Description of problem:


Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1.  Create RepoA and sync some rpms to it
2.  Create RepoB, and unit copy some rpms from RepoA (DO NOT PUBLISH RepoB)
3.  Create RepoC
3.  Attempt to unit_copy one or more rpms from RepoB to RepoC  with dependency solving enabled.
  
Actual results:
Error in pulp.log when task is executed:     

raise Errors.NoMoreMirrorsRepoError, errstr


Expected results:

Some more meaningful error indicating that RepoB (the source repo) needs to be published before pulp can dependency solve

Additional info:

Ideally this check would happen before the unit_copy is attempted, so the task doesn't get started and I have to check its status.