perf: mark defineComponent as side-effects-free (#8512)

Author: antfu

package.json

@@ -87,7 +87,7 @@
     "prettier": "^2.7.1",
     "pug": "^3.0.1",
     "puppeteer": "~19.6.0",
-    "rollup": "^3.20.2",
+    "rollup": "^3.26.0",
     "rollup-plugin-dts": "^5.3.0",
     "rollup-plugin-esbuild": "^5.0.0",
     "rollup-plugin-polyfill-node": "^0.12.0",

packages/runtime-core/src/apiAsyncComponent.ts

@@ -40,6 +40,7 @@ export interface AsyncComponentOptions<T = any> {
 export const isAsyncWrapper = (i: ComponentInternalInstance | VNode): boolean =>
   !!(i.type as ComponentOptions).__asyncLoader
 
+/*! #__NO_SIDE_EFFECTS__ */
 export function defineAsyncComponent<
   T extends Component = { new (): ComponentPublicInstance }
 >(source: AsyncComponentLoader<T> | AsyncComponentOptions<T>): T {

packages/runtime-core/src/apiDefineComponent.ts

@@ -274,6 +274,7 @@ export function defineComponent<
 >
 
 // implementation, close to no-op
+/*! #__NO_SIDE_EFFECTS__ */
 export function defineComponent(
   options: unknown,
   extraOptions?: ComponentOptions

packages/runtime-dom/src/apiCustomElement.ts

@@ -140,6 +140,7 @@ export function defineCustomElement(options: {
   new (...args: any[]): ComponentPublicInstance
 }): VueElementConstructor
 
+/*! #__NO_SIDE_EFFECTS__ */
 export function defineCustomElement(
   options: any,
   hydrate?: RootHydrateFunction
@@ -155,6 +156,7 @@ export function defineCustomElement(
   return VueCustomElement
 }
 
+/*! #__NO_SIDE_EFFECTS__ */
 export const defineSSRCustomElement = ((options: any) => {
   // @ts-ignore
   return defineCustomElement(options, hydrate)