The documentation also says "Be careful, if the directory contains symlinks, the function will follow them.", which is dangerous and inappropriate but thankfully not actually what removeDirectoryRecursive does (based on testing and also on reading the code).  That statement should be removed from the documentation.

I'm indifferent on whether the argument path itself should be able to be a symlink to a directory, and if so, whether the target directory and/or the symlink should be removed, and whether this should differ based on whether the path ends in a "/" or not.  (Many Unix operations on symlinks, like `ls`, do differ based on a trailing slash. `rm -rf symlink` removes just the symlink; `rm -rf symlink/` appears to remove the contents of the target directory but neither the symlink nor the target directory itself...)

-Isaac

On 06/10/2014 09:42 AM, Gracjan Polak wrote:

Hi all,

A crime scene:

Prelude System.Directory> :!mkdir a-directory
Prelude System.Directory> :!touch a-directory/a-file.txt
Prelude System.Directory> :!ln -s "a-directory" "a-symlink-to-a-directory"
Prelude System.Directory> :!ls a-directory
a-file.txt
Prelude System.Directory> :!ls a-symlink-to-a-directory
a-file.txt
Prelude System.Directory> removeDirectoryRecursive
                              "a-symlink-to-a-directory"
*** Exception: a-symlink-to-a-directory: removeDirectory:
     inappropriate type (Not a directory)
Prelude System.Directory> :!ls a-symlink-to-a-directory
Prelude System.Directory> :!ls a-directory
Prelude System.Directory> :!ls -a a-directory
.       ..
Prelude System.Directory> :!ls -a a-symlink-to-a-directory
.       ..
Prelude System.Directory>

removeDirectoryRecursive is removing all contents *of the directory linked*
but is unable to remove the symlink itself.

This behavior is surprizing if not dangerous. I understand that this mimics
behavior of unlink/rmdir and DeleteFile/RemoveDirectory. but let me quote
relevant manuals:

man rm:
The rm utility removes symbolic links, not the files referenced by the links.

DeleteFile docs:
If the path points to a symbolic link, the symbolic link is deleted, not the
target. To delete a target, you must call CreateFile and specify
FILE_FLAG_DELETE_ON_CLOSE.

RemoveDirectory removes a directory junction, even if the contents of the
target are not empty; the function removes directory junctions regardless of
the state of the target object.

Note: doesDirectoryExist and doesFileExist follow symlinks so they add more
surprize to the scenario.

What can we do about this?

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