Undefined value in router query now become undefined string

[lephuongbg]

Version

3.4.0

Reproduction link

https://jsfiddle.net/herophuong/97bq4vmh/

Steps to reproduce

1. Call $router.push({path: '/', query: {q: undefined}})

What is expected?

URL should be /

What is actually happening?

URL is now /?q=undefined

---

Possibly due to fixing this issue: #2131

[pfdgithub]

This problem is introduced from 3.0.3
https://github.com/vuejs/vue-router/releases/tag/v3.0.3

undefined should be ignored

[posva]

FYI this has been fixed and released. Undefined query Params are removed from the string representation