The image can have no repository in case it has not been published.
Soo...technically correct. But you could have 2+ levels of intermediate images. Not sure if we have them in practice. But I would almost guarantee we do...
That's good point, I will rework it to pass list of children.
rebased onto 4a22bc15b7c46ecdafc2b33a1a0ace284f279ee9
Updated.
+1
Pull-Request has been merged by jkaluza
The image can have no repository in case it has not been published.