docs: plugin-vue-jsx

packages/plugin-vue-jsx/README.md

@@ -1,14 +1,56 @@
 # @vitejs/plugin-vue-jsx
 
-Provides optimized Vue 3 JSX support via [@vue/babel-plugin-jsx](https://github.com/vuejs/jsx-next).
+Provides Vue 3 JSX & TSX support with HMR.
 
 ```js
 // vite.config.js
 import vueJsx from '@vitejs/plugin-vue-jsx'
 
 export default {
-  plugins: [vueJsx({
-    // options are passed on to @vue/babel-plugin-jsx
-  })]
+  plugins: [
+    vueJsx({
+      // options are passed on to @vue/babel-plugin-jsx
+    })
+  ]
 }
 ```
+
+## Options
+
+See [@vue/babel-plugin-jsx](https://github.com/vuejs/jsx-next).
+## HMR Detection
+
+This plugin supports HMR of Vue JSX components. The detection requirements are:
+
+- The component must be exported.
+- The component must be declared by calling `defineComponent` via a root-level statement, either variable declaration or export declaration.
+
+### Supported patterns
+
+```jsx
+import { defineComponent } from 'vue'
+
+// named exports w/ variable declaration: ok
+export const Foo = defineComponent(...)
+
+// named exports referencing vairable declaration: ok
+const Bar = defineComponent(...)
+export { Bar }
+
+// default export call: ok
+export default defineComponent(...)
+
+// default export referencing variable declaration: ok
+const Baz = defineComponent(...)
+export default Baz
+```
+
+### Non-supported patterns
+
+```jsx
+// not using `defineComponent` call
+export const Bar = { ... }
+
+// not exported
+const Foo = defineComponent(...)
+```