git-status -- trying to understand all possible states

I also have this question posted to stack overflow ( http://stackoverflow.com/questions/22792906/how-do-i-produce-every-possible-git-status ), but perhaps this is a better place to ask this question.

In working on some code which provides an interface to existing git repositories the question I had was "what actions should I present to a user", which lead to the question, "what does a user need to do to generate that condition", which lead to developing this gist:

https://gist.github.com/the-michael-toy/9907309

... which is a ruby script which tries to produce a repository with a file in every possible "git-status" XY condition

Of the 24 possibilities (not counting ignored) in git-status, there are 7 that I can't figure out how to generate.

D M deleted from index C [ MD] copied in index D D unmerged, both deleted A U unmerged, added by us U A unmerged, added by them

any clues, including pointers to "just go read XXX" would be appreciated.