Okay, this seems to fail, tests never end - I canceled them. Not sure if we need to replace the undefined case or it should be that way.

Oh yea. I was wondering today which issue/pr was that and what was it about ;d

Linking #545 and #415 to have it more near to my stuff.

Also, it probably is fixed too, because it checks against !part.mime to detect whether it's a file or field.

We should add some option to control it through option