Link to index page with getServerSideProps and basePath results in full page reload

Bug report

Describe the bug

Using the experimental basePath and linking from any page back to the index page with Link results in a full page reload if the index page uses getServerSideProps. Looking at the network tab in Chrome I see a request to http://localhost:3000/base/_next/data/development.json that 404s. In the production build, the request that 404s looks like this http://localhost:3000/base/_next/data/xpCmLw_g1hPw_3b847mWF.json. I believe there’s a / missing before .json.

To Reproduce

1. Clone this repo https://github.com/bernardop/next-basepath-repro
2. Install dependencies and yarn dev
3. Go to http://localhost:3000/base
4. Click on “a” or “b”
5. Click on “Back” link
6. Index page does a full load and the network tab shows 404 to .json

Expected behavior

Index page should not fully reload.

System information

• OS: macOS
• All browsers
• Version of Next.js: 9.4.5-canary.8
• Version of Node.js: 14.4.0

Additional context

I believe this was introduced in 9.4.5-canary.8 and I suspect #13876 is the culprit. 9.4.5-canary.7 does not have this error.

[ijjk]

Closing as this is resolved on latest canary, please reply with additional details if you are still encountering problems after upgrading

[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.