1.6 working copies inside of 1.7 ones.

Ah, Realization. How you come to me, sledgehammer in hand.

amalia:~ $ cd ~/tests/ ### a 1.7 working copy directory
amalia:~/tests $ svn st -v
              2213 2072 cmpilato .
amalia:~/tests $ mkdir -p A/B/C/D/E/F/G
amalia:~/tests $ cd A/B/C/D/E/F/G
amalia:~/tests/A/B/C/D/E/F/G $
~/projects/subversion/branches/1.6.x/subversion/svn/svn co --depth empty
http://svn.apache.org/repos/asf
subversion/libsvn_wc/questions.c:79: (apr_err=155021)
svn: The path 'asf' appears to be part of a Subversion 1.7 or greater
working copy rooted at '/home/cmpilato/tests'.
Please upgrade your Subversion client to use this working copy.

I would assume this to mean that if you have a computer with, say, the root
directory under version control with Subversion 1.7, you can pretty much
never use Subversion 1.6 on that machine.

I would also assume that, since my ~/projects/subversion directory is a 1.7
working copy, I would be unable to run the 1.6 test suite from
~/projects/subversion/branches/1.6.x. But I don't see similar problems when
I try that. Whyzat? Anybody know?

-- 
C. Michael Pilato <cmpilato@red-bean.com> | http://cmpilato.blogspot.com/