https://svn.apache.org/repos/asf/subversion/trunk/contrib/client-side/svnmerge/svnmerge.py
contains this function:
def is_wc(dir):
"""Check if a directory is a working copy."""
return os.path.isdir(os.path.join(dir, ".svn")) or \
os.path.isdir(os.path.join(dir, "_svn"))
which needs to be updated somehow for 1.7 working copies. (Making it
unconditionally return True seems to be a semi-adequate workaround.)
