Sparse-checkout fails to delete junction points when deleted out of order

[derrickstolee]

• I was not able to find an open or closed issue matching what I'm seeing

Setup

• Which version of Git for Windows are you using? Is it 32-bit or 64-bit?

I'm using the microsoft/git fork, but I don't expect the problem to be in the code that is custom to that fork.

$ git version --build-options
git version 2.46.0.vfs.0.0
cpu: x86_64
built from commit: 081a80eda51c258b0a2a3b9fc786143d03edc926
sizeof-long: 4
sizeof-size_t: 8
shell-path: D:/git-sdk-64-build-installers/usr/bin/sh
feature: fsmonitor--daemon
libcurl: 8.9.0
OpenSSL: OpenSSL 3.2.2 4 Jun 2024
zlib: 1.3.1

• Which version of Windows are you running? Vista, 7, 8, 10? Is it 32-bit or 64-bit?

$ cmd.exe /c ver

Microsoft Windows [Version 10.0.26120.1542]

• What options did you set as part of the installation? Or did you choose the
  defaults?

$ cat /etc/install-options.txt
Editor Option: VIM
Custom Editor Path:
Default Branch Option: main
Path Option: Cmd
SSH Option: OpenSSH
Tortoise Option: false
CURL Option: WinSSL
CRLF Option: CRLFAlways
Bash Terminal Option: MinTTY
Git Pull Behavior Option: Rebase
Use Credential Manager: Enabled
Performance Tweaks FSCache: Enabled
Enable Symlinks: Enabled
Enable Pseudo Console Support: Disabled
Enable FSMonitor: Disabled

Details

• Which terminal/shell are you running Git from? e.g Bash/CMD/PowerShell/other

Issue happens in Git Bash or CMD (though my setup requires CMD)

• What commands did you run to trigger this issue? If you can provide a
  Minimal, Complete, and Verifiable example
  this will help us understand the issue.

(in bash)
git init junction-test
cd junction-test
echo "**/ignored/" >.gitignore
mkdir dir1
mkdir dir2
echo bogus >a
echo bogus >dir1/a
echo bogus >dir2/a
git add .
git commit -m "base"
mkdir -p dir1/ignored/target
mkdir dir2/ignored

(now, in CMD)
mklink /J dir2\ignored\source dir2\ignored\target

(now, in any shell)
git sparse-checkout set

• What did you expect to occur after running these commands?

git sparse-checkout set should have no error output and the only file in the working dir should be a. (In a more general case, the directories that live outside of the sparse-checkout should not exist.)

• What actually happened instead?

$ git sparse-checkout set
warning: could not open directory 'dir2/ignored/source/': No such file or directory
warning: failed to remove directory 'dir2/'

$ ls
a        dir2/

Context Notes

This example is contrived, but matches the behavior of an internal monorepo that uses junction points between shared contents of node_modules directories to save space when building Javascript components. This behavior is causing performance issues with the sparse index as alerted by the new advice message in Git 2.46.0.