'Test parsing of an error element with a text with a defined language.'

def test_textLang(self):

    text = self.error.addElement(('errorns', 'text'))
    text[(NS_XML, 'lang')] = 'en_US'
    text.addContent(u'test')
    result = error._parseError(self.error, 'errorns')
    self.assertEqual('en_US', result['textLang'])
