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,13 +22,15 @@ export default function RootLayout({ children }: { children: React.ReactNode })
 suppressHydrationWarning
 className={cn('font-sans', geist.variable)}
 >
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 <head>
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 </head>
 <body className='antialiased'>
 <ThemeProvider>
 <ClientRoot>{children}</ClientRoot>
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/src/components/DocsViewer.tsx

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4,6 +4,7 @@ import dynamic from 'next/dynamic';

const docModules: Record<string, React.ComponentType> = {
 button: dynamic(() => import('../stories/button.mdx')),
 collapsible: dynamic(() => import('../stories/collapsible.mdx')),
};

interface DocsViewerProps {
Expand Down

6 changes: 5 additions & 1 deletion
packages/swingset/src/components/StoryCanvas.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -32,7 +32,11 @@ export function StoryCanvas({ componentSlug, storySlug }: StoryCanvasProps) {
 const nextKnobs = generateKnobs(found.mod.meta);
 setKnobs(nextKnobs);
 setKnobValues(initKnobValues(nextKnobs));
 }, [found, componentSlug, storySlug]);
 // `found` is derived synchronously from the slugs each render and is a fresh
 // object every time, so depending on it would re-run this effect on every
 // render. Depend on the stable slug strings instead.
 // eslint-disable-next-line react-hooks/exhaustive-deps
 }, [componentSlug, storySlug]);

 if (!found) {
 return <div className='text-muted-foreground p-8 text-sm'>Story not found.</div>;
Expand Down

9 changes: 8 additions & 1 deletion
packages/swingset/src/lib/registry.ts

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Original file line numberDiff line numberDiff line change
@@ -1,11 +1,18 @@
// Import stories explicitly to control order and avoid type casting through unknown.
import { Disabled, meta as buttonMeta, Primary, Sizes } from '../stories/button.stories';
import { meta as collapsibleMeta } from '../stories/collapsible.stories';
import { toSlug } from './slug';
import type { StoryModule } from './types';

const buttonModule: StoryModule = { meta: buttonMeta, Primary, Sizes, Disabled };

export const registry: StoryModule[] = [buttonModule];
// Headless primitives are documented as overview-only: the registry entry carries
// just `meta` (no story functions), so the sidebar shows a single "Overview" link and
// no interactive knob canvas. The overview's live demos come from `<Story>` embeds in
// the MDX, which import the stories module directly (not through this registry).
const collapsibleModule: StoryModule = { meta: collapsibleMeta };

export const registry: StoryModule[] = [buttonModule, collapsibleModule];

export interface RegistryEntry {
 mod: StoryModule;
Expand Down

2 changes: 1 addition & 1 deletion
packages/swingset/src/stories/button.mdx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -35,7 +35,7 @@ import { Button } from '@clerk/ui/mosaic/components/button';
 size='md'
>
 Click me
</Button>;
</Button>
```

## Props
Expand Down

94 changes: 94 additions & 0 deletions
packages/swingset/src/stories/collapsible.mdx

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,94 @@
import * as CollapsibleStories from './collapsible.stories';

# Collapsible

A single show/hide panel toggled by a button, from `@clerk/headless`. It is a
**headless** primitive: it supplies behavior, state, ARIA wiring, and the
expand/collapse animation lifecycle, but ships **no styles** — you bring your own
CSS by targeting the `data-cl-*` attributes each part emits.

## Example

The demo below is intentionally unstyled — it renders the raw primitive so you can see
its behavior and ARIA wiring. Click the trigger to expand and collapse.

<Story
 name='Default'
 storyModule={CollapsibleStories}
/>

## Usage

```tsx
import { Collapsible } from '@clerk/headless/collapsible';

<Collapsible.Root>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

### Controlled

```tsx
const [open, setOpen] = useState(false);

<Collapsible.Root
 open={open}
 onOpenChange={setOpen}
>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

## Parts

| Part | Default Element | Description |
| --------------------- | --------------- | ---------------------------------- |
| `Collapsible.Root` | `<div>` | Root wrapper, provides context |
| `Collapsible.Trigger` | `<button>` | Clickable toggle that opens/closes |
| `Collapsible.Panel` | `<div>` | Collapsible content area |

All parts accept a `render` prop for polymorphic rendering and standard HTML
attributes for their default element.

## Props

### `Collapsible.Root`

| Prop | Type | Default | Description |
| ------------------------- | ------------------------------------ | ------------------ | ---------------------------------- |
| <code>open</code> | <code>boolean</code> | — | Controlled open state |
| <code>defaultOpen</code> | <code>boolean</code> | <code>false</code> | Initial open state (uncontrolled) |
| <code>onOpenChange</code> | <code>(open: boolean) => void</code> | — | Called when open state changes |
| <code>disabled</code> | <code>boolean</code> | <code>false</code> | Prevents the trigger from toggling |

`Collapsible.Trigger` and `Collapsible.Panel` take no additional props beyond
standard HTML attributes for their default element.

## Styling

Each part emits `data-cl-*` attributes you can target with any CSS solution:

| Attribute | Applies To | Description |
| ------------------ | -------------------- | -------------------------------- |
| `data-cl-slot` | All parts | Part identifier |
| `data-cl-open` | Root, Trigger, Panel | Present when the panel is open |
| `data-cl-closed` | Root, Trigger, Panel | Present when the panel is closed |
| `data-cl-disabled` | Root, Trigger | Present when disabled |

`Collapsible.Panel` also exposes `--collapsible-panel-height` /
`--collapsible-panel-width` (its measured dimensions) for height/width-based
animations:

```css
[data-cl-slot='collapsible-panel'] {
 overflow: hidden;
 height: var(--collapsible-panel-height);
 transition: height 200ms ease;
}
[data-cl-slot='collapsible-panel'][data-cl-closed] {
 height: 0;
}
```

27 changes: 27 additions & 0 deletions
packages/swingset/src/stories/collapsible.stories.tsx

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,27 @@
import { Collapsible } from '@clerk/headless/collapsible';

import type { StoryMeta } from '@/lib/types';

// Headless primitives ship no styles. This single demo renders the primitive raw —
// unstyled — so it faithfully reflects what `@clerk/headless` provides: behavior, state,
// and ARIA wiring via the `data-cl-*` attributes each part emits, with zero appearance.
// It is embedded once into the overview via `<Story>` in the MDX (the one thing prose
// can't convey: that it actually expands/collapses). There is no interactive knob canvas
// for headless primitives.

export const meta: StoryMeta = {
 group: 'Primitives',
 title: 'Collapsible',
};

export function Default() {
 return (
 <Collapsible.Root>
 <Collapsible.Trigger>What is a headless component?</Collapsible.Trigger>
 <Collapsible.Panel>
 A headless component provides behavior, state management, and accessibility without imposing any styles — you
 bring your own CSS via the <code>data-cl-slot</code> attributes it emits.
 </Collapsible.Panel>
 </Collapsible.Root>
 );
}

3 changes: 2 additions & 1 deletion
packages/swingset/tsconfig.json

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -13,7 +13,8 @@
 "paths": {
 "@/*": ["./src/*"],
 "@clerk/ui/mosaic": ["../ui/src/mosaic"],
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"]
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"],
 "@clerk/headless/*": ["../headless/src/primitives/*"]
 },
 "plugins": [
 {
Expand Down

3 changes: 3 additions & 0 deletions
pnpm-lock.yaml

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Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.


10 changes: 10 additions & 0 deletions
prettier.config.mjs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -9,4 +9,14 @@ export default {
 singleQuote: true,
 tabWidth: 2,
 trailingComma: 'all',
 overrides: [
 {
 // Leave fenced code samples in MDX docs exactly as authored. Without this,
 // `semi: true` reformats the embedded code and re-adds trailing semicolons to
 // JSX usage examples (e.g. `</Collapsible.Root>;`). Markdown prose and tables
 // are still formatted as normal.
 files: '*.mdx',
 options: { embeddedLanguageFormatting: 'off' },
 },
 ],
};
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
docs(swingset): document Collapsible headless primitive by kylemac · Pull Request #8809 · clerk/javascript · GitHub
Skip to content
docs(swingset): document Collapsible headless primitive#8809

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merged 1 commit into

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Jun 10, 2026
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docs(swingset): document Collapsible headless primitive
#8809
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2 changes: 2 additions & 0 deletions
.changeset/document-headless-collapsible.md

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,2 @@
---
---

2 changes: 2 additions & 0 deletions
packages/swingset/next.config.mjs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -29,6 +29,8 @@ const nextConfig = {
 },
 webpack(config) {
 config.resolve.alias['@clerk/ui/mosaic'] = resolve(__dirname, '../ui/src/mosaic');
 // Consume @clerk/headless primitives from source (no dist build needed), mirroring Mosaic.
 config.resolve.alias['@clerk/headless'] = resolve(__dirname, '../headless/src/primitives');
 return config;
 },
};
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@
 },
 "dependencies": {
 "@base-ui/react": "^1.5.0",
 "@clerk/headless": "workspace:*",
 "@clerk/ui": "workspace:*",
 "@emotion/react": "^11.11.1",
 "@tailwindcss/typography": "^0.5.19",
Expand Down

16 changes: 9 additions & 7 deletions
packages/swingset/src/app/layout.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -22,13 +22,15 @@ export default function RootLayout({ children }: { children: React.ReactNode })
 suppressHydrationWarning
 className={cn('font-sans', geist.variable)}
 >
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 <head>
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 </head>
 <body className='antialiased'>
 <ThemeProvider>
 <ClientRoot>{children}</ClientRoot>
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/src/components/DocsViewer.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -4,6 +4,7 @@ import dynamic from 'next/dynamic';

const docModules: Record<string, React.ComponentType> = {
 button: dynamic(() => import('../stories/button.mdx')),
 collapsible: dynamic(() => import('../stories/collapsible.mdx')),
};

interface DocsViewerProps {
Expand Down

6 changes: 5 additions & 1 deletion
packages/swingset/src/components/StoryCanvas.tsx

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Expand Up@@ -32,7 +32,11 @@ export function StoryCanvas({ componentSlug, storySlug }: StoryCanvasProps) {
 const nextKnobs = generateKnobs(found.mod.meta);
 setKnobs(nextKnobs);
 setKnobValues(initKnobValues(nextKnobs));
 }, [found, componentSlug, storySlug]);
 // `found` is derived synchronously from the slugs each render and is a fresh
 // object every time, so depending on it would re-run this effect on every
 // render. Depend on the stable slug strings instead.
 // eslint-disable-next-line react-hooks/exhaustive-deps
 }, [componentSlug, storySlug]);

 if (!found) {
 return <div className='text-muted-foreground p-8 text-sm'>Story not found.</div>;
Expand Down

9 changes: 8 additions & 1 deletion
packages/swingset/src/lib/registry.ts

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@@ -1,11 +1,18 @@
// Import stories explicitly to control order and avoid type casting through unknown.
import { Disabled, meta as buttonMeta, Primary, Sizes } from '../stories/button.stories';
import { meta as collapsibleMeta } from '../stories/collapsible.stories';
import { toSlug } from './slug';
import type { StoryModule } from './types';

const buttonModule: StoryModule = { meta: buttonMeta, Primary, Sizes, Disabled };

export const registry: StoryModule[] = [buttonModule];
// Headless primitives are documented as overview-only: the registry entry carries
// just `meta` (no story functions), so the sidebar shows a single "Overview" link and
// no interactive knob canvas. The overview's live demos come from `<Story>` embeds in
// the MDX, which import the stories module directly (not through this registry).
const collapsibleModule: StoryModule = { meta: collapsibleMeta };

export const registry: StoryModule[] = [buttonModule, collapsibleModule];

export interface RegistryEntry {
 mod: StoryModule;
Expand Down

2 changes: 1 addition & 1 deletion
packages/swingset/src/stories/button.mdx

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Expand Up@@ -35,7 +35,7 @@ import { Button } from '@clerk/ui/mosaic/components/button';
 size='md'
>
 Click me
</Button>;
</Button>
```

## Props
Expand Down

94 changes: 94 additions & 0 deletions
packages/swingset/src/stories/collapsible.mdx

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@@ -0,0 +1,94 @@
import * as CollapsibleStories from './collapsible.stories';

# Collapsible

A single show/hide panel toggled by a button, from `@clerk/headless`. It is a
**headless** primitive: it supplies behavior, state, ARIA wiring, and the
expand/collapse animation lifecycle, but ships **no styles** — you bring your own
CSS by targeting the `data-cl-*` attributes each part emits.

## Example

The demo below is intentionally unstyled — it renders the raw primitive so you can see
its behavior and ARIA wiring. Click the trigger to expand and collapse.

<Story
 name='Default'
 storyModule={CollapsibleStories}
/>

## Usage

```tsx
import { Collapsible } from '@clerk/headless/collapsible';

<Collapsible.Root>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

### Controlled

```tsx
const [open, setOpen] = useState(false);

<Collapsible.Root
 open={open}
 onOpenChange={setOpen}
>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

## Parts

| Part | Default Element | Description |
| --------------------- | --------------- | ---------------------------------- |
| `Collapsible.Root` | `<div>` | Root wrapper, provides context |
| `Collapsible.Trigger` | `<button>` | Clickable toggle that opens/closes |
| `Collapsible.Panel` | `<div>` | Collapsible content area |

All parts accept a `render` prop for polymorphic rendering and standard HTML
attributes for their default element.

## Props

### `Collapsible.Root`

| Prop | Type | Default | Description |
| ------------------------- | ------------------------------------ | ------------------ | ---------------------------------- |
| <code>open</code> | <code>boolean</code> | — | Controlled open state |
| <code>defaultOpen</code> | <code>boolean</code> | <code>false</code> | Initial open state (uncontrolled) |
| <code>onOpenChange</code> | <code>(open: boolean) => void</code> | — | Called when open state changes |
| <code>disabled</code> | <code>boolean</code> | <code>false</code> | Prevents the trigger from toggling |

`Collapsible.Trigger` and `Collapsible.Panel` take no additional props beyond
standard HTML attributes for their default element.

## Styling

Each part emits `data-cl-*` attributes you can target with any CSS solution:

| Attribute | Applies To | Description |
| ------------------ | -------------------- | -------------------------------- |
| `data-cl-slot` | All parts | Part identifier |
| `data-cl-open` | Root, Trigger, Panel | Present when the panel is open |
| `data-cl-closed` | Root, Trigger, Panel | Present when the panel is closed |
| `data-cl-disabled` | Root, Trigger | Present when disabled |

`Collapsible.Panel` also exposes `--collapsible-panel-height` /
`--collapsible-panel-width` (its measured dimensions) for height/width-based
animations:

```css
[data-cl-slot='collapsible-panel'] {
 overflow: hidden;
 height: var(--collapsible-panel-height);
 transition: height 200ms ease;
}
[data-cl-slot='collapsible-panel'][data-cl-closed] {
 height: 0;
}
```

27 changes: 27 additions & 0 deletions
packages/swingset/src/stories/collapsible.stories.tsx

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@@ -0,0 +1,27 @@
import { Collapsible } from '@clerk/headless/collapsible';

import type { StoryMeta } from '@/lib/types';

// Headless primitives ship no styles. This single demo renders the primitive raw —
// unstyled — so it faithfully reflects what `@clerk/headless` provides: behavior, state,
// and ARIA wiring via the `data-cl-*` attributes each part emits, with zero appearance.
// It is embedded once into the overview via `<Story>` in the MDX (the one thing prose
// can't convey: that it actually expands/collapses). There is no interactive knob canvas
// for headless primitives.

export const meta: StoryMeta = {
 group: 'Primitives',
 title: 'Collapsible',
};

export function Default() {
 return (
 <Collapsible.Root>
 <Collapsible.Trigger>What is a headless component?</Collapsible.Trigger>
 <Collapsible.Panel>
 A headless component provides behavior, state management, and accessibility without imposing any styles — you
 bring your own CSS via the <code>data-cl-slot</code> attributes it emits.
 </Collapsible.Panel>
 </Collapsible.Root>
 );
}

3 changes: 2 additions & 1 deletion
packages/swingset/tsconfig.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -13,7 +13,8 @@
 "paths": {
 "@/*": ["./src/*"],
 "@clerk/ui/mosaic": ["../ui/src/mosaic"],
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"]
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"],
 "@clerk/headless/*": ["../headless/src/primitives/*"]
 },
 "plugins": [
 {
Expand Down

3 changes: 3 additions & 0 deletions
pnpm-lock.yaml

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Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.


10 changes: 10 additions & 0 deletions
prettier.config.mjs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -9,4 +9,14 @@ export default {
 singleQuote: true,
 tabWidth: 2,
 trailingComma: 'all',
 overrides: [
 {
 // Leave fenced code samples in MDX docs exactly as authored. Without this,
 // `semi: true` reformats the embedded code and re-adds trailing semicolons to
 // JSX usage examples (e.g. `</Collapsible.Root>;`). Markdown prose and tables
 // are still formatted as normal.
 files: '*.mdx',
 options: { embeddedLanguageFormatting: 'off' },
 },
 ],
};
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
docs(swingset): document Collapsible headless primitive by kylemac · Pull Request #8809 · clerk/javascript · GitHub
Skip to content
docs(swingset): document Collapsible headless primitive#8809

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 Merged

kylemac
merged 1 commit into

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Jun 10, 2026
 Merged


docs(swingset): document Collapsible headless primitive
#8809
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2 changes: 2 additions & 0 deletions
.changeset/document-headless-collapsible.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,2 @@
---
---

2 changes: 2 additions & 0 deletions
packages/swingset/next.config.mjs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -29,6 +29,8 @@ const nextConfig = {
 },
 webpack(config) {
 config.resolve.alias['@clerk/ui/mosaic'] = resolve(__dirname, '../ui/src/mosaic');
 // Consume @clerk/headless primitives from source (no dist build needed), mirroring Mosaic.
 config.resolve.alias['@clerk/headless'] = resolve(__dirname, '../headless/src/primitives');
 return config;
 },
};
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/package.json

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@
 },
 "dependencies": {
 "@base-ui/react": "^1.5.0",
 "@clerk/headless": "workspace:*",
 "@clerk/ui": "workspace:*",
 "@emotion/react": "^11.11.1",
 "@tailwindcss/typography": "^0.5.19",
Expand Down

16 changes: 9 additions & 7 deletions
packages/swingset/src/app/layout.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,13 +22,15 @@ export default function RootLayout({ children }: { children: React.ReactNode })
 suppressHydrationWarning
 className={cn('font-sans', geist.variable)}
 >
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 <head>
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 </head>
 <body className='antialiased'>
 <ThemeProvider>
 <ClientRoot>{children}</ClientRoot>
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/src/components/DocsViewer.tsx

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4,6 +4,7 @@ import dynamic from 'next/dynamic';

const docModules: Record<string, React.ComponentType> = {
 button: dynamic(() => import('../stories/button.mdx')),
 collapsible: dynamic(() => import('../stories/collapsible.mdx')),
};

interface DocsViewerProps {
Expand Down

6 changes: 5 additions & 1 deletion
packages/swingset/src/components/StoryCanvas.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -32,7 +32,11 @@ export function StoryCanvas({ componentSlug, storySlug }: StoryCanvasProps) {
 const nextKnobs = generateKnobs(found.mod.meta);
 setKnobs(nextKnobs);
 setKnobValues(initKnobValues(nextKnobs));
 }, [found, componentSlug, storySlug]);
 // `found` is derived synchronously from the slugs each render and is a fresh
 // object every time, so depending on it would re-run this effect on every
 // render. Depend on the stable slug strings instead.
 // eslint-disable-next-line react-hooks/exhaustive-deps
 }, [componentSlug, storySlug]);

 if (!found) {
 return <div className='text-muted-foreground p-8 text-sm'>Story not found.</div>;
Expand Down

9 changes: 8 additions & 1 deletion
packages/swingset/src/lib/registry.ts

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Original file line numberDiff line numberDiff line change
@@ -1,11 +1,18 @@
// Import stories explicitly to control order and avoid type casting through unknown.
import { Disabled, meta as buttonMeta, Primary, Sizes } from '../stories/button.stories';
import { meta as collapsibleMeta } from '../stories/collapsible.stories';
import { toSlug } from './slug';
import type { StoryModule } from './types';

const buttonModule: StoryModule = { meta: buttonMeta, Primary, Sizes, Disabled };

export const registry: StoryModule[] = [buttonModule];
// Headless primitives are documented as overview-only: the registry entry carries
// just `meta` (no story functions), so the sidebar shows a single "Overview" link and
// no interactive knob canvas. The overview's live demos come from `<Story>` embeds in
// the MDX, which import the stories module directly (not through this registry).
const collapsibleModule: StoryModule = { meta: collapsibleMeta };

export const registry: StoryModule[] = [buttonModule, collapsibleModule];

export interface RegistryEntry {
 mod: StoryModule;
Expand Down

2 changes: 1 addition & 1 deletion
packages/swingset/src/stories/button.mdx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -35,7 +35,7 @@ import { Button } from '@clerk/ui/mosaic/components/button';
 size='md'
>
 Click me
</Button>;
</Button>
```

## Props
Expand Down

94 changes: 94 additions & 0 deletions
packages/swingset/src/stories/collapsible.mdx

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,94 @@
import * as CollapsibleStories from './collapsible.stories';

# Collapsible

A single show/hide panel toggled by a button, from `@clerk/headless`. It is a
**headless** primitive: it supplies behavior, state, ARIA wiring, and the
expand/collapse animation lifecycle, but ships **no styles** — you bring your own
CSS by targeting the `data-cl-*` attributes each part emits.

## Example

The demo below is intentionally unstyled — it renders the raw primitive so you can see
its behavior and ARIA wiring. Click the trigger to expand and collapse.

<Story
 name='Default'
 storyModule={CollapsibleStories}
/>

## Usage

```tsx
import { Collapsible } from '@clerk/headless/collapsible';

<Collapsible.Root>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

### Controlled

```tsx
const [open, setOpen] = useState(false);

<Collapsible.Root
 open={open}
 onOpenChange={setOpen}
>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

## Parts

| Part | Default Element | Description |
| --------------------- | --------------- | ---------------------------------- |
| `Collapsible.Root` | `<div>` | Root wrapper, provides context |
| `Collapsible.Trigger` | `<button>` | Clickable toggle that opens/closes |
| `Collapsible.Panel` | `<div>` | Collapsible content area |

All parts accept a `render` prop for polymorphic rendering and standard HTML
attributes for their default element.

## Props

### `Collapsible.Root`

| Prop | Type | Default | Description |
| ------------------------- | ------------------------------------ | ------------------ | ---------------------------------- |
| <code>open</code> | <code>boolean</code> | — | Controlled open state |
| <code>defaultOpen</code> | <code>boolean</code> | <code>false</code> | Initial open state (uncontrolled) |
| <code>onOpenChange</code> | <code>(open: boolean) => void</code> | — | Called when open state changes |
| <code>disabled</code> | <code>boolean</code> | <code>false</code> | Prevents the trigger from toggling |

`Collapsible.Trigger` and `Collapsible.Panel` take no additional props beyond
standard HTML attributes for their default element.

## Styling

Each part emits `data-cl-*` attributes you can target with any CSS solution:

| Attribute | Applies To | Description |
| ------------------ | -------------------- | -------------------------------- |
| `data-cl-slot` | All parts | Part identifier |
| `data-cl-open` | Root, Trigger, Panel | Present when the panel is open |
| `data-cl-closed` | Root, Trigger, Panel | Present when the panel is closed |
| `data-cl-disabled` | Root, Trigger | Present when disabled |

`Collapsible.Panel` also exposes `--collapsible-panel-height` /
`--collapsible-panel-width` (its measured dimensions) for height/width-based
animations:

```css
[data-cl-slot='collapsible-panel'] {
 overflow: hidden;
 height: var(--collapsible-panel-height);
 transition: height 200ms ease;
}
[data-cl-slot='collapsible-panel'][data-cl-closed] {
 height: 0;
}
```

27 changes: 27 additions & 0 deletions
packages/swingset/src/stories/collapsible.stories.tsx

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,27 @@
import { Collapsible } from '@clerk/headless/collapsible';

import type { StoryMeta } from '@/lib/types';

// Headless primitives ship no styles. This single demo renders the primitive raw —
// unstyled — so it faithfully reflects what `@clerk/headless` provides: behavior, state,
// and ARIA wiring via the `data-cl-*` attributes each part emits, with zero appearance.
// It is embedded once into the overview via `<Story>` in the MDX (the one thing prose
// can't convey: that it actually expands/collapses). There is no interactive knob canvas
// for headless primitives.

export const meta: StoryMeta = {
 group: 'Primitives',
 title: 'Collapsible',
};

export function Default() {
 return (
 <Collapsible.Root>
 <Collapsible.Trigger>What is a headless component?</Collapsible.Trigger>
 <Collapsible.Panel>
 A headless component provides behavior, state management, and accessibility without imposing any styles — you
 bring your own CSS via the <code>data-cl-slot</code> attributes it emits.
 </Collapsible.Panel>
 </Collapsible.Root>
 );
}

3 changes: 2 additions & 1 deletion
packages/swingset/tsconfig.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -13,7 +13,8 @@
 "paths": {
 "@/*": ["./src/*"],
 "@clerk/ui/mosaic": ["../ui/src/mosaic"],
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"]
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"],
 "@clerk/headless/*": ["../headless/src/primitives/*"]
 },
 "plugins": [
 {
Expand Down

3 changes: 3 additions & 0 deletions
pnpm-lock.yaml

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Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.


10 changes: 10 additions & 0 deletions
prettier.config.mjs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -9,4 +9,14 @@ export default {
 singleQuote: true,
 tabWidth: 2,
 trailingComma: 'all',
 overrides: [
 {
 // Leave fenced code samples in MDX docs exactly as authored. Without this,
 // `semi: true` reformats the embedded code and re-adds trailing semicolons to
 // JSX usage examples (e.g. `</Collapsible.Root>;`). Markdown prose and tables
 // are still formatted as normal.
 files: '*.mdx',
 options: { embeddedLanguageFormatting: 'off' },
 },
 ],
};
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
docs(swingset): document Collapsible headless primitive by kylemac · Pull Request #8809 · clerk/javascript · GitHub
Skip to content
docs(swingset): document Collapsible headless primitive#8809

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privacy statement. We’ll occasionally send you account related emails.

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 Merged

kylemac
merged 1 commit into

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Jun 10, 2026
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docs(swingset): document Collapsible headless primitive
#8809
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2 changes: 2 additions & 0 deletions
.changeset/document-headless-collapsible.md

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@@ -0,0 +1,2 @@
---
---

2 changes: 2 additions & 0 deletions
packages/swingset/next.config.mjs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -29,6 +29,8 @@ const nextConfig = {
 },
 webpack(config) {
 config.resolve.alias['@clerk/ui/mosaic'] = resolve(__dirname, '../ui/src/mosaic');
 // Consume @clerk/headless primitives from source (no dist build needed), mirroring Mosaic.
 config.resolve.alias['@clerk/headless'] = resolve(__dirname, '../headless/src/primitives');
 return config;
 },
};
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1 change: 1 addition & 0 deletions
packages/swingset/package.json

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Expand Up@@ -11,6 +11,7 @@
 },
 "dependencies": {
 "@base-ui/react": "^1.5.0",
 "@clerk/headless": "workspace:*",
 "@clerk/ui": "workspace:*",
 "@emotion/react": "^11.11.1",
 "@tailwindcss/typography": "^0.5.19",
Expand Down

16 changes: 9 additions & 7 deletions
packages/swingset/src/app/layout.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -22,13 +22,15 @@ export default function RootLayout({ children }: { children: React.ReactNode })
 suppressHydrationWarning
 className={cn('font-sans', geist.variable)}
 >
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 <head>
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 </head>
 <body className='antialiased'>
 <ThemeProvider>
 <ClientRoot>{children}</ClientRoot>
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1 change: 1 addition & 0 deletions
packages/swingset/src/components/DocsViewer.tsx

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Expand Up@@ -4,6 +4,7 @@ import dynamic from 'next/dynamic';

const docModules: Record<string, React.ComponentType> = {
 button: dynamic(() => import('../stories/button.mdx')),
 collapsible: dynamic(() => import('../stories/collapsible.mdx')),
};

interface DocsViewerProps {
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6 changes: 5 additions & 1 deletion
packages/swingset/src/components/StoryCanvas.tsx

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Expand Up@@ -32,7 +32,11 @@ export function StoryCanvas({ componentSlug, storySlug }: StoryCanvasProps) {
 const nextKnobs = generateKnobs(found.mod.meta);
 setKnobs(nextKnobs);
 setKnobValues(initKnobValues(nextKnobs));
 }, [found, componentSlug, storySlug]);
 // `found` is derived synchronously from the slugs each render and is a fresh
 // object every time, so depending on it would re-run this effect on every
 // render. Depend on the stable slug strings instead.
 // eslint-disable-next-line react-hooks/exhaustive-deps
 }, [componentSlug, storySlug]);

 if (!found) {
 return <div className='text-muted-foreground p-8 text-sm'>Story not found.</div>;
Expand Down

9 changes: 8 additions & 1 deletion
packages/swingset/src/lib/registry.ts

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@@ -1,11 +1,18 @@
// Import stories explicitly to control order and avoid type casting through unknown.
import { Disabled, meta as buttonMeta, Primary, Sizes } from '../stories/button.stories';
import { meta as collapsibleMeta } from '../stories/collapsible.stories';
import { toSlug } from './slug';
import type { StoryModule } from './types';

const buttonModule: StoryModule = { meta: buttonMeta, Primary, Sizes, Disabled };

export const registry: StoryModule[] = [buttonModule];
// Headless primitives are documented as overview-only: the registry entry carries
// just `meta` (no story functions), so the sidebar shows a single "Overview" link and
// no interactive knob canvas. The overview's live demos come from `<Story>` embeds in
// the MDX, which import the stories module directly (not through this registry).
const collapsibleModule: StoryModule = { meta: collapsibleMeta };

export const registry: StoryModule[] = [buttonModule, collapsibleModule];

export interface RegistryEntry {
 mod: StoryModule;
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2 changes: 1 addition & 1 deletion
packages/swingset/src/stories/button.mdx

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Expand Up@@ -35,7 +35,7 @@ import { Button } from '@clerk/ui/mosaic/components/button';
 size='md'
>
 Click me
</Button>;
</Button>
```

## Props
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94 changes: 94 additions & 0 deletions
packages/swingset/src/stories/collapsible.mdx

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@@ -0,0 +1,94 @@
import * as CollapsibleStories from './collapsible.stories';

# Collapsible

A single show/hide panel toggled by a button, from `@clerk/headless`. It is a
**headless** primitive: it supplies behavior, state, ARIA wiring, and the
expand/collapse animation lifecycle, but ships **no styles** — you bring your own
CSS by targeting the `data-cl-*` attributes each part emits.

## Example

The demo below is intentionally unstyled — it renders the raw primitive so you can see
its behavior and ARIA wiring. Click the trigger to expand and collapse.

<Story
 name='Default'
 storyModule={CollapsibleStories}
/>

## Usage

```tsx
import { Collapsible } from '@clerk/headless/collapsible';

<Collapsible.Root>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

### Controlled

```tsx
const [open, setOpen] = useState(false);

<Collapsible.Root
 open={open}
 onOpenChange={setOpen}
>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

## Parts

| Part | Default Element | Description |
| --------------------- | --------------- | ---------------------------------- |
| `Collapsible.Root` | `<div>` | Root wrapper, provides context |
| `Collapsible.Trigger` | `<button>` | Clickable toggle that opens/closes |
| `Collapsible.Panel` | `<div>` | Collapsible content area |

All parts accept a `render` prop for polymorphic rendering and standard HTML
attributes for their default element.

## Props

### `Collapsible.Root`

| Prop | Type | Default | Description |
| ------------------------- | ------------------------------------ | ------------------ | ---------------------------------- |
| <code>open</code> | <code>boolean</code> | — | Controlled open state |
| <code>defaultOpen</code> | <code>boolean</code> | <code>false</code> | Initial open state (uncontrolled) |
| <code>onOpenChange</code> | <code>(open: boolean) => void</code> | — | Called when open state changes |
| <code>disabled</code> | <code>boolean</code> | <code>false</code> | Prevents the trigger from toggling |

`Collapsible.Trigger` and `Collapsible.Panel` take no additional props beyond
standard HTML attributes for their default element.

## Styling

Each part emits `data-cl-*` attributes you can target with any CSS solution:

| Attribute | Applies To | Description |
| ------------------ | -------------------- | -------------------------------- |
| `data-cl-slot` | All parts | Part identifier |
| `data-cl-open` | Root, Trigger, Panel | Present when the panel is open |
| `data-cl-closed` | Root, Trigger, Panel | Present when the panel is closed |
| `data-cl-disabled` | Root, Trigger | Present when disabled |

`Collapsible.Panel` also exposes `--collapsible-panel-height` /
`--collapsible-panel-width` (its measured dimensions) for height/width-based
animations:

```css
[data-cl-slot='collapsible-panel'] {
 overflow: hidden;
 height: var(--collapsible-panel-height);
 transition: height 200ms ease;
}
[data-cl-slot='collapsible-panel'][data-cl-closed] {
 height: 0;
}
```

27 changes: 27 additions & 0 deletions
packages/swingset/src/stories/collapsible.stories.tsx

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import { Collapsible } from '@clerk/headless/collapsible';

import type { StoryMeta } from '@/lib/types';

// Headless primitives ship no styles. This single demo renders the primitive raw —
// unstyled — so it faithfully reflects what `@clerk/headless` provides: behavior, state,
// and ARIA wiring via the `data-cl-*` attributes each part emits, with zero appearance.
// It is embedded once into the overview via `<Story>` in the MDX (the one thing prose
// can't convey: that it actually expands/collapses). There is no interactive knob canvas
// for headless primitives.

export const meta: StoryMeta = {
 group: 'Primitives',
 title: 'Collapsible',
};

export function Default() {
 return (
 <Collapsible.Root>
 <Collapsible.Trigger>What is a headless component?</Collapsible.Trigger>
 <Collapsible.Panel>
 A headless component provides behavior, state management, and accessibility without imposing any styles — you
 bring your own CSS via the <code>data-cl-slot</code> attributes it emits.
 </Collapsible.Panel>
 </Collapsible.Root>
 );
}

3 changes: 2 additions & 1 deletion
packages/swingset/tsconfig.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -13,7 +13,8 @@
 "paths": {
 "@/*": ["./src/*"],
 "@clerk/ui/mosaic": ["../ui/src/mosaic"],
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"]
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"],
 "@clerk/headless/*": ["../headless/src/primitives/*"]
 },
 "plugins": [
 {
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3 changes: 3 additions & 0 deletions
pnpm-lock.yaml

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Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.


10 changes: 10 additions & 0 deletions
prettier.config.mjs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -9,4 +9,14 @@ export default {
 singleQuote: true,
 tabWidth: 2,
 trailingComma: 'all',
 overrides: [
 {
 // Leave fenced code samples in MDX docs exactly as authored. Without this,
 // `semi: true` reformats the embedded code and re-adds trailing semicolons to
 // JSX usage examples (e.g. `</Collapsible.Root>;`). Markdown prose and tables
 // are still formatted as normal.
 files: '*.mdx',
 options: { embeddedLanguageFormatting: 'off' },
 },
 ],
};
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
docs(swingset): document Collapsible headless primitive by kylemac · Pull Request #8809 · clerk/javascript · GitHub
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 Merged

kylemac
merged 1 commit into

from

Jun 10, 2026
 Merged


docs(swingset): document Collapsible headless primitive
#8809
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2 changes: 2 additions & 0 deletions
.changeset/document-headless-collapsible.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,2 @@
---
---

2 changes: 2 additions & 0 deletions
packages/swingset/next.config.mjs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -29,6 +29,8 @@ const nextConfig = {
 },
 webpack(config) {
 config.resolve.alias['@clerk/ui/mosaic'] = resolve(__dirname, '../ui/src/mosaic');
 // Consume @clerk/headless primitives from source (no dist build needed), mirroring Mosaic.
 config.resolve.alias['@clerk/headless'] = resolve(__dirname, '../headless/src/primitives');
 return config;
 },
};
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@
 },
 "dependencies": {
 "@base-ui/react": "^1.5.0",
 "@clerk/headless": "workspace:*",
 "@clerk/ui": "workspace:*",
 "@emotion/react": "^11.11.1",
 "@tailwindcss/typography": "^0.5.19",
Expand Down

16 changes: 9 additions & 7 deletions
packages/swingset/src/app/layout.tsx

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,13 +22,15 @@ export default function RootLayout({ children }: { children: React.ReactNode })
 suppressHydrationWarning
 className={cn('font-sans', geist.variable)}
 >
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 <head>
 {process.env.NODE_ENV === 'development' && (
 <Script
 src='//unpkg.com/react-grab/dist/index.global.js'
 crossOrigin='anonymous'
 strategy='beforeInteractive'
 />
 )}
 </head>
 <body className='antialiased'>
 <ThemeProvider>
 <ClientRoot>{children}</ClientRoot>
Expand Down

1 change: 1 addition & 0 deletions
packages/swingset/src/components/DocsViewer.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -4,6 +4,7 @@ import dynamic from 'next/dynamic';

const docModules: Record<string, React.ComponentType> = {
 button: dynamic(() => import('../stories/button.mdx')),
 collapsible: dynamic(() => import('../stories/collapsible.mdx')),
};

interface DocsViewerProps {
Expand Down

6 changes: 5 additions & 1 deletion
packages/swingset/src/components/StoryCanvas.tsx

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Expand Up@@ -32,7 +32,11 @@ export function StoryCanvas({ componentSlug, storySlug }: StoryCanvasProps) {
 const nextKnobs = generateKnobs(found.mod.meta);
 setKnobs(nextKnobs);
 setKnobValues(initKnobValues(nextKnobs));
 }, [found, componentSlug, storySlug]);
 // `found` is derived synchronously from the slugs each render and is a fresh
 // object every time, so depending on it would re-run this effect on every
 // render. Depend on the stable slug strings instead.
 // eslint-disable-next-line react-hooks/exhaustive-deps
 }, [componentSlug, storySlug]);

 if (!found) {
 return <div className='text-muted-foreground p-8 text-sm'>Story not found.</div>;
Expand Down

9 changes: 8 additions & 1 deletion
packages/swingset/src/lib/registry.ts

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@@ -1,11 +1,18 @@
// Import stories explicitly to control order and avoid type casting through unknown.
import { Disabled, meta as buttonMeta, Primary, Sizes } from '../stories/button.stories';
import { meta as collapsibleMeta } from '../stories/collapsible.stories';
import { toSlug } from './slug';
import type { StoryModule } from './types';

const buttonModule: StoryModule = { meta: buttonMeta, Primary, Sizes, Disabled };

export const registry: StoryModule[] = [buttonModule];
// Headless primitives are documented as overview-only: the registry entry carries
// just `meta` (no story functions), so the sidebar shows a single "Overview" link and
// no interactive knob canvas. The overview's live demos come from `<Story>` embeds in
// the MDX, which import the stories module directly (not through this registry).
const collapsibleModule: StoryModule = { meta: collapsibleMeta };

export const registry: StoryModule[] = [buttonModule, collapsibleModule];

export interface RegistryEntry {
 mod: StoryModule;
Expand Down

2 changes: 1 addition & 1 deletion
packages/swingset/src/stories/button.mdx

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Expand Up@@ -35,7 +35,7 @@ import { Button } from '@clerk/ui/mosaic/components/button';
 size='md'
>
 Click me
</Button>;
</Button>
```

## Props
Expand Down

94 changes: 94 additions & 0 deletions
packages/swingset/src/stories/collapsible.mdx

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@@ -0,0 +1,94 @@
import * as CollapsibleStories from './collapsible.stories';

# Collapsible

A single show/hide panel toggled by a button, from `@clerk/headless`. It is a
**headless** primitive: it supplies behavior, state, ARIA wiring, and the
expand/collapse animation lifecycle, but ships **no styles** — you bring your own
CSS by targeting the `data-cl-*` attributes each part emits.

## Example

The demo below is intentionally unstyled — it renders the raw primitive so you can see
its behavior and ARIA wiring. Click the trigger to expand and collapse.

<Story
 name='Default'
 storyModule={CollapsibleStories}
/>

## Usage

```tsx
import { Collapsible } from '@clerk/headless/collapsible';

<Collapsible.Root>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

### Controlled

```tsx
const [open, setOpen] = useState(false);

<Collapsible.Root
 open={open}
 onOpenChange={setOpen}
>
 <Collapsible.Trigger>Toggle</Collapsible.Trigger>
 <Collapsible.Panel>Hidden content</Collapsible.Panel>
</Collapsible.Root>
```

## Parts

| Part | Default Element | Description |
| --------------------- | --------------- | ---------------------------------- |
| `Collapsible.Root` | `<div>` | Root wrapper, provides context |
| `Collapsible.Trigger` | `<button>` | Clickable toggle that opens/closes |
| `Collapsible.Panel` | `<div>` | Collapsible content area |

All parts accept a `render` prop for polymorphic rendering and standard HTML
attributes for their default element.

## Props

### `Collapsible.Root`

| Prop | Type | Default | Description |
| ------------------------- | ------------------------------------ | ------------------ | ---------------------------------- |
| <code>open</code> | <code>boolean</code> | — | Controlled open state |
| <code>defaultOpen</code> | <code>boolean</code> | <code>false</code> | Initial open state (uncontrolled) |
| <code>onOpenChange</code> | <code>(open: boolean) => void</code> | — | Called when open state changes |
| <code>disabled</code> | <code>boolean</code> | <code>false</code> | Prevents the trigger from toggling |

`Collapsible.Trigger` and `Collapsible.Panel` take no additional props beyond
standard HTML attributes for their default element.

## Styling

Each part emits `data-cl-*` attributes you can target with any CSS solution:

| Attribute | Applies To | Description |
| ------------------ | -------------------- | -------------------------------- |
| `data-cl-slot` | All parts | Part identifier |
| `data-cl-open` | Root, Trigger, Panel | Present when the panel is open |
| `data-cl-closed` | Root, Trigger, Panel | Present when the panel is closed |
| `data-cl-disabled` | Root, Trigger | Present when disabled |

`Collapsible.Panel` also exposes `--collapsible-panel-height` /
`--collapsible-panel-width` (its measured dimensions) for height/width-based
animations:

```css
[data-cl-slot='collapsible-panel'] {
 overflow: hidden;
 height: var(--collapsible-panel-height);
 transition: height 200ms ease;
}
[data-cl-slot='collapsible-panel'][data-cl-closed] {
 height: 0;
}
```

27 changes: 27 additions & 0 deletions
packages/swingset/src/stories/collapsible.stories.tsx

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@@ -0,0 +1,27 @@
import { Collapsible } from '@clerk/headless/collapsible';

import type { StoryMeta } from '@/lib/types';

// Headless primitives ship no styles. This single demo renders the primitive raw —
// unstyled — so it faithfully reflects what `@clerk/headless` provides: behavior, state,
// and ARIA wiring via the `data-cl-*` attributes each part emits, with zero appearance.
// It is embedded once into the overview via `<Story>` in the MDX (the one thing prose
// can't convey: that it actually expands/collapses). There is no interactive knob canvas
// for headless primitives.

export const meta: StoryMeta = {
 group: 'Primitives',
 title: 'Collapsible',
};

export function Default() {
 return (
 <Collapsible.Root>
 <Collapsible.Trigger>What is a headless component?</Collapsible.Trigger>
 <Collapsible.Panel>
 A headless component provides behavior, state management, and accessibility without imposing any styles — you
 bring your own CSS via the <code>data-cl-slot</code> attributes it emits.
 </Collapsible.Panel>
 </Collapsible.Root>
 );
}

3 changes: 2 additions & 1 deletion
packages/swingset/tsconfig.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -13,7 +13,8 @@
 "paths": {
 "@/*": ["./src/*"],
 "@clerk/ui/mosaic": ["../ui/src/mosaic"],
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"]
 "@clerk/ui/mosaic/*": ["../ui/src/mosaic/*"],
 "@clerk/headless/*": ["../headless/src/primitives/*"]
 },
 "plugins": [
 {
Expand Down

3 changes: 3 additions & 0 deletions
pnpm-lock.yaml

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Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.


10 changes: 10 additions & 0 deletions
prettier.config.mjs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -9,4 +9,14 @@ export default {
 singleQuote: true,
 tabWidth: 2,
 trailingComma: 'all',
 overrides: [
 {
 // Leave fenced code samples in MDX docs exactly as authored. Without this,
 // `semi: true` reformats the embedded code and re-adds trailing semicolons to
 // JSX usage examples (e.g. `</Collapsible.Root>;`). Markdown prose and tables
 // are still formatted as normal.
 files: '*.mdx',
 options: { embeddedLanguageFormatting: 'off' },
 },
 ],
};
Loading