Files
ComfyUI_frontend/apps/desktop-ui/.storybook/main.ts
Jin Yi e9b641cfb7 [bugfix] Fix Storybook _sfc_main undefined error after v1.29.3 (#6635)
## Summary

Fixes Storybook rendering issue where all components fail to load with
`_sfc_main is not defined` error in **local development** since v1.29.3.

## Problem

After upgrading to v1.29.3, all Storybook components fail to render **in
local development** (`pnpm storybook`) with the following error:

```
ReferenceError: _sfc_main is not defined
The component failed to render properly, likely due to a configuration issue in Storybook.
```

**Important**: This issue only affects **local development**
environments. The deployed/built Storybook works correctly.

This affects both:
- Main Storybook (`pnpm storybook`)
- Desktop-ui Storybook instances

## Root Cause

In v1.29.3, commit `64430708e` ("perf: tree shaking and minify #6068")
enabled build optimizations in `vite.config.mts`:

```typescript
// Before (v1.29.2)
rollupOptions: {
  treeshake: false
}
esbuild: {
  minifyIdentifiers: false
}

// After (v1.29.3)
rollupOptions: {
  treeshake: true  // ⚠️ Enabled
}
esbuild: {
  minifyIdentifiers: SHOULD_MINIFY  // ⚠️ Conditionally enabled
}
```

While these optimizations are beneficial for production builds, they
cause issues in **Storybook's local dev server**:

1. **Tree-shaking in dev mode**: Rollup incorrectly identifies Vue SFC's
`_sfc_main` exports as unused code during the dev server's module
transformation
2. **Identifier minification**: esbuild minifies `_sfc_main` to shorter
names in development, breaking Storybook's HMR (Hot Module Replacement)
and dynamic module loading

Since Storybook's `main.ts` inherits settings from `vite.config.mts` via
`mergeConfig`, these optimizations were applied to Storybook's dev
server configuration, causing Vue components to fail rendering in local
development.

**Why deployed Storybook works**: Production builds have different
optimization pipelines that handle Vue SFCs correctly, but the dev
server's real-time transformation breaks with these settings.

## Solution

Added explicit build configuration overrides in both Storybook
configurations to ensure the **dev server** doesn't inherit problematic
optimizations:

**Files changed:**
- `.storybook/main.ts`
- `apps/desktop-ui/.storybook/main.ts`

**Changes:**
```typescript
esbuild: {
  // Prevent minification of identifiers to preserve _sfc_main in dev mode
  minifyIdentifiers: false,
  keepNames: true
},
build: {
  rollupOptions: {
    // Disable tree-shaking for Storybook dev server to prevent Vue SFC exports from being removed
    treeshake: false,
    // ... existing onwarn config
  }
}
```

This ensures Storybook's **local development server** prioritizes
stability and debuggability over bundle size optimization, while
production builds continue to benefit from tree-shaking and
minification.

## Testing

1. Cleared Storybook and Vite caches: `rm -rf .storybook/.cache
node_modules/.vite`
2. Started local Storybook dev server with `pnpm storybook`
3. Verified all component stories render correctly without `_sfc_main`
errors
4. Ran `pnpm typecheck` to ensure TypeScript compilation succeeds
5. Tested HMR (Hot Module Replacement) works correctly with component
changes

## Context

- This is a **local development-only** issue; deployed Storybook builds
work fine
- Storybook dev server requires special handling because it dynamically
imports and hot-reloads all stories at runtime
- Vue SFC compilation generates `_sfc_main` as an internal identifier
that must be preserved during dev transformations
- Development tools like Storybook benefit from unoptimized builds for
better debugging, HMR, and stability
- Production builds remain optimized with tree-shaking and minification
enabled

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6635-bugfix-Fix-Storybook-_sfc_main-undefined-error-after-v1-29-3-2a56d73d36508194a25eef56789e5e2b)
by [Unito](https://www.unito.io)
2025-11-08 10:40:33 -07:00

111 lines
3.4 KiB
TypeScript

import type { StorybookConfig } from '@storybook/vue3-vite'
import { FileSystemIconLoader } from 'unplugin-icons/loaders'
import IconsResolver from 'unplugin-icons/resolver'
import Icons from 'unplugin-icons/vite'
import Components from 'unplugin-vue-components/vite'
import type { InlineConfig } from 'vite'
const config: StorybookConfig = {
stories: ['../src/**/*.stories.@(js|jsx|mjs|ts|tsx)'],
addons: ['@storybook/addon-docs'],
framework: {
name: '@storybook/vue3-vite',
options: {}
},
staticDirs: [{ from: '../public', to: '/' }],
async viteFinal(config) {
// Use dynamic import to avoid CJS deprecation warning
const { mergeConfig } = await import('vite')
const { default: tailwindcss } = await import('@tailwindcss/vite')
// Filter out any plugins that might generate import maps
if (config.plugins) {
config.plugins = config.plugins
// Type guard: ensure we have valid plugin objects with names
.filter(
(plugin): plugin is NonNullable<typeof plugin> & { name: string } => {
return (
plugin !== null &&
plugin !== undefined &&
typeof plugin === 'object' &&
'name' in plugin &&
typeof plugin.name === 'string'
)
}
)
// Business logic: filter out import-map plugins
.filter((plugin) => !plugin.name.includes('import-map'))
}
return mergeConfig(config, {
// Replace plugins entirely to avoid inheritance issues
plugins: [
// Only include plugins we explicitly need for Storybook
tailwindcss(),
Icons({
compiler: 'vue3',
customCollections: {
comfy: FileSystemIconLoader(
process.cwd() + '/../../packages/design-system/src/icons'
)
}
}),
Components({
dts: false, // Disable dts generation in Storybook
resolvers: [
IconsResolver({
customCollections: ['comfy']
})
],
dirs: [
process.cwd() + '/src/components',
process.cwd() + '/src/views'
],
deep: true,
extensions: ['vue'],
directoryAsNamespace: true
})
],
server: {
allowedHosts: true
},
resolve: {
alias: {
'@': process.cwd() + '/src',
'@frontend-locales': process.cwd() + '/../../src/locales'
}
},
esbuild: {
// Prevent minification of identifiers to preserve _sfc_main
minifyIdentifiers: false,
keepNames: true
},
build: {
rollupOptions: {
// Disable tree-shaking for Storybook to prevent Vue SFC exports from being removed
treeshake: false,
onwarn: (warning, warn) => {
// Suppress specific warnings
if (
warning.code === 'UNUSED_EXTERNAL_IMPORT' &&
warning.message?.includes('resolveComponent')
) {
return
}
// Suppress Storybook font asset warnings
if (
warning.code === 'UNRESOLVED_IMPORT' &&
warning.message?.includes('nunito-sans')
) {
return
}
warn(warning)
}
},
chunkSizeWarningLimit: 1000
}
} satisfies InlineConfig)
}
}
export default config