Issues with git branch checkout due to untracked working tree files

I thought I put the days of Xcode + git issues behind me. Guess not. I am getting this git error when trying to checkout another branch.

error: The following untracked working tree files would be overwritten by checkout:
    RCAlpha.xcodeproj/project.xcworkspace/xcuserdata/andrewjl.xcuserdatad/UserInterfaceState.xcuserstate
    RCAlpha.xcodeproj/xcuserdata/andrewjl.xcuserdatad/xcschemes/RCAlpha.xcscheme
    RCAlpha.xcodeproj/xcuserdata/andrewjl.xcuserdatad/xcschemes/xcschememanagement.plist
Please move or remove them before you can switch branches.
Aborting

Very well I say, let me remove these files:

andrewjl$ git rm --cached RCAlpha.xcodeproj/project.xcworkspace/xcuserdata/andrewjl.xcuserdatad/UserInterfaceState.xcuserstate
fatal: pathspec 'RCAlpha.xcodeproj/project.xcworkspace/xcuserdata/andrewjl.xcuserdatad/UserInterfaceState.xcuserstate' did not match any files

At this point I'm not sure what to do. These files are all listed in my .gitignore and I also gave git clean -f -d a try as well. No dice. Anyone know what's going on here?

Solution

The files are untracked: git rm --cached cannot find them because there are not in the index. Just delete them, using your file manager or rm. Then checkout should work as expected. Note that git status will show you what git sees the files as (tracked, changed, untracked; with an additional option it will also display ignored files).