spread operator in esm-bundler

[94mashiro]

Version

4.0.1

Reproduction link

https://cdn.bootcdn.net/ajax/libs/vue-router/4.0.1/vue-router.esm-bundler.js

Steps to reproduce

execute line 2395 made page crash

What is expected?

page not crash

What is actually happening?

page crash

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esm-bundle should not appear es6 syntax

[posva]

Nice catch! This one is easy to fix: it needs to use the assign function exported from utils. This is a good first contribution, no test needed