From f8672ed70c3bcbb9a4f9863bbc7282148a2ca4d1 Mon Sep 17 00:00:00 2001
From: Shigma <1700011071@pku.edu.cn>
Date: Tue, 5 Mar 2019 14:18:59 +0800
Subject: [PATCH 1/5] pascalize component name

---
 packages/@vuepress/core/lib/client/util.js         | 14 ++++++++++----
 .../lib/node/internal-plugins/layoutComponents.js  |  4 +++-
 packages/@vuepress/shared-utils/src/index.ts       |  2 ++
 packages/@vuepress/shared-utils/src/pascalize.ts   |  3 +++
 4 files changed, 18 insertions(+), 5 deletions(-)
 create mode 100644 packages/@vuepress/shared-utils/src/pascalize.ts

diff --git a/packages/@vuepress/core/lib/client/util.js b/packages/@vuepress/core/lib/client/util.js
index e4e483f47b..e2f8eac200 100644
--- a/packages/@vuepress/core/lib/client/util.js
+++ b/packages/@vuepress/core/lib/client/util.js
@@ -4,6 +4,11 @@ import pageComponents from '@internal/page-components'
 
 const asyncComponents = Object.assign({}, layoutComponents, pageComponents)
 
+// TODO: reuse this function in shared-utils
+function pascalize (source = '') {
+  return source.replace(/(^|-)[a-z]/g, s => s.slice(-1).toUpperCase())
+}
+
 export function isPageExists (pageKey) {
   return Boolean(pageComponents[pageKey])
 }
@@ -17,7 +22,7 @@ export function getPageAsyncComponent (pageKey) {
 }
 
 export function isLayoutExists (layout) {
-  return Boolean(layoutComponents[layout])
+  return Boolean(getLayoutAsyncComponent(layout))
 }
 
 export function isLayoutLoaded (layout) {
@@ -25,11 +30,12 @@ export function isLayoutLoaded (layout) {
 }
 
 export function getLayoutAsyncComponent (pageKey) {
-  return layoutComponents[pageKey]
+  return layoutComponents[pascalize(pageKey)]
 }
 
 export function ensureAsyncComponentsLoaded (...names) {
   return Promise.all(names.filter(v => v).map(async (name) => {
+    name = pascalize(name)
     if (!Vue.component(name) && asyncComponents[name]) {
       const comp = await asyncComponents[name]()
       Vue.component(name, comp.default)
@@ -96,7 +102,7 @@ export function findPageByKey (pages, key) {
  *
  *
  * Usage:
- *
+ * ```js
  * import { normalizeConfig } from '@app/util'
  * export default {
  *   data () {
@@ -108,7 +114,7 @@ export function findPageByKey (pages, key) {
  *     }
  *   }
  * }
- *
+ * ```
  *
  * e.g.
  *
diff --git a/packages/@vuepress/core/lib/node/internal-plugins/layoutComponents.js b/packages/@vuepress/core/lib/node/internal-plugins/layoutComponents.js
index d8b71a2417..a17c4daf21 100644
--- a/packages/@vuepress/core/lib/node/internal-plugins/layoutComponents.js
+++ b/packages/@vuepress/core/lib/node/internal-plugins/layoutComponents.js
@@ -1,3 +1,5 @@
+const { pascalize } = require('@vuepress/shared-utils')
+
 module.exports = (options, ctx) => {
   return {
     name: '@vuepress/internal-layout-components',
@@ -5,7 +7,7 @@ module.exports = (options, ctx) => {
     async clientDynamicModules () {
       const componentNames = Object.keys(ctx.themeAPI.layoutComponentMap)
       const code = `export default {\n${componentNames
-        .map(name => `  ${JSON.stringify(name)}: () => import(${JSON.stringify(ctx.themeAPI.layoutComponentMap[name].path)})`)
+        .map(name => `  ${JSON.stringify(pascalize(name))}: () => import(${JSON.stringify(ctx.themeAPI.layoutComponentMap[name].path)})`)
         .join(',\n')} \n}`
       return { name: 'layout-components.js', content: code, dirname: 'internal' }
     }
diff --git a/packages/@vuepress/shared-utils/src/index.ts b/packages/@vuepress/shared-utils/src/index.ts
index 689300274e..df7c1a4df6 100644
--- a/packages/@vuepress/shared-utils/src/index.ts
+++ b/packages/@vuepress/shared-utils/src/index.ts
@@ -18,6 +18,7 @@ import * as parseEmojis from './parseEmojis'
 import parseFrontmatter from './parseFrontmatter'
 import parseHeaders from './parseHeaders'
 import * as parseVueFrontmatter from './parseVueFrontmatter'
+import pascalize from './pascalize'
 import performance from './performance'
 import slugify from './slugify'
 import sort from './sort'
@@ -54,6 +55,7 @@ export {
   parseFrontmatter,
   parseHeaders,
   parseVueFrontmatter,
+  pascalize,
   performance,
   slugify,
   sort,
diff --git a/packages/@vuepress/shared-utils/src/pascalize.ts b/packages/@vuepress/shared-utils/src/pascalize.ts
new file mode 100644
index 0000000000..0c7a2f695c
--- /dev/null
+++ b/packages/@vuepress/shared-utils/src/pascalize.ts
@@ -0,0 +1,3 @@
+export default function pascalize (source: string) {
+  return source.replace(/(^|-)[a-z]/g, s => s.slice(-1).toUpperCase())
+}

From 61d1c8ea0ad82acd8c080dcce7918c1a52411811 Mon Sep 17 00:00:00 2001
From: Shigma <1700011071@pku.edu.cn>
Date: Wed, 6 Mar 2019 16:28:08 +0800
Subject: [PATCH 2/5] pascalize page key

---
 packages/@vuepress/core/lib/client/util.js                    | 4 ++--
 .../core/lib/node/internal-plugins/pageComponents.js          | 4 +++-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/packages/@vuepress/core/lib/client/util.js b/packages/@vuepress/core/lib/client/util.js
index e2f8eac200..f39c52f9f0 100644
--- a/packages/@vuepress/core/lib/client/util.js
+++ b/packages/@vuepress/core/lib/client/util.js
@@ -6,7 +6,7 @@ const asyncComponents = Object.assign({}, layoutComponents, pageComponents)
 
 // TODO: reuse this function in shared-utils
 function pascalize (source = '') {
-  return source.replace(/(^|-)[a-z]/g, s => s.slice(-1).toUpperCase())
+  return source.replace(/(^|-)\w/g, s => s.slice(-1).toUpperCase())
 }
 
 export function isPageExists (pageKey) {
@@ -18,7 +18,7 @@ export function isPageLoaded (pageKey) {
 }
 
 export function getPageAsyncComponent (pageKey) {
-  return pageComponents[pageKey]
+  return pageComponents[pascalize(pageKey)]
 }
 
 export function isLayoutExists (layout) {
diff --git a/packages/@vuepress/core/lib/node/internal-plugins/pageComponents.js b/packages/@vuepress/core/lib/node/internal-plugins/pageComponents.js
index e4f1377888..ce190db599 100644
--- a/packages/@vuepress/core/lib/node/internal-plugins/pageComponents.js
+++ b/packages/@vuepress/core/lib/node/internal-plugins/pageComponents.js
@@ -1,3 +1,5 @@
+const { pascalize } = require('@vuepress/shared-utils')
+
 module.exports = (options, ctx) => {
   const { pages } = ctx
   // const componentNames = Object.keys(layoutComponentMap)
@@ -8,7 +10,7 @@ module.exports = (options, ctx) => {
     async clientDynamicModules () {
       const code = `export default {\n${pages
         .filter(({ _filePath }) => _filePath)
-        .map(({ key, _filePath }) => `  ${JSON.stringify(key)}: () => import(${JSON.stringify(_filePath)})`)
+        .map(({ key, _filePath }) => `  ${JSON.stringify(pascalize(key))}: () => import(${JSON.stringify(_filePath)})`)
         .join(',\n')} \n}`
       return { name: 'page-components.js', content: code, dirname: 'internal' }
     }

From 961b0ab7213c51e49d143625bdf86d9166bfd057 Mon Sep 17 00:00:00 2001
From: Shigma <1700011071@pku.edu.cn>
Date: Wed, 6 Mar 2019 16:41:54 +0800
Subject: [PATCH 3/5] fix

---
 packages/@vuepress/core/lib/client/util.js       | 2 +-
 packages/@vuepress/shared-utils/src/pascalize.ts | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/@vuepress/core/lib/client/util.js b/packages/@vuepress/core/lib/client/util.js
index f39c52f9f0..8a8f552e98 100644
--- a/packages/@vuepress/core/lib/client/util.js
+++ b/packages/@vuepress/core/lib/client/util.js
@@ -10,7 +10,7 @@ function pascalize (source = '') {
 }
 
 export function isPageExists (pageKey) {
-  return Boolean(pageComponents[pageKey])
+  return Boolean(getPageAsyncComponent(pageKey))
 }
 
 export function isPageLoaded (pageKey) {
diff --git a/packages/@vuepress/shared-utils/src/pascalize.ts b/packages/@vuepress/shared-utils/src/pascalize.ts
index 0c7a2f695c..21aa2caf5f 100644
--- a/packages/@vuepress/shared-utils/src/pascalize.ts
+++ b/packages/@vuepress/shared-utils/src/pascalize.ts
@@ -1,3 +1,3 @@
 export default function pascalize (source: string) {
-  return source.replace(/(^|-)[a-z]/g, s => s.slice(-1).toUpperCase())
+  return source.replace(/(^|-)\w/g, s => s.slice(-1).toUpperCase())
 }

From 4641f35ee95eb060c5e07b7c2ae550935bb94741 Mon Sep 17 00:00:00 2001
From: meteorlxy <meteor.lxy@foxmail.com>
Date: Wed, 6 Mar 2019 18:40:42 +0800
Subject: [PATCH 4/5] refactor($core): auto register layouts and pages (for
 #1402) (#1409)

---
 packages/@vuepress/core/lib/client/app.js     |  7 +--
 .../core/lib/client/components/Content.js     |  4 +-
 .../core/lib/client/plugins/VuePress.d.ts     |  8 +---
 .../core/lib/client/plugins/VuePress.js       | 39 +++++++++-------
 packages/@vuepress/core/lib/client/util.js    | 45 -------------------
 .../node/internal-plugins/layoutComponents.js | 13 +++---
 .../node/internal-plugins/pageComponents.js   | 13 +++---
 .../core/lib/node/internal-plugins/routes.js  |  5 +--
 8 files changed, 42 insertions(+), 92 deletions(-)

diff --git a/packages/@vuepress/core/lib/client/app.js b/packages/@vuepress/core/lib/client/app.js
index bcccec1797..a98c4afb71 100644
--- a/packages/@vuepress/core/lib/client/app.js
+++ b/packages/@vuepress/core/lib/client/app.js
@@ -9,14 +9,12 @@ import globalUIComponents from '@internal/global-ui'
 import ClientComputedMixin from '@transform/ClientComputedMixin'
 import VuePress from './plugins/VuePress'
 import { handleRedirectForCleanUrls } from './redirect.js'
-import { getLayoutAsyncComponent } from './util'
 
 // built-in components
 import Content from './components/Content.js'
 import ContentSlotsDistributor from './components/ContentSlotsDistributor'
 import OutboundLink from './components/OutboundLink.vue'
 import ClientOnly from './components/ClientOnly'
-import TOC from './components/TOC.vue'
 
 // suggest dev server restart on base change
 if (module.hot) {
@@ -44,11 +42,8 @@ Vue.component('ContentSlotsDistributor', ContentSlotsDistributor)
 Vue.component('OutboundLink', OutboundLink)
 // component for client-only content
 Vue.component('ClientOnly', ClientOnly)
-// core components
-Vue.component('Layout', getLayoutAsyncComponent('Layout'))
-Vue.component('NotFound', getLayoutAsyncComponent('NotFound'))
 // markdown components
-Vue.component('TOC', TOC)
+Vue.component('TOC', () => import('./components/TOC.vue'))
 
 // global helper for adding base path to absolute urls
 Vue.prototype.$withBase = function (path) {
diff --git a/packages/@vuepress/core/lib/client/components/Content.js b/packages/@vuepress/core/lib/client/components/Content.js
index c2ed88d487..b4811acf72 100644
--- a/packages/@vuepress/core/lib/client/components/Content.js
+++ b/packages/@vuepress/core/lib/client/components/Content.js
@@ -1,5 +1,3 @@
-import { isPageExists } from '../util'
-
 export default {
   props: {
     pageKey: String,
@@ -10,7 +8,7 @@ export default {
   },
   render (h) {
     const pageKey = this.pageKey || this.$parent.$page.key
-    if (isPageExists(pageKey)) {
+    if (this.$vuepress.isPageExists(pageKey)) {
       return h(pageKey)
     }
     return h('')
diff --git a/packages/@vuepress/core/lib/client/plugins/VuePress.d.ts b/packages/@vuepress/core/lib/client/plugins/VuePress.d.ts
index ef4cf3782f..48af0be18c 100644
--- a/packages/@vuepress/core/lib/client/plugins/VuePress.d.ts
+++ b/packages/@vuepress/core/lib/client/plugins/VuePress.d.ts
@@ -4,13 +4,7 @@ import { AsyncComponent } from 'vue'
 declare class VuePress extends Store {
   isPageExists (pageKey: string): boolean;
 
-  isPageLoaded (pageKey: string): boolean;
-
-  getPageAsyncComponent (pageKey: string): () => Promise<AsyncComponent>;
-
-  loadPageAsyncComponent (pageKey: string): Promise<AsyncComponent>;
-
-  registerPageAsyncComponent (pageKey: string): void;
+  isLayoutExists (pageKey: string): boolean;
 }
 
 declare module "vue/types/vue" {
diff --git a/packages/@vuepress/core/lib/client/plugins/VuePress.js b/packages/@vuepress/core/lib/client/plugins/VuePress.js
index bdb93e1b54..c5043b3138 100644
--- a/packages/@vuepress/core/lib/client/plugins/VuePress.js
+++ b/packages/@vuepress/core/lib/client/plugins/VuePress.js
@@ -1,23 +1,28 @@
+import Vue from 'vue'
 import Store from './Store'
-import {
-  isPageExists,
-  isPageLoaded,
-  getPageAsyncComponent,
-  isLayoutExists,
-  isLayoutLoaded,
-  getLayoutAsyncComponent
-} from '../util'
 
-class VuePress extends Store {}
+// TODO: reuse this function in shared-utils
+function cached (fn) {
+  const cache = Object.create(null)
+  return str => {
+    if (typeof cache[str] === 'undefined') {
+      cache[str] = fn(str)
+    }
+    return cache[str]
+  }
+}
 
-Object.assign(VuePress.prototype, {
-  isPageExists,
-  isPageLoaded,
-  getPageAsyncComponent,
-  isLayoutExists,
-  isLayoutLoaded,
-  getLayoutAsyncComponent
-})
+const pascalize = cached((str = '') => str.replace(/(^|-)\w/g, s => s.slice(-1).toUpperCase()))
+
+class VuePress extends Store {
+  isPageExists (pageKey) {
+    return Boolean(Vue.component(pascalize(pageKey)))
+  }
+
+  isLayoutExists (layout) {
+    return Boolean(Vue.component(pascalize(layout)))
+  }
+}
 
 export default {
   install (Vue) {
diff --git a/packages/@vuepress/core/lib/client/util.js b/packages/@vuepress/core/lib/client/util.js
index 8a8f552e98..5094b3dc9e 100644
--- a/packages/@vuepress/core/lib/client/util.js
+++ b/packages/@vuepress/core/lib/client/util.js
@@ -1,48 +1,3 @@
-import Vue from 'vue'
-import layoutComponents from '@internal/layout-components'
-import pageComponents from '@internal/page-components'
-
-const asyncComponents = Object.assign({}, layoutComponents, pageComponents)
-
-// TODO: reuse this function in shared-utils
-function pascalize (source = '') {
-  return source.replace(/(^|-)\w/g, s => s.slice(-1).toUpperCase())
-}
-
-export function isPageExists (pageKey) {
-  return Boolean(getPageAsyncComponent(pageKey))
-}
-
-export function isPageLoaded (pageKey) {
-  return Boolean(Vue.component(pageKey))
-}
-
-export function getPageAsyncComponent (pageKey) {
-  return pageComponents[pascalize(pageKey)]
-}
-
-export function isLayoutExists (layout) {
-  return Boolean(getLayoutAsyncComponent(layout))
-}
-
-export function isLayoutLoaded (layout) {
-  return Boolean(Vue.component(layout))
-}
-
-export function getLayoutAsyncComponent (pageKey) {
-  return layoutComponents[pascalize(pageKey)]
-}
-
-export function ensureAsyncComponentsLoaded (...names) {
-  return Promise.all(names.filter(v => v).map(async (name) => {
-    name = pascalize(name)
-    if (!Vue.component(name) && asyncComponents[name]) {
-      const comp = await asyncComponents[name]()
-      Vue.component(name, comp.default)
-    }
-  }))
-}
-
 /**
  * Inject option to Vue SFC
  * @param {object} options
diff --git a/packages/@vuepress/core/lib/node/internal-plugins/layoutComponents.js b/packages/@vuepress/core/lib/node/internal-plugins/layoutComponents.js
index a17c4daf21..60ad57bcd2 100644
--- a/packages/@vuepress/core/lib/node/internal-plugins/layoutComponents.js
+++ b/packages/@vuepress/core/lib/node/internal-plugins/layoutComponents.js
@@ -4,12 +4,15 @@ module.exports = (options, ctx) => {
   return {
     name: '@vuepress/internal-layout-components',
 
-    async clientDynamicModules () {
+    async enhanceAppFiles () {
       const componentNames = Object.keys(ctx.themeAPI.layoutComponentMap)
-      const code = `export default {\n${componentNames
-        .map(name => `  ${JSON.stringify(pascalize(name))}: () => import(${JSON.stringify(ctx.themeAPI.layoutComponentMap[name].path)})`)
-        .join(',\n')} \n}`
-      return { name: 'layout-components.js', content: code, dirname: 'internal' }
+      const code = `import Vue from 'vue'\n${componentNames
+        .map(name => `Vue.component(${JSON.stringify(pascalize(name))}, () => import(${JSON.stringify(ctx.themeAPI.layoutComponentMap[name].path)}))`)
+        .join(',\n')} \n`
+      return {
+        name: 'layout-components.js',
+        content: code
+      }
     }
   }
 }
diff --git a/packages/@vuepress/core/lib/node/internal-plugins/pageComponents.js b/packages/@vuepress/core/lib/node/internal-plugins/pageComponents.js
index ce190db599..022fc2fdc5 100644
--- a/packages/@vuepress/core/lib/node/internal-plugins/pageComponents.js
+++ b/packages/@vuepress/core/lib/node/internal-plugins/pageComponents.js
@@ -7,12 +7,15 @@ module.exports = (options, ctx) => {
   return {
     name: '@vuepress/internal-page-components',
 
-    async clientDynamicModules () {
-      const code = `export default {\n${pages
+    async enhanceAppFiles () {
+      const code = `import Vue from 'vue'\n${pages
         .filter(({ _filePath }) => _filePath)
-        .map(({ key, _filePath }) => `  ${JSON.stringify(pascalize(key))}: () => import(${JSON.stringify(_filePath)})`)
-        .join(',\n')} \n}`
-      return { name: 'page-components.js', content: code, dirname: 'internal' }
+        .map(({ key, _filePath }) => `Vue.component(${JSON.stringify(pascalize(key))}, () => import(${JSON.stringify(_filePath)}))`)
+        .join(',\n')} \n`
+      return {
+        name: 'page-components.js',
+        content: code
+      }
     }
   }
 }
diff --git a/packages/@vuepress/core/lib/node/internal-plugins/routes.js b/packages/@vuepress/core/lib/node/internal-plugins/routes.js
index d6cf90b9b1..8c91601c00 100644
--- a/packages/@vuepress/core/lib/node/internal-plugins/routes.js
+++ b/packages/@vuepress/core/lib/node/internal-plugins/routes.js
@@ -42,10 +42,7 @@ function routesCode (pages) {
   {
     name: ${JSON.stringify(componentName)},
     path: ${JSON.stringify(pagePath)},
-    component: GlobalLayout,
-    beforeEnter: (to, from, next) => {
-      ensureAsyncComponentsLoaded(${JSON.stringify(layout || 'Layout')}, ${JSON.stringify(componentName)}).then(next)
-    },${_meta ? `\n    meta: ${JSON.stringify(_meta)}` : ''}
+    component: GlobalLayout,${_meta ? `\n    meta: ${JSON.stringify(_meta)}` : ''}
   }`
 
     const dncodedPath = decodeURIComponent(pagePath)

From 65a27410d5e312a8f66dceea79d9eee265340079 Mon Sep 17 00:00:00 2001
From: Shigma <1700011071@pku.edu.cn>
Date: Wed, 6 Mar 2019 19:23:52 +0800
Subject: [PATCH 5/5] refactor: integrate isLayoutExists and isPageExists

---
 .../core/lib/client/components/Content.js      |  2 +-
 .../lib/client/components/GlobalLayout.vue     |  2 +-
 .../core/lib/client/plugins/Store.d.ts         | 12 +++++-------
 .../core/lib/client/plugins/VuePress.d.ts      | 14 ++++----------
 .../core/lib/client/plugins/VuePress.js        | 18 ++++--------------
 packages/docs/docs/theme/option-api.md         |  2 +-
 packages/docs/docs/zh/theme/option-api.md      |  2 +-
 7 files changed, 17 insertions(+), 35 deletions(-)

diff --git a/packages/@vuepress/core/lib/client/components/Content.js b/packages/@vuepress/core/lib/client/components/Content.js
index b4811acf72..5e8bad5561 100644
--- a/packages/@vuepress/core/lib/client/components/Content.js
+++ b/packages/@vuepress/core/lib/client/components/Content.js
@@ -8,7 +8,7 @@ export default {
   },
   render (h) {
     const pageKey = this.pageKey || this.$parent.$page.key
-    if (this.$vuepress.isPageExists(pageKey)) {
+    if (this.$hasComponent(pageKey)) {
       return h(pageKey)
     }
     return h('')
diff --git a/packages/@vuepress/core/lib/client/components/GlobalLayout.vue b/packages/@vuepress/core/lib/client/components/GlobalLayout.vue
index e137bb3c0f..bfcf5511d4 100644
--- a/packages/@vuepress/core/lib/client/components/GlobalLayout.vue
+++ b/packages/@vuepress/core/lib/client/components/GlobalLayout.vue
@@ -7,7 +7,7 @@ export default {
   computed: {
     layout () {
       if (this.$page.path) {
-        if (this.$vuepress.isLayoutExists(this.$page.frontmatter.layout)) {
+        if (this.$hasComponent(this.$page.frontmatter.layout)) {
           return this.$page.frontmatter.layout
         }
         return 'Layout'
diff --git a/packages/@vuepress/core/lib/client/plugins/Store.d.ts b/packages/@vuepress/core/lib/client/plugins/Store.d.ts
index d290e852a7..007d0b6887 100644
--- a/packages/@vuepress/core/lib/client/plugins/Store.d.ts
+++ b/packages/@vuepress/core/lib/client/plugins/Store.d.ts
@@ -1,15 +1,13 @@
 import Vue from 'Vue'
 
 export declare class Store {
-  store: Vue;
+  store: Vue
 
-  $get(key: string): any;
+  $get(key: string): any
 
-  $set(key: string, value: any): void;
+  $set(key: string, value: any): void
 
-  $emit: typeof Vue.prototype.$emit;
+  $emit: typeof Vue.prototype.$emit
 
-  $on: typeof Vue.prototype.$on;
+  $on: typeof Vue.prototype.$on
 }
-
-
diff --git a/packages/@vuepress/core/lib/client/plugins/VuePress.d.ts b/packages/@vuepress/core/lib/client/plugins/VuePress.d.ts
index 48af0be18c..3d6eba736c 100644
--- a/packages/@vuepress/core/lib/client/plugins/VuePress.d.ts
+++ b/packages/@vuepress/core/lib/client/plugins/VuePress.d.ts
@@ -1,14 +1,8 @@
-import { Store } from './Store';
-import { AsyncComponent } from 'vue'
+import { Store } from './Store'
 
-declare class VuePress extends Store {
-  isPageExists (pageKey: string): boolean;
-
-  isLayoutExists (pageKey: string): boolean;
-}
-
-declare module "vue/types/vue" {
+declare module 'vue/types/vue' {
   export interface Vue {
-    $vuepress: VuePress;
+    $vuepress: Store
+    $hasComponent (key: string): boolean
   }
 }
diff --git a/packages/@vuepress/core/lib/client/plugins/VuePress.js b/packages/@vuepress/core/lib/client/plugins/VuePress.js
index c5043b3138..afa90fa9be 100644
--- a/packages/@vuepress/core/lib/client/plugins/VuePress.js
+++ b/packages/@vuepress/core/lib/client/plugins/VuePress.js
@@ -1,4 +1,3 @@
-import Vue from 'vue'
 import Store from './Store'
 
 // TODO: reuse this function in shared-utils
@@ -14,20 +13,11 @@ function cached (fn) {
 
 const pascalize = cached((str = '') => str.replace(/(^|-)\w/g, s => s.slice(-1).toUpperCase()))
 
-class VuePress extends Store {
-  isPageExists (pageKey) {
-    return Boolean(Vue.component(pascalize(pageKey)))
-  }
-
-  isLayoutExists (layout) {
-    return Boolean(Vue.component(pascalize(layout)))
-  }
-}
-
 export default {
   install (Vue) {
-    const ins = new VuePress()
-    Vue.$vuepress = ins
-    Vue.prototype.$vuepress = ins
+    const vuepress = new Store()
+    Vue.$vuepress = vuepress
+    Vue.prototype.$vuepress = vuepress
+    Vue.prototype.$hasComponent = key => Boolean(Vue.component(pascalize(key)))
   }
 }
diff --git a/packages/docs/docs/theme/option-api.md b/packages/docs/docs/theme/option-api.md
index 57ac02cd9c..0f8d7b0a25 100755
--- a/packages/docs/docs/theme/option-api.md
+++ b/packages/docs/docs/theme/option-api.md
@@ -111,7 +111,7 @@ export default {
   computed: {
     layout () {
       if (this.$page.path) {
-        if (this.$vuepress.isLayoutExists(this.$frontmatter.layout)) {
+        if (this.$hasComponent(this.$frontmatter.layout)) {
           return this.$frontmatter.layout
         }
         return 'Layout'
diff --git a/packages/docs/docs/zh/theme/option-api.md b/packages/docs/docs/zh/theme/option-api.md
index 3fb8ccd359..3a665eff34 100755
--- a/packages/docs/docs/zh/theme/option-api.md
+++ b/packages/docs/docs/zh/theme/option-api.md
@@ -111,7 +111,7 @@ export default {
   computed: {
     layout () {
       if (this.$page.path) {
-        if (this.$vuepress.isLayoutExists(this.$frontmatter.layout)) {
+        if (this.$hasComponent(this.$frontmatter.layout)) {
           return this.$frontmatter.layout
         }
         return 'Layout'