feat(runtime): 允许挂载东西在小程序 app 全局对象上

packages/taro-runtime/src/dsl/instance.ts

@@ -76,4 +76,6 @@ export interface AppInstance extends Show {
   onLaunch? (options?: string): void
   mount? (component: React.ComponentClass | ComponentOptions<VueCtor> | Vue3Component, id: string, cb: () => void): void
   unmount? (id: string, cb: () => void): void
+  onPageNotFound? (res: any): void
+  optionsExtraKeys?: string[]
 }

packages/taro-runtime/src/dsl/react.ts

@@ -230,6 +230,25 @@ export function createReactApp (App: React.ComponentClass, react: typeof React,
         // eslint-disable-next-line react/no-render-return-value
         wrapper = ReactDOM.render(R.createElement(AppWrapper), document.getElementById('app'))
         const app = ref.current
+
+        // For taroize
+        // 把 App Class 上挂载的额外属性同步到全局 app 对象中
+        if (app?.optionsExtraKeys?.length) {
+          app.optionsExtraKeys.forEach(key => {
+            Object.defineProperty(this, key, {
+              configurable: true,
+              enumerable: true,
+              get () {
+                return app[key]
+              },
+              set (value) {
+                app[key] = value
+              }
+            })
+          })
+        }
+        this.$app = app
+
         if (app != null && isFunction(app.onLaunch)) {
           app.onLaunch(options)
         }