Router query empty in componentDidMount

Bug report

Describe the bug

The docs state: The query object will be empty during prerendering if the page is statically optimized. but I am also seeing the query object empty in the componentDidMount lifecycle method.

To Reproduce

1. Clone https://github.com/zlwaterfield/next-router-query-test
2. Run yarn dev
3. Go to http://localhost:3004/router-test?test=test
4. Notice the query object is empty but the document.location.search is correct and the query shows in asPath.

Expected behavior

The query object should be

{
  test: 'test'
}

Screenshots

System information

• Version of Next.js: 9.4.0

Additional context

I understand the query object would be empty in the prerender but should it not show when the component is mounted?

[zlwaterfield]

Ah, I found this:

Pages that are statically optimized by Automatic Static Optimization will be hydrated without their route parameters provided, i.e query will be an empty object ({}).

After hydration, Next.js will trigger an update to your application to provide the route parameters in the query object.

I will confirm this and then look into making a PR to make it more clear in the docs. Thanks for the help.

[balazsorban44]

This issue has been automatically locked due to no recent activity. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.