Rewrites bug

This source code reproduces a bug that occurs when the rewrites option is used with basePath and public directory. I can't rewrite to the desired URL. If any of the conditions are not met, the bug will not occur.

How to Reproduce

First, build next server and run it.

npm install
npm run build
npm run start

Second, GET the url what should be rewritten. http://localhost:3000/todos

Expected Result

$ curl -I 'http://localhost:3000/todos'
HTTP/1.1 200 OK
...

Actual Result

$ curl -I 'http://localhost:3000/todos'
HTTP/1.1 404 Not Found
Cache-Control: no-cache, no-store, max-age=0, must-revalidate
X-Powered-By: Next.js
ETag: "9b4-euJYEtH38aPbb6xrjZoe12UwZLA"
Content-Type: text/html; charset=utf-8
Content-Length: 2484
Vary: Accept-Encoding
Date: Wed, 19 Aug 2020 02:14:54 GMT
Connection: keep-alive