Increase unit tests / code coverage

[khufkens]

R6 implementation shifted things about needs more unit tests to cover functions.

• wf_transfer()
• ...

[eliocamp]

wf_transfer() needs to be better adapted to the new implementation, I think. Ideally, it could only be url$transfer() since all the work is donde in the class. However, right now it has a lot of code to cover the case of url being a.. you know, an URL 🤣. Is this needed?

If it is, then I think it should change a bit. Instead of doing all that work, it should just create a new request object with the hardcoded URL (no request$submit() needed) and then call request$transfer().

[khufkens]

I think that we should keep the wf_transer() function even if it isn't used anymore. People might use it in their custom workflows and it can be kept, if not just as a wrapper for request$transfer(). But yes, for consistency a formal request$transfer() would probably be consistent with the new scheme.

[khufkens]

Bumped things up (69%), but gui related calls and error trapping which can't be triggered (e.g. servers offline etc) pull coverage down. Most important parts are now tested though.

[khufkens]

FYI. Think things are now set for release 1.4!