Description:
git-annex can no longer copy files to webdav backends (e.g., Box).

This problem appeared with the upgrade to git-annex 6.20170925-1 and the simultaneous update to haskell-dav 1.3.1-158.

With this upgrade, when attempting to copy a file to box, I get the following error:

DAV failure: Status {statusCode = 405, statusMessage = "Method Not Allowed"} "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n<d:error xmlns:d=\"DAV:\" xmlns:s=\"http://sabredav.org/ns\">\n <s:exception>Sabre_DAV_Exception_MethodNotAllowed</s:exception>\n <s:message>The resource you tried to create already exists</s:message>\n</d:error>\n"
CallStack (from HasCallStack):
error, called at ./Remote/WebDAV.hs:381:78 in main:Remote.WebDAV
failed
git-annex: copy: 1 failed

This is *not* an upstream bug. I reported this bug upstream to discover that it is not an upstream problem. The most upstream standalone build (6.20170929-gffc127582) works fine. See the bug report and conversation here:

https://git-annex.branchable.com/bugs/git-annex_can_no_longer_copy_files_to_box/

Additional info:
* package version(s)

git-annex 6.20170925-1
haskell-dav 1.3.1-158

* config and/or log files etc.

The webdav backed was originally set up with

WEBDAV_USERNAME=[username] WEBDAV_PASSWORD=[passwd] git annex initremote box type=webdav url=https://dav.box.com/dav/git-annex chunk=100mb keyid=[keyid]

Steps to reproduce:

Set up a webdav remote per the command above. Then with in the git annex repository add and copy a file to webdav.

git-annex add test.pdf
git-annex copy -t box test.pdf