keep-alive deeply nested router-views display the last visited component component

[lxcuso4]

Version

3.1.3

Reproduction link

https://jsfiddle.net/lxcuso4/cu6keqw2/28

Steps to reproduce

Click on childA
Click on index
Click on childB

What is expected?

we want to show B page

What is actually happening?

but actually A page dispaly

---

This behavior happens when we use keep-alive and have three layers of nested routing

[posva]

Similar to #2552 if anybody wants to try fixing this

[songpeng0501]

I tested that the following code works in src/component/view.js

    var matched = route.matched[depth];
  // render empty node if no matched route
  if (!matched) {
    cache[name] = null;
    return h()
  }
  // render previous view if the tree is inactive and kept-alive
  if (inactive && (cache[name] === matched.components[name])) {
    return h(cache[name], data, children)
  }

you are right