Clone from a datalad-annex WebDAV URL pointing to a directory that doesn't exist will create that directory

[mslw]

I am starting with a dataset that was published to my Sciebo account (using create-sibling-webdav) under $BASEURL/test-20230524/CamelCaseDirectory" (where base URL is the webdav url shown in Sciebo UI).

First, I am cloning the dataset to a new location, without any issues:

$ datalad clone "datalad-annex::?type=webdav&encryption=none&exporttree=no&url=$BASEURL/test-20230524/CamelCaseDirectory" clone_camel_case
[INFO   ] Remote origin uses a protocol not supported by git-annex; setting annex-ignore                                                      
[INFO   ] access to 1 dataset sibling sciebo-storage not auto-enabled, enable with:
    (...)
install(ok): /home/mszczepanik/Documents/test/lettercase/clone_camel_case (dataset)

Unexpected behavior occurs when using a bogus url (pointing to a directory that doesn't exist in Sciebo). Clone ends with OK and a warning, "You appear to have cloned an empty repository". The cloned dataset is a git repo with no commits.

$ datalad clone "datalad-annex::?type=webdav&encryption=none&exporttree=no&url=$BASEURL/test-20230524/nonexistentdirectory" clone_non_existent
[WARNING] You appear to have cloned an empty repository.                                                                                      
[WARNING] Cloned /home/mszczepanik/Documents/test-taylan/lettercase/clone_non_existent but could not find a branch with commits               
install(ok): /home/mszczepanik/Documents/test/lettercase/clone_non_existent (dataset)

The URLs are case-sensitive, the same happens when typing the url with (incorrect) lowercase:

$ datalad clone "datalad-annex::?type=webdav&encryption=none&exporttree=no&url=$BASEURL/test-20230524/camelcasedirectory" clone_wrong_case
[WARNING] You appear to have cloned an empty repository.                                                                                      
[WARNING] Cloned /home/mszczepanik/Documents/test/lettercase/clone_wrong_case but could not find a branch with commits                 
install(ok): /home/mszczepanik/Documents/test/lettercase/clone_wrong_case (dataset)

And in the end my Sciebo folder contains CamelCaseDirectory (correctly created with create-sibling-webdav), but also nonexistentdirectory and camelcasedirectory which came into being during clone attempts.

Is this an issue with server behavior or with DataLad behavior?

[mih]

Is the issue that empty directories remain at the locations that you provided as arguments?

If that is true, under which conditions would you like to see them removed? For Git it is perfectly fine to clone an empty repository. Here datalad-annex would need to reliably distinguish between a repo that exists and is empty, and a repo that does not exist. This would need to be done independent of the particular special remote used (i.e. whether or not this is webdav).

[mslw]

Is the issue that empty directories remain at the locations that you provided as arguments?

In Sciebo. My main issue is that when given a sciebo path that would fall under my account but does not exist (not an empty folder, just no such directory), clone creates a new folder (in sciebo -- sciebo url / nonexistentdirectory in my example did not exist before cloning, but got created by clone).

That the local outcome is an empty repo is secondary, although the behaviour I'd expect would be an error like "repository not found", "could not read from remote repository", or similar - like ones that I get when trying to git clone from a GitHub repo (or a local folder) that does not exist.

FTR this came out when debugging a failed clone due to misspelled url (that's why I started with letter casing in examples).

But these may in fact be non-issues, maybe my expectations are wrong - you can be the judge here.