Is CreateAsFolder supposed to silently delete an existing folder?

As the title says… I have unzip code that is based on some example from MBS, which does a CreateAsFolder if the zipped item is a folder

Untouched for a long time, I am getting reports from some people that it actually throws away an existing folder which contains data.
I was under the impression that to delete a folder, we had to recursively delete the contents, but that doesnt seem to be the case.
The documentation is silent on this

Xojo 2017

Why not check folderitem.exists before creating?

[quote]
Why not check folderitem.exists before creating?[/quote]
I do now.
I havent needed to for a long time.
And didnt think I needed to, for the reasons above.

I want to know what the expected behaviour is, because a customer is angry with me, and I would like to know if I should be angry with myself or the docs.

I don’t expect that behavior and in a quick test here with 2018r4 on Windows 10 and High Sierra I am not seeing that CreateFolder is removing an existing folder that has content in it.

Well, the expected behavior is that this either does nothing (since the folder already exists) or shows an error.
A quick test on macOS 64Bit: folder (and it’s content) remain. And theFolderItem.LastErrorCode = 105 (invalid name)