feat: improve typescript support for config file

docs/.vitepress/config.ts

@@ -1,4 +1,6 @@
-export default {
+import { defineConfig } from '../../src/node'
+
+export default defineConfig({
   lang: 'en-US',
   title: 'VitePress',
   description: 'Vite & Vue powered static site generator.',
@@ -42,7 +44,7 @@ export default {
       '/': getGuideSidebar()
     }
   }
-}
+})
 
 function getGuideSidebar() {
   return [

docs/guide/configuration.md

@@ -1,5 +1,7 @@
 # Configuration
 
+## Overview
+
 Without any configuration, the page is pretty minimal, and the user has no way to navigate around the site. To customize your site, let’s first create a `.vitepress` directory inside your docs directory. This is where all VitePress-specific files will be placed. Your project structure is probably like this:
 
 ```bash
@@ -21,3 +23,59 @@ module.exports = {
 ```
 
 Check out the [Config Reference](/config/basics) for a full list of options.
+
+
+## Config Intellisense
+
+Since VitePress ships with TypeScript typings, you can leverage your IDE's intellisense with jsdoc type hints:
+
+```js
+/**
+ * @type {import('vitepress').UserConfig}
+ */
+const config = {
+  // ...
+}
+
+export default config
+```
+
+Alternatively, you can use the `defineConfig` helper at which should provide intellisense without the need for jsdoc annotations:
+
+```js
+import { defineConfig } from 'vitepress'
+
+export default defineConfig({
+  // ...
+})
+```
+
+VitePress also directly supports TS config files. You can use `.vitepress/config.ts` with the `defineConfig` helper as well.
+
+
+## Typed Theme Config
+
+By default, `defineConfig` helper leverages the theme config type from default theme:
+
+```js
+import { defineConfig } from 'vitepress'
+
+export default defineConfig({
+  themeConfig: {
+     // Type is `DefaultTheme.Config` 
+  }
+})
+```
+
+If you use a custom theme, you'll be able to pass the generics type for your custom theme, and you need overload it with the second parameter of `defineConfig` helper:
+
+```js
+import { defineConfig } from 'vitepress'
+import { ThemeConfig } from 'your-theme'
+
+export default defineConfig<ThemeConfig>({
+  themeConfig: {
+    // Type is `ThemeConfig` 
+  }
+}, true); // declare `usingCustomTheme` and discard usage of the default theme.
+```

src/client/theme-default/config.ts

@@ -1,146 +1 @@
-export namespace DefaultTheme {
-  export interface Config {
-    logo?: string
-    nav?: NavItem[] | false
-    sidebar?: SideBarConfig | MultiSideBarConfig
-
-    /**
-     * GitHub repository following the format <user>/<project>.
-     *
-     * @example `"vuejs/vue-next"`
-     */
-    repo?: string
-
-    /**
-     * Customize the header label. Defaults to GitHub/Gitlab/Bitbucket
-     * depending on the provided repo.
-     *
-     * @example `"Contribute!"`
-     */
-    repoLabel?: string
-
-    /**
-     * If your docs are in a different repository from your main project.
-     *
-     * @example `"vuejs/docs-next"`
-     */
-    docsRepo?: string
-
-    /**
-     * If your docs are not at the root of the repo.
-     *
-     * @example `"docs"`
-     */
-    docsDir?: string
-
-    /**
-     * If your docs are in a different branch. Defaults to `master`.
-     *
-     * @example `"next"`
-     */
-    docsBranch?: string
-
-    /**
-     * Enable links to edit pages at the bottom of the page.
-     */
-    editLinks?: boolean
-
-    /**
-     * Custom text for edit link. Defaults to "Edit this page".
-     */
-    editLinkText?: string
-
-    /**
-     * Show last updated time at the bottom of the page. Defaults to `false`.
-     * If given a string, it will be displayed as a prefix (default value:
-     * "Last Updated").
-     */
-    lastUpdated?: string | boolean
-
-    prevLinks?: boolean
-    nextLinks?: boolean
-
-    locales?: Record<string, LocaleConfig & Omit<Config, 'locales'>>
-
-    algolia?: AlgoliaSearchOptions
-
-    carbonAds?: {
-      carbon: string
-      custom?: string
-      placement: string
-    }
-  }
-
-  // navbar --------------------------------------------------------------------
-
-  export type NavItem = NavItemWithLink | NavItemWithChildren
-
-  export interface NavItemBase {
-    text: string
-    target?: string
-    rel?: string
-    ariaLabel?: string
-    activeMatch?: string
-  }
-
-  export interface NavItemWithLink extends NavItemBase {
-    link: string
-  }
-
-  export interface NavItemWithChildren extends NavItemBase {
-    items: NavItemWithLink[]
-  }
-
-  // sidebar -------------------------------------------------------------------
-
-  export type SideBarConfig = SideBarItem[] | 'auto' | false
-
-  export interface MultiSideBarConfig {
-    [path: string]: SideBarConfig
-  }
-
-  export type SideBarItem = SideBarLink | SideBarGroup
-
-  export interface SideBarLink {
-    text: string
-    link: string
-  }
-
-  export interface SideBarGroup {
-    text: string
-    link?: string
-
-    /**
-     * @default false
-     */
-    collapsable?: boolean
-
-    children: SideBarItem[]
-  }
-
-  // algolia  ------------------------------------------------------------------
-  // partially copied from @docsearch/react/dist/esm/DocSearch.d.ts
-  export interface AlgoliaSearchOptions {
-    appId?: string
-    apiKey: string
-    indexName: string
-    placeholder?: string
-    searchParameters?: any
-    disableUserPersonalization?: boolean
-    initialQuery?: string
-  }
-
-  // locales -------------------------------------------------------------------
-
-  export interface LocaleConfig {
-    /**
-     * Text for the language dropdown.
-     */
-    selectText?: string
-
-    /**
-     * Label for this locale in the language dropdown.
-     */
-    label?: string
-  }
-}
+export { DefaultTheme } from '../shared'

src/client/theme-default/index.ts

@@ -8,6 +8,7 @@ import { Theme } from 'vitepress'
 import Layout from './Layout.vue'
 import NotFound from './NotFound.vue'
 
+export { DefaultTheme } from './config'
 const theme: Theme = {
   Layout,
   NotFound

src/client/tsconfig.json

@@ -12,5 +12,5 @@
       "vitepress": ["index.ts"]
     }
   },
-  "include": [".", "../../types/shared.d.ts"]
+  "include": ["."]
 }

src/node/config.ts

@@ -14,7 +14,8 @@ import {
   SiteData,
   HeadConfig,
   LocaleConfig,
-  createLangDictionary
+  createLangDictionary,
+  DefaultTheme,
 } from './shared'
 import { resolveAliases, APP_PATH, DEFAULT_THEME_PATH } from './alias'
 import { MarkdownOptions } from './markdown/markdown'
@@ -26,14 +27,16 @@ const debug = _debug('vitepress:config')
 
 export type { MarkdownOptions }
 
-export interface UserConfig<ThemeConfig = any> {
-  extends?: RawConfigExports
+export type ThemeConfig = any;
+
+export interface UserConfig<T extends ThemeConfig = ThemeConfig> {
+  extends?: RawConfigExports<T>
   lang?: string
   base?: string
   title?: string
   description?: string
   head?: HeadConfig[]
-  themeConfig?: ThemeConfig
+  themeConfig?: T
   locales?: Record<string, LocaleConfig>
   markdown?: MarkdownOptions
   /**
@@ -55,15 +58,15 @@ export interface UserConfig<ThemeConfig = any> {
   mpa?: boolean
 }
 
-export type RawConfigExports =
-  | UserConfig
-  | Promise<UserConfig>
-  | (() => UserConfig | Promise<UserConfig>)
+export type RawConfigExports<T extends ThemeConfig = ThemeConfig> =
+  | UserConfig<T>
+  | Promise<UserConfig<T>>
+  | (() => UserConfig<T> | Promise<UserConfig<T>>)
 
-export interface SiteConfig<ThemeConfig = any> {
+export interface SiteConfig<T = ThemeConfig> {
   root: string
   srcDir: string
-  site: SiteData<ThemeConfig>
+  site: SiteData<T>
   configPath: string | undefined
   themeDir: string
   outDir: string
@@ -82,7 +85,12 @@ const resolve = (root: string, file: string) =>
 /**
  * Type config helper
  */
-export function defineConfig(config: RawConfigExports) {
+ export function defineConfig<T extends ThemeConfig = ThemeConfig>(
+  config: UserConfig<T>,
+  usingCustomTheme: true
+): void
+export function defineConfig(config: UserConfig<DefaultTheme.Config>): void
+export function defineConfig(config: ThemeConfig) {
   return config
 }
 
@@ -150,7 +158,7 @@ async function resolveUserConfig(
     }
   }
 
-  const userConfig: RawConfigExports = configPath
+  const userConfig: RawConfigExports<ThemeConfig> = configPath
     ? ((
         await loadConfigFromFile(
           {
@@ -173,7 +181,7 @@ async function resolveUserConfig(
 }
 
 async function resolveConfigExtends(
-  config: RawConfigExports
+  config: RawConfigExports<ThemeConfig>
 ): Promise<UserConfig> {
   const resolved = await (typeof config === 'function' ? config() : config)
   if (resolved.extends) {

src/node/index.ts

@@ -4,4 +4,4 @@ export * from './serve/serve'
 export * from './config'
 export * from './markdown/markdown'
 
-export type { SiteData, HeadConfig, LocaleConfig } from '../../types/shared'
+export type { SiteData, HeadConfig, LocaleConfig, DefaultTheme } from '../../types/shared'

src/shared/shared.ts

@@ -5,7 +5,8 @@ export type {
   PageData,
   HeadConfig,
   LocaleConfig,
-  Header
+  Header,
+  DefaultTheme,
 } from '../../types/shared'
 
 export const EXTERNAL_URL_RE = /^https?:/i

src/shared/tsconfig.json

@@ -3,5 +3,5 @@
   "compilerOptions": {
     "baseUrl": "."
   },
-  "include": [".", "../../types/shared.d.ts"]
+  "include": ["."]
 }

types/default-theme.d.ts

@@ -0,0 +1,146 @@
+export namespace DefaultTheme {
+  export interface Config {
+    logo?: string
+    nav?: NavItem[] | false
+    sidebar?: SideBarConfig | MultiSideBarConfig
+
+    /**
+     * GitHub repository following the format <user>/<project>.
+     *
+     * @example `"vuejs/vue-next"`
+     */
+    repo?: string
+
+    /**
+     * Customize the header label. Defaults to GitHub/Gitlab/Bitbucket
+     * depending on the provided repo.
+     *
+     * @example `"Contribute!"`
+     */
+    repoLabel?: string
+
+    /**
+     * If your docs are in a different repository from your main project.
+     *
+     * @example `"vuejs/docs-next"`
+     */
+    docsRepo?: string
+
+    /**
+     * If your docs are not at the root of the repo.
+     *
+     * @example `"docs"`
+     */
+    docsDir?: string
+
+    /**
+     * If your docs are in a different branch. Defaults to `master`.
+     *
+     * @example `"next"`
+     */
+    docsBranch?: string
+
+    /**
+     * Enable links to edit pages at the bottom of the page.
+     */
+    editLinks?: boolean
+
+    /**
+     * Custom text for edit link. Defaults to "Edit this page".
+     */
+    editLinkText?: string
+
+    /**
+     * Show last updated time at the bottom of the page. Defaults to `false`.
+     * If given a string, it will be displayed as a prefix (default value:
+     * "Last Updated").
+     */
+    lastUpdated?: string | boolean
+
+    prevLinks?: boolean
+    nextLinks?: boolean
+
+    locales?: Record<string, LocaleConfig & Omit<Config, 'locales'>>
+
+    algolia?: AlgoliaSearchOptions
+
+    carbonAds?: {
+      carbon: string
+      custom?: string
+      placement: string
+    }
+  }
+
+  // navbar --------------------------------------------------------------------
+
+  export type NavItem = NavItemWithLink | NavItemWithChildren
+
+  export interface NavItemBase {
+    text: string
+    target?: string
+    rel?: string
+    ariaLabel?: string
+    activeMatch?: string
+  }
+
+  export interface NavItemWithLink extends NavItemBase {
+    link: string
+  }
+
+  export interface NavItemWithChildren extends NavItemBase {
+    items: NavItemWithLink[]
+  }
+
+  // sidebar -------------------------------------------------------------------
+
+  export type SideBarConfig = SideBarItem[] | 'auto' | false
+
+  export interface MultiSideBarConfig {
+    [path: string]: SideBarConfig
+  }
+
+  export type SideBarItem = SideBarLink | SideBarGroup
+
+  export interface SideBarLink {
+    text: string
+    link: string
+  }
+
+  export interface SideBarGroup {
+    text: string
+    link?: string
+
+    /**
+     * @default false
+     */
+    collapsable?: boolean
+
+    children: SideBarItem[]
+  }
+
+  // algolia  ------------------------------------------------------------------
+  // partially copied from @docsearch/react/dist/esm/DocSearch.d.ts
+  export interface AlgoliaSearchOptions {
+    appId?: string
+    apiKey: string
+    indexName: string
+    placeholder?: string
+    searchParameters?: any
+    disableUserPersonalization?: boolean
+    initialQuery?: string
+  }
+
+  // locales -------------------------------------------------------------------
+
+  export interface LocaleConfig {
+    /**
+     * Text for the language dropdown.
+     */
+    selectText?: string
+
+    /**
+     * Label for this locale in the language dropdown.
+     */
+    label?: string
+  }
+}

types/index.d.ts

@@ -1,4 +1,4 @@
 export * from './shared'
+export * from './default-theme'
 export * from '../dist/node/index'
 export * from '../dist/client/index'
-export * from '../dist/client/theme-default/config'

types/shared.d.ts

@@ -1,5 +1,7 @@
 // types shared between server and client
 
+export { DefaultTheme } from './default-theme'
+
 export interface LocaleConfig {
   lang: string
   title?: string
@@ -9,7 +11,7 @@ export interface LocaleConfig {
   selectText?: string
 }
 
-export interface SiteData<ThemeConfig = any> {
+export interface SiteData<T = any> {
   base: string
   /**
    * Language of the site as it should be set on the `html` element.
@@ -19,7 +21,7 @@ export interface SiteData<ThemeConfig = any> {
   title: string
   description: string
   head: HeadConfig[]
-  themeConfig: ThemeConfig
+  themeConfig: T
   locales: Record<string, LocaleConfig>
   /**
    * Available locales for the site when it has defined `locales` in its