git diff-files weirdness (bug?)

Hi,

I was investigating a bug in "stg refresh" failing with moved files and noticed that it was caused by Git (HEAD pulled yesterday):

  git init
  touch a
  git add a
  git commit -m "test"
  git mv a b

These are OK:

  git diff-files -- a
  git diff-files -- b

These fail:

  git diff-files -- a b
  git diff-files -- a c

These are OK:

  git diff-files -- a b c
  git diff-files -- a b c d e
  git diff-files -- c d e
  ...

It looks like the two arguments command is a special case. Passing "-q" doesn't make any difference.

Thanks.