introduce a default render implementation on the base widget, which add_media and then call the newly introduced method _render(form, field, formrenderer), abstract of the base widget class. This allow a litle code factorisation and avoid to forget the call to add_media in subclasses.

from cubicweb.devtools.testlib import CubicWebTC
from cubicweb.web import uicfg

class UICFGTC(CubicWebTC):

    def test(self):
        self.skip('write some tests')

if __name__ == '__main__':
    from logilab.common.testlib import unittest_main
    unittest_main()