Doesn't work well with relative path across drivers on Windows

Input:

D:\a\pnp-rs\pnp-rs\fixtures\global-cache\../../../../../../C:/Users/runneradmin/AppData/Local/Yarn/Berry/cache/source-map-npm-0.6.1-1a3621db16-10c0.zip/node_modules/source-map/

Expected:

C:\Users\runneradmin\AppData\Local\Yarn\Berry\cache\source-map-npm-0.6.1-1a3621db16-10c0.zip\node_modules\source-map\

Actually:

C:Users\runneradmin\AppData\Local\Yarn\Berry\cache\source-map-npm-0.6.1-1a3621db16-10c0.zip\node_modules\source-map\

The \ is mssing after C: