wip: more consistent compiler-sfc usage + inline mode for ssr

packages/runtime-core/src/component.ts

@@ -223,6 +223,11 @@ export interface ComponentInternalInstance {
    * @internal
    */
   render: InternalRenderFunction | null
+  /**
+   * SSR render function
+   * @internal
+   */
+  ssrRender?: Function | null
   /**
    * Object containing values this component provides for its descendents
    * @internal
@@ -610,7 +615,13 @@ export function handleSetupResult(
 ) {
   if (isFunction(setupResult)) {
     // setup returned an inline render function
-    instance.render = setupResult as InternalRenderFunction
+    if (!__BROWSER__ && (instance.type as ComponentOptions).__ssrInlineRender) {
+      // when the function's name is `ssrRender` (compiled by SFC inline mode),
+      // set it as ssrRender instead.
+      instance.ssrRender = setupResult
+    } else {
+      instance.render = setupResult as InternalRenderFunction
+    }
   } else if (isObject(setupResult)) {
     if (__DEV__ && isVNode(setupResult)) {
       warn(

packages/runtime-core/src/componentOptions.ts

@@ -121,7 +121,6 @@ export interface ComponentOptionsBase<
   /**
    * SSR only. This is produced by compiler-ssr and attached in compiler-sfc
    * not user facing, so the typing is lax and for test only.
-   *
    * @internal
    */
   ssrRender?: (
@@ -136,6 +135,13 @@ export interface ComponentOptionsBase<
     $options: ComponentInternalInstance['ctx']
   ) => void
 
+  /**
+   * Only generated by compiler-sfc to mark a ssr render function inlined and
+   * returned from setup()
+   * @internal
+   */
+  __ssrInlineRender?: boolean
+
   /**
    * marker for AsyncComponentWrapper
    * @internal