update

The "props" and "emits" attributes have been merged when creating component instances, so there is no need to merge them here. It's OK to directly reference the previously merged values

packages/runtime-core/src/componentOptions.ts

@@ -969,6 +969,8 @@ export function resolveMergedOptions(
   if (isObject(base)) {
     cache.set(base, resolved)
   }
+  resolved.props = instance.propsOptions[0]
+  resolved.emits = instance.emits
   return resolved
 }
 
@@ -1000,6 +1002,8 @@ export function mergeOptions(
           `"expose" option is ignored when declared in mixins or extends. ` +
             `It should only be declared in the base component itself.`
         )
+    } else if (key === "props" || key === "emits") {
+      continue
     } else {
       const strat = internalOptionMergeStrats[key] || (strats && strats[key])
       to[key] = strat ? strat(to[key], from[key]) : from[key]
@@ -1010,8 +1014,6 @@ export function mergeOptions(
 
 export const internalOptionMergeStrats: Record<string, Function> = {
   data: mergeDataFn,
-  props: mergeObjectOptions, // TODO
-  emits: mergeObjectOptions, // TODO
   // objects
   methods: mergeObjectOptions,
   computed: mergeObjectOptions,