"svn switch" is able to switch a file to a directory but, having done that,
cannot switch the directory back to the file. When "d" is a directory and "f"
is a file, the output is:
+ svn switch file:///home/julianfoad/tmp/svn-switch-test/repos/d f
D f
A f
Updated to revision 1.
+ svn switch file:///home/julianfoad/tmp/svn-switch-test/repos/f f
/home/julianfoad/src/subversion/subversion/libsvn_repos/delta.c:209:
(apr_err=160005)
svn: Invalid filesystem path syntax
svn: svn_repos_dir_delta: invalid editor anchoring; at least one of the input
paths is not a directory and there was no source entry