The '--dotfiles' option does not work as expected in conjunction with tree folding

[MalbrottsAsnan]

Hello,

The behaviour of the '--dotfiles' option seems unexpected when stow folds subtrees containing 'dot-' prefixed files. It appears that tree folding takes precedence over '--dotfiles', which is unintuitive as we are explicitly requesting translation to a dotfile.

Steps to reproduce:
$ tree -a ~
/home/user/
...
└── stow
 └── stow-dir
  └── pkg-dir
   └── dot-file

$ cd ~/stow && stow --dotfiles stow-dir

Expected behaviour:
$ tree -a ~
/home/user/
...
├── pkg-dir
│ └── .file -> ../stow/stow-dir/pkg-dir/dot-file
└── stow
 └── stow-dir
  └── pkg-dir
   └── dot-file

Actual behaviour:
$ tree -a ~
/home/user/
...
├── pkg-dir -> stow/stow-dir/pkg-dir
└── stow
 └── stow-dir
  └── pkg-dir
   └── dot-file

Would it be possible to modify the implementation of '--dotfiles' or introduce an option to control this behaviour? While a workaround is to use '--no-folding', it is not ideal since you lose a lot of functionality. Another workaround is to manually create the 'pkg-dir' prior to stowing, which would then also result in the expected behaviour shown above.

Additionally, if this new behaviour is to be implemented, I'm assuming it would be impossible/out of scope to have 'pkg-dir' removed when unstowing with 'stow -D stow-dir'. This means that stow will leave empty directories after itself even when it "owns" everything, which I understand may not align with design guidelines. Should it be implemented however, a note in the '--dotfiles' documentation warning about this would likely also be needed.

[aspiers]

Hi, thanks for the report. Please can you confirm which version you see this on?

[MalbrottsAsnan]

Of course, I also forgot to mention that I'm using WSL2. I'm not sure if/how this affects stow, so if there's a user error on my part, feel free to let me know! I have tested on Debian and Ubuntu and the behavior is identical even though '--verbose' output is different between the stow versions.

On Debian in WSL2:

$ stow -V
stow (GNU Stow) version 2.4.1

$ perl -v
This is perl 5, version 36, subversion 0 (v5.36.0) built for x86_64-linux-gnu-thread-multi
...

$ hostnamectl
...
Virtualization: wsl
Operating System: Debian GNU/Linux 12 (bookworm)
Kernel: Linux 5.15.167.4-microsoft-standard-WSL2
Architecture: x86-64

On Ubuntu in WSL2:

$ stow -V
stow (GNU Stow) version 2.3.1

$ perl -v
This is perl 5, version 38, subversion 2 (v5.38.2) built for x86_64-linux-gnu-thread-multi
...

$ hostnamectl
...
Virtualization: wsl
Operating System: Ubuntu 24.04.1 LTS
Kernel: Linux 5.15.167.4-microsoft-standard-WSL2
Architecture: x86-64

Verbose outputs

--verbose=5 on Debian in WSL2:

$ stow --dotfiles --simulate --verbose=5 stow-dir
stow dir is /home/user/stow
stow dir path relative to target /home/user is stow
Planning stow of: stow-dir ...
cwd now /home/user
     | Joining: stow stow-dir
     | Final join: stow/stow-dir
Planning stow of package stow-dir...
     | Joining: . .stow
     | Final join: .stow
     | Joining: . .nonstow
     | Final join: .nonstow
 . not protected; shouldn't skip
Stowing contents of stow / stow-dir / . (cwd=/home/user)
 target subdir is .
     | Joining: stow stow-dir .
     | Final join: stow/stow-dir
    | Checking whether . is a current/planned node
    | link_task_action(.): no task
    | dir_task_action(.): no task
     | Joining: .
     | Final join: .
    | parent_link_scheduled_for_removal(.): prefix .
    | parent_link_scheduled_for_removal(.): returning false
   | is_a_node(.): really exists
     | Joining: . pkg-dir
     | Final join: pkg-dir
     | Joining: . pkg-dir
     | Final join: pkg-dir
     | Joining: stow stow-dir
     | Final join: stow/stow-dir
     | Joining: stow/stow-dir .stow-local-ignore
     | Final join: stow/stow-dir/.stow-local-ignore
     | Joining: /home/user .stow-global-ignore
     | Final join: /home/user/.stow-global-ignore
 stow/stow-dir/.stow-local-ignore didn't exist
 /home/user/.stow-global-ignore didn't exist
 Using built-in ignore list
  Ignore list regexp for paths: /(?^:(^|/)(^/.stow-local-ignore$|^/LICENSE.|^/COPYING|^/README.)(/|$))/
  Ignore list regexp for segments: /(?^:^(CVS|.cvsignore|.svn|.+,v|.#.+|_darcs|#.*#|.gitmodules|.git|.+~|.gitignore|RCS|.hg)$)/
 Not ignoring pkg-dir
Stowing entry stow / stow-dir / pkg-dir
     | Joining: stow stow-dir pkg-dir
     | Final join: stow/stow-dir/pkg-dir
 level of pkg-dir is 0
     | Joining: stow/stow-dir/pkg-dir
     | Final join: stow/stow-dir/pkg-dir
 link destination stow/stow-dir/pkg-dir
  is_a_link(pkg-dir)
    | link_task_action(pkg-dir): no task
  is_a_link(pkg-dir): returning 0
    | Checking whether pkg-dir is a current/planned node
    | link_task_action(pkg-dir): no task
    | dir_task_action(pkg-dir): no task
     | Joining: pkg-dir
     | Final join: pkg-dir
    | parent_link_scheduled_for_removal(pkg-dir): prefix pkg-dir
    | parent_link_scheduled_for_removal(pkg-dir): returning false
   | is_a_node(pkg-dir): returning false
LINK: pkg-dir => stow/stow-dir/pkg-dir
Planning stow of package stow-dir... done
cwd restored to /home/user/stow
WARNING: in simulation mode so not modifying filesystem.

--verbose=5 on Ubuntu in WSL2:

$ stow --dotfiles --simulate --verbose=5 stow-dir
stow dir is /home/user/stow
stow dir path relative to target /home/user is stow
cwd now /home/user
cwd restored to /home/user/stow
cwd now /home/user
Planning stow of package stow-dir...
. not protected
Stowing contents of stow/stow-dir (cwd=/home/user)
=> stow/stow-dir
is_a_node(.)
link_task_action(.): no task
dir_task_action(.): no task
parent_link_scheduled_for_removal(.): prefix
parent_link_scheduled_for_removal(.): returning false
is_a_node(.): really exists
stow/stow-dir/.stow-local-ignore didn't exist
/home/user/.stow-global-ignore didn't exist
Using built-in ignore list
Ignore list regexp for paths: /(?^:(^|/)(^/COPYING|^/README.|^/.stow-local-ignore$|^/LICENSE.)(/|$))/
Ignore list regexp for segments: /(?^:^(.+,v|.hg|.gitignore|CVS|.#.+|.git|.cvsignore|RCS|_darcs|.+~|.svn|#.*#)$)/
Not ignoring pkg-dir
Adjusting: pkg-dir => pkg-dir
Stowing stow / stow-dir / pkg-dir
=> stow/stow-dir/pkg-dir
is_a_link(pkg-dir)
link_task_action(pkg-dir): no task
is_a_link(pkg-dir): returning 0
is_a_node(pkg-dir)
link_task_action(pkg-dir): no task
dir_task_action(pkg-dir): no task
parent_link_scheduled_for_removal(pkg-dir): prefix pkg-dir
parent_link_scheduled_for_removal(pkg-dir): returning false
is_a_node(pkg-dir): returning false
LINK: pkg-dir => stow/stow-dir/pkg-dir
Planning stow of package stow-dir... done
cwd restored to /home/user/stow
WARNING: in simulation mode so not modifying filesystem.

[aspiers]

Much appreciated, especially with all the very helpful and well-structured detail. While anything prior to 2.4.0 can be flakey with respect to --dotfiles, it sounds like you have discovered a genuine bug here still present in 2.4.1. Hopefully it won't be too hard to figure out and fix given the work I did in 2.4.0 to clean up that code, but I won't know until I take a closer look.

[MalbrottsAsnan]

Thank you for your quick response and for looking into it!