[PATCH] Fix callbacks argument for svn.ra.open2() in Python bindings

Hi,

The attached patch makes the SWIG bindings throw an exception whenever a
svn_ra_callbacks2_t() argument is NULL and allows the user to pass in a
Python object for callbacks (none of the functions on this object are
called yet).

Is calling svn_swig_py_svn_exception() directly like I do in
svn_swig_py_setup_ra_callbacks correct?

Changes:

[[[
 * subversion/bindings/swig/python/libsvn_swig_py/swigutil_py.c: Add
svn_swig_py_setup_ra_callbacks helper function

 * subversion/bindings/swig/python/libsvn_swig_py/swigutil_py.h:
Prototype for svn_swig_py_setup_ra_callbacks

 * subversion/bindings/swig/python/tests/ra.py: Do not pass None
   for callbacks argument to svn.ra.open2()

 * subversion/bindings/swig/svn_ra.i: Forbid passing NULL for
svn_ra_callbacks2_t arguments, add Python typemap for
svn_ra_callbacks2_t

]]]

Cheers,

Jelmer

-- 
Jelmer Vernooij <jelmer_at_samba.org> - http://samba.org/~jelmer/